Background Nocardia brasiliensis  is a rare human pathogen usually associated with localized cutaneous infections.
Background
Nocardia brasiliensis  is a rare human pathogen usually associated with localized cutaneous infections.Nocardia brasiliensisCase Presentation We report a case of primary lymphocutaneous  Nocardia brasiliensis  infection developed after a bone fracture of the left hand of an otherwise healthy 32-year-old man. Treatment with trimethoprim-sulfamethoxazole given for a total of three months combined with surgical debridement resulted in complete resolution of the infection.
Case Presentation
We report a case of primary lymphocutaneous  Nocardia brasiliensis  infection developed after a bone fracture of the left hand of an otherwise healthy 32-year-old man. Treatment with trimethoprim-sulfamethoxazole given for a total of three months combined with surgical debridement resulted in complete resolution of the infection.Nocardia brasiliensisConclusion Nocardiosis should be part of the differential diagnosis in patients with sporotrichoid infection, particularly those with a history of outdoor injury. Culture of the affected tissue and antimicrobial susceptibility testing of the isolate should be performed for diagnosis and treatment.
Conclusion
Nocardiosis should be part of the differential diagnosis in patients with sporotrichoid infection, particularly those with a history of outdoor injury. Culture of the affected tissue and antimicrobial susceptibility testing of the isolate should be performed for diagnosis and treatment.

Background Nocardiosis is a rare localized or systemic infection caused by several species of the genus  Nocardia . This genus consists of strictly aerobic, Gram-positive, variably acid-fast, filamentous bacteria with a tendency to fragment into bacillary and coccoid forms [ 1 ].  N. asteroides ,  N. farcinica ,  N. nova  (included in the  N. asteroides  complex) and  N. brasiliensis  are the species most often involved in human disease [ 1 , 2 ].  N. brasiliensis  has been recovered from the soil in many tropical and subtropical areas but rarely in temperate areas. Traumatic inoculation of  N. brasiliensis  into the skin is the most typical mode of acquisition of the infection due to this organism [ 1 , 2 ]. Herein, we describe a case of a man, who had an accident at work and 1 week later developed lymphocutaneous infection caused by  N. brasiliensis .
Background
Nocardiosis is a rare localized or systemic infection caused by several species of the genus  Nocardia . This genus consists of strictly aerobic, Gram-positive, variably acid-fast, filamentous bacteria with a tendency to fragment into bacillary and coccoid forms [ 1 ].  N. asteroides ,  N. farcinica ,  N. nova  (included in the  N. asteroides  complex) and  N. brasiliensis  are the species most often involved in human disease [ 1 , 2 ].  N. brasiliensis  has been recovered from the soil in many tropical and subtropical areas but rarely in temperate areas. Traumatic inoculation of  N. brasiliensis  into the skin is the most typical mode of acquisition of the infection due to this organism [ 1 , 2 ].NocardiaN. asteroidesN. farcinicaN. novaN. asteroidesN. brasiliensisN. brasiliensisN. brasiliensisHerein, we describe a case of a man, who had an accident at work and 1 week later developed lymphocutaneous infection caused by  N. brasiliensis .N. brasiliensisCase Presentation A previously healthy 32-year-old man was referred to the emergency department of orthopedics with traumatic injuries of the index, middle and ring fingers of the left hand. The injury happened at work while he was operating a machine of cotton elaboration. On admission, routine laboratory investigations showed only elevated white blood cell count (12,400/mm 3 ), while red blood cell count, haemoglobin, chemistry and urine analysis were within normal limits. Radiography of the bones of his left hand revealed fractures of the nail bones of the middle and the ring finger. Surgical debridement of the damaged soft tissue was undertaken with amputation of these two nail bones. The patient was hospitalized and intravenous therapy with ceforanide (1 g/12 h), ofloxacin (200 mg/12 h) and metronidazole (500 mg/8 h) was initiated. Four days after his admission the injury of the hand became tender, erythematous, swelling and began to drain. The purulent material expressed from the hand was sent for culture. Three days later the lesion worsened and was complicated with lymphangitis. The patient was noted to be febrile (38.5°C) without any other systemic symptoms. Physical examination revealed multiple erythematous subcutaneous nodules along the lymphatics extending up the patient's left forearm. These nodules were tender and painful. There was no regional lymphadenopathy. Debridement of the lesions was performed and the tissue was submitted for bacterial and fungal cultures. The Gram-stained smear showed polymorphonuclear leucocytes and Gram-positive fine, branching filaments, partially acid-fast, with a tendency to fragment into coccoid and bacillary forms. Laboratory tests showed: white blood cell count (18,000/mm 3 ), absolute neutrophil count, 12,780/mm 3 , erythrocyte sedimentation rate, 75 mm/h; and C-reactive protein, 14.2 mg/dl (normal < 0.8 mg/dl). After 5 days of incubation cultures of the pus and the tissue on Columbia blood agar grew white colonies adherent to the agar, rough with a velvety surface, having a characteristic mouldy odor (Figure  1 ). Colonial characteristics, physiological properties and biochemical tests performed identified the isolate as  Nocardia brasiliensis  (Table  1 ). Susceptibility to the antibiotics by the determination of the MICs using the E-test method (AB Biodisk, Solna, Sweden), showed that the isolate was sensitive to trimethoprim-sulfamethoxazole, amoxicillin-clavulanic acid, gentamicin, tobramycin, amikacin, and minocycline, intermediate to ciprofloxacin and resistant to ampicillin, second and third generation cephalosporins, erythromycin, clindamycin, ofloxacin and pefloxacin. The patient's antimicrobial therapy was changed to intravenous trimethoprim-sulfamethoxazole (160/800 mg b.i.d). The patient responded to therapy. Following 2 weeks of treatment the patient improved and all laboratory tests returned to normal. He was discharged 3 weeks after his admission on oral trimethoprim-sulfamethoxazole (160/800 mg b.i.d). The antibiotic therapy was continued for a total of 3 months. His hand and arm lesions were healing well and 6 months later revealed complete resolution of the infection without signs of recurrence. Figure 1 Rough chalky-white colonies of  Nocardia brasiliensis  grown on Columbia blood agar Table 1 Physiological characteristics and biochemical reactions of our  Nocardia brasiliensis  isolate Test or characteristic Reaction of our strain Decomposition of: Adenine - Casein + Tyrosine + Xanthine - API 20C AUX assimilation results: Glucose + Glycerol + Galactose + N-acetyl-D-glucosamine + Inositol + Adonitol - Trehalose + Equivalent growth at 35°/45°C - Lysozyme broth + Production of arylsulfatase (7d) - Gelatin liquefaction (7d) + Sensitivity to: Gentamicin + Tobramycin + Amikacin + Erythromycin -
Case Presentation
A previously healthy 32-year-old man was referred to the emergency department of orthopedics with traumatic injuries of the index, middle and ring fingers of the left hand. The injury happened at work while he was operating a machine of cotton elaboration.On admission, routine laboratory investigations showed only elevated white blood cell count (12,400/mm 3 ), while red blood cell count, haemoglobin, chemistry and urine analysis were within normal limits. Radiography of the bones of his left hand revealed fractures of the nail bones of the middle and the ring finger. Surgical debridement of the damaged soft tissue was undertaken with amputation of these two nail bones. The patient was hospitalized and intravenous therapy with ceforanide (1 g/12 h), ofloxacin (200 mg/12 h) and metronidazole (500 mg/8 h) was initiated.Four days after his admission the injury of the hand became tender, erythematous, swelling and began to drain. The purulent material expressed from the hand was sent for culture. Three days later the lesion worsened and was complicated with lymphangitis. The patient was noted to be febrile (38.5°C) without any other systemic symptoms.Physical examination revealed multiple erythematous subcutaneous nodules along the lymphatics extending up the patient's left forearm. These nodules were tender and painful. There was no regional lymphadenopathy. Debridement of the lesions was performed and the tissue was submitted for bacterial and fungal cultures. The Gram-stained smear showed polymorphonuclear leucocytes and Gram-positive fine, branching filaments, partially acid-fast, with a tendency to fragment into coccoid and bacillary forms.Laboratory tests showed: white blood cell count (18,000/mm 3 ), absolute neutrophil count, 12,780/mm 3 , erythrocyte sedimentation rate, 75 mm/h; and C-reactive protein, 14.2 mg/dl (normal < 0.8 mg/dl).After 5 days of incubation cultures of the pus and the tissue on Columbia blood agar grew white colonies adherent to the agar, rough with a velvety surface, having a characteristic mouldy odor (Figure  1 ). Colonial characteristics, physiological properties and biochemical tests performed identified the isolate as  Nocardia brasiliensis  (Table  1 ). Susceptibility to the antibiotics by the determination of the MICs using the E-test method (AB Biodisk, Solna, Sweden), showed that the isolate was sensitive to trimethoprim-sulfamethoxazole, amoxicillin-clavulanic acid, gentamicin, tobramycin, amikacin, and minocycline, intermediate to ciprofloxacin and resistant to ampicillin, second and third generation cephalosporins, erythromycin, clindamycin, ofloxacin and pefloxacin. The patient's antimicrobial therapy was changed to intravenous trimethoprim-sulfamethoxazole (160/800 mg b.i.d). The patient responded to therapy. Following 2 weeks of treatment the patient improved and all laboratory tests returned to normal. He was discharged 3 weeks after his admission on oral trimethoprim-sulfamethoxazole (160/800 mg b.i.d). The antibiotic therapy was continued for a total of 3 months. His hand and arm lesions were healing well and 6 months later revealed complete resolution of the infection without signs of recurrence.Nocardia brasiliensisPhysiological characteristics and biochemical reactions of our  Nocardia brasiliensis  isolateNocardia brasiliensisTest or characteristicReaction of our strainDiscussion In the United States, there are an estimated 500–1,000 new cases of nocardiosis each year [ 3 ]. On the basis of epidemiological surveys conducted in France and Italy, the annual estimated incidence of human nocardiosis is 150–250 and 90–130 cases, respectively [ 4 , 5 ].  N. brasiliensis  accounts for only about 7–14% of the reported cases [ 3 ]. The incidence of nocardiosis in Greece is still unknown because the number of nocardial infections are not reported to the public health authorities. Only one case of  N. brasiliensis  lymphocutaneous syndrome has been previously described in the same geographic area [ 6 ]. N. brasiliensis  although rarely implicated in pulmonary and disseminated infections in immunocompromised patients, has been most commonly associated with cutaneous infections [ 7 ].  Nocardia  enters the skin after traumatic inoculation injuries, varying from contaminated abrasions and puncture wounds to insect and animal bites. The most common resulting skin lesions are on the upper and lower extremities [ 7 ]. Cutaneous manifestations include: (i) mycetoma, (ii) lymphocutaneous (sporotrichoid) infection, (iii) superficial skin infection, and (iv) disseminated infection with cutaneous involvement. The present case is consistent with the classical presentation of lymphocutaneous infection with a primary lesion at the site of injury on the hand and an ascending lymphangitis involving the forearm. The inoculation probably occurred from the cotton that had been contaminated by  Nocardia  and entered the wound after the accident. The lymphocutaneous syndrome can be caused by a wide variety of microorganisms. The most common causative agents of the syndrome in addition to  Sporothrix schenkii  and  Nocardia brasiliensis , include  Mycobacterium marinum  and  Leishmania  species. Less common causes are  Coccidioides immitis ,  Cryptococcus neoformans ,  Histoplasma capsulatum ,  Blastomyces dermatitidis ,  Pseudoallescheria boydii , other species of  Mycobacterium ,  Streptococcus pyogenes ,  Staphylococcus aureus  and viruses as cowpox virus and herpes simplex [ 8 ]. A history of a traumatic wound contaminated with soil and the relatively brief incubation period (less than 2 weeks) suggest nocardiosis. Diagnosis of nocardial infection can be established by cultural isolation of the microorganism. Identification to the species level can be successfully performed either by conventional biochemical methods or by molecular techniques [ 1 , 9 ]. Trimethoprim-sulfamethoxazole combination is recognized the drug of choice for nocardiosis [ 10 ]. Primary lymphocutaneous nocardiosis may be curable after a course of 2 to 4 months, although several studies report clinical cures of cutaneous nocardiosis caused by  N. brasiliensis  after only 2 to 3 weeks of therapy. In patients with sulfa intolerance or those who fail therapy with trimethoprim-sulfamethoxazole, alternative therapy must be based on sensitivity testing. Minocycline, tetracycline, amikacin and amoxicillin-clavulanic acid have been successfully used [ 11 ]. Although rare, lymphocutaneous nocardiosis must be considered, diagnosed with appropriate cultures and adequately treated, in order to prevent progression to dissemination of the primary skin disease.
Discussion
In the United States, there are an estimated 500–1,000 new cases of nocardiosis each year [ 3 ]. On the basis of epidemiological surveys conducted in France and Italy, the annual estimated incidence of human nocardiosis is 150–250 and 90–130 cases, respectively [ 4 , 5 ].  N. brasiliensis  accounts for only about 7–14% of the reported cases [ 3 ]. The incidence of nocardiosis in Greece is still unknown because the number of nocardial infections are not reported to the public health authorities. Only one case of  N. brasiliensis  lymphocutaneous syndrome has been previously described in the same geographic area [ 6 ].N. brasiliensisN. brasiliensisN. brasiliensis  although rarely implicated in pulmonary and disseminated infections in immunocompromised patients, has been most commonly associated with cutaneous infections [ 7 ].  Nocardia  enters the skin after traumatic inoculation injuries, varying from contaminated abrasions and puncture wounds to insect and animal bites. The most common resulting skin lesions are on the upper and lower extremities [ 7 ]. Cutaneous manifestations include: (i) mycetoma, (ii) lymphocutaneous (sporotrichoid) infection, (iii) superficial skin infection, and (iv) disseminated infection with cutaneous involvement.N. brasiliensisNocardiaThe present case is consistent with the classical presentation of lymphocutaneous infection with a primary lesion at the site of injury on the hand and an ascending lymphangitis involving the forearm. The inoculation probably occurred from the cotton that had been contaminated by  Nocardia  and entered the wound after the accident.NocardiaThe lymphocutaneous syndrome can be caused by a wide variety of microorganisms. The most common causative agents of the syndrome in addition to  Sporothrix schenkii  and  Nocardia brasiliensis , include  Mycobacterium marinum  and  Leishmania  species. Less common causes are  Coccidioides immitis ,  Cryptococcus neoformans ,  Histoplasma capsulatum ,  Blastomyces dermatitidis ,  Pseudoallescheria boydii , other species of  Mycobacterium ,  Streptococcus pyogenes ,  Staphylococcus aureus  and viruses as cowpox virus and herpes simplex [ 8 ]. A history of a traumatic wound contaminated with soil and the relatively brief incubation period (less than 2 weeks) suggest nocardiosis. Diagnosis of nocardial infection can be established by cultural isolation of the microorganism. Identification to the species level can be successfully performed either by conventional biochemical methods or by molecular techniques [ 1 , 9 ].Sporothrix schenkiiNocardia brasiliensisMycobacterium marinumLeishmaniaCoccidioides immitisCryptococcus neoformansHistoplasma capsulatumBlastomyces dermatitidisPseudoallescheria boydiiMycobacteriumStreptococcus pyogenesStaphylococcus aureusTrimethoprim-sulfamethoxazole combination is recognized the drug of choice for nocardiosis [ 10 ]. Primary lymphocutaneous nocardiosis may be curable after a course of 2 to 4 months, although several studies report clinical cures of cutaneous nocardiosis caused by  N. brasiliensis  after only 2 to 3 weeks of therapy. In patients with sulfa intolerance or those who fail therapy with trimethoprim-sulfamethoxazole, alternative therapy must be based on sensitivity testing. Minocycline, tetracycline, amikacin and amoxicillin-clavulanic acid have been successfully used [ 11 ].N. brasiliensisAlthough rare, lymphocutaneous nocardiosis must be considered, diagnosed with appropriate cultures and adequately treated, in order to prevent progression to dissemination of the primary skin disease.


Background The rates of Sexually transmitted diseases (STDs) in England have been rising steadily since the mid 1990s, making them a major public health concern. In 2003, 672,718 people were diagnosed with an STD in England, and around one third of those cases were diagnosed in London.
Background
The rates of Sexually transmitted diseases (STDs) in England have been rising steadily since the mid 1990s, making them a major public health concern. In 2003, 672,718 people were diagnosed with an STD in England, and around one third of those cases were diagnosed in London.Results Using GeoReveal v1.1 for Windows, we produced Web-based interactive choropleth maps of diagnoses of STDs by Primary Care Trust (PCT) in London for the years from 1997 to 2003  . These maps are in Scalable Vector Graphics (SVG) format and require a freely available Adobe SVG browser plug-in to be displayed. They are based on data obtained from the House of Commons Hansard Written Answers for 15 October 2004. They show steadily rising rates of STDs in London over the covered seven-year period. Also, one can clearly see on the maps that PCTs located in central London had the highest numbers of STD diagnoses throughout the mapped seven years. A companion bar chart allows users to instantly compare the STD figure of a given PCT for a given year against the average figure for all 25 mapped PCTs for the same year, and also compare those figures across all seven years. The maps offer users a rich set of useful features and functions, including the ability to change the classification method in use, the number of ranges in the map, and the colour theme, among others.
Results
Using GeoReveal v1.1 for Windows, we produced Web-based interactive choropleth maps of diagnoses of STDs by Primary Care Trust (PCT) in London for the years from 1997 to 2003  . These maps are in Scalable Vector Graphics (SVG) format and require a freely available Adobe SVG browser plug-in to be displayed. They are based on data obtained from the House of Commons Hansard Written Answers for 15 October 2004. They show steadily rising rates of STDs in London over the covered seven-year period. Also, one can clearly see on the maps that PCTs located in central London had the highest numbers of STD diagnoses throughout the mapped seven years. A companion bar chart allows users to instantly compare the STD figure of a given PCT for a given year against the average figure for all 25 mapped PCTs for the same year, and also compare those figures across all seven years. The maps offer users a rich set of useful features and functions, including the ability to change the classification method in use, the number of ranges in the map, and the colour theme, among others.Conclusions Wizard-driven tools like GeoReveal have made it very easy to transform complex raw data into valuable decision support information products (interactive Web maps) in very little time and without requiring much expertise. The resultant interactive maps have the potential of further supporting health planners and decision makers in their planning and management tasks by allowing them to graphically interrogate data, instantly spot trends, and make quick and effective visual comparisons of geographically differentiated phenomena between different geographical areas and over time. SVG makes an ideal format for such maps. SVG is a World Wide Web Consortium non-proprietary, XML-based vector graphics format, and is an extremely powerful alternative to Macromedia ®  Flash and bitmap graphics.
Conclusions
Wizard-driven tools like GeoReveal have made it very easy to transform complex raw data into valuable decision support information products (interactive Web maps) in very little time and without requiring much expertise. The resultant interactive maps have the potential of further supporting health planners and decision makers in their planning and management tasks by allowing them to graphically interrogate data, instantly spot trends, and make quick and effective visual comparisons of geographically differentiated phenomena between different geographical areas and over time.SVG makes an ideal format for such maps. SVG is a World Wide Web Consortium non-proprietary, XML-based vector graphics format, and is an extremely powerful alternative to Macromedia ®  Flash and bitmap graphics.

Background Sexually transmitted diseases (STDs) have become a major public health concern in the UK during recent years. The rates of STDs in England have been rising steadily since the mid 1990s. In 2003, the number of STDs in England rose by 4% compared to 2002. Overall, 672,718 people were diagnosed with an STD in England in 2003, and around one third of those cases were diagnosed in the London area alone [ 1 , 2 ]. The House of Commons Hansard Written Answers for 15 October 2004 included an answer by Melanie Johnson MP, Minister for Public Health at the Department of Health, to a question by Sarah Teather MP on "how many cases of diagnosed STDs there were in each Primary Care Trust (PCT) in London in each year since 1997". The answer was provided in the form of a long table showing the figures for 25 PCTs in London (Table  1  – [ 2 ]). Table 1 Diagnoses of STDs by PCT in London, 1997 – 2003 PCT Name 1997 1998 1999 2000 2001 2002 2003 Barking and Dagenham 2,454 2,797 3,020 2,764 2,457 3,461 3,292 Barnet 1,542 1,591 1,546 1,993 2,001 1,899 923 Brent 8,753 8,851 8,724 9,258 9,479 10,156 10,113 Bromley 1,386 1,899 2,287 2,468 3,296 3,683 3,575 Camden 15,714 17,117 17,478 18,750 20,962 22,257 26,987 City and Hackney 14,998 16,595 16,601 16,169 19,171 22,673 21,072 Croydon 4,089 5,546 5,707 6,968 7,805 7,995 7,587 Ealing 1,514 585 1,518 1,687 2,062 2,751 1,832 Enfield 581 1,513 1,168 1,481 1,957 2,129 1,659 Greenwich 4,361 4,314 4,901 6,012 5,170 5,385 6,607 Hammersmith and Fulham 7,838 7,889 8,281 9,556 9,992 4,996 5,723 Haringey 5,029 5,229 5,568 6,344 7,183 6,617 6,379 Hillingdon 1,931 2,387 3,038 3,096 4,131 4,000 3,110 Hounslow 3,270 3,185 3,029 4,101 4,637 5,861 6,473 Islington 5,339 5,552 6,259 5,781 5,309 4,988 6,186 Kensington and Chelsea 11,995 11,636 11,040 13,149 13,301 11,739 12,243 Kingston 1,926 2,443 2,646 3,129 3,474 3,872 4,481 Lambeth 17,865 19,998 21,327 19,971 19,754 22,003 22,209 Lewisham 412 353 346 482 21 - - Newham 8,948 9,033 11,214 11,023 12,769 13,200 15,236 Southwark 16,481 17,073 15,232 13,836 16,699 19,618 19,249 Sutton and Merton 10,870 9,110 11,569 13,464 14,229 16,589 17,784 Walthamstow, Leyton and Leytonstone 1,157 1,355 1,726 1,713 2,311 2,433 2,988 Wandsworth 2,629 2,712 3,072 3,004 3,519 4,151 4,199 Westminster 18,639 21,490 21,359 20,503 20,870 18,462 19,657 Diagnoses of sexually transmitted diseases by Primary Care Trust in London, 1997 – 2003 (Source: [2]). Overall figures may be lower than stated for the London region in the annual report because the data presented here have not been imputed. One clinic in each of these PCTs (Barnet; City and Hackney) did not submit all the KC60 returns for 2003. The Alexis Clinic of Lewisham PCT closed in June 2001; no GUM clinics currently open in this PCT. Though the table presents all the requested data, it remains very difficult for the reader to fully appreciate the patterns and trends buried in them, or make quick and effective comparisons between the figures for different PCTs or between the seven data sets for the years from 1997 to 2003. Such data patterns, trends and comparisons derived from this Hansard table and other sources, e.g., demographic, deprivation/social exclusion, transport and existing GUM (Genito-Urinary Medicine) clinic data sets, are crucial for the decision maker wanting, for example, to: - improve access to GUM clinics and make decisions regarding the expansion or closure of existing clinics, or the creation of new ones; - channel resources and target STD prevention programmes to areas with the most need, or scale such programmes according to the magnitude of the problem in different areas (this is especially important in a climate of finite resources); and/or - monitor the impact of such programmes in a given area over time. In this paper, we describe a much better way of presenting the same Hansard table data in the form of interactive Web maps in Scalable Vector Graphics (SVG) format to further support health planners and decision makers in their planning and management tasks.
Background
Sexually transmitted diseases (STDs) have become a major public health concern in the UK during recent years. The rates of STDs in England have been rising steadily since the mid 1990s. In 2003, the number of STDs in England rose by 4% compared to 2002. Overall, 672,718 people were diagnosed with an STD in England in 2003, and around one third of those cases were diagnosed in the London area alone [ 1 , 2 ].The House of Commons Hansard Written Answers for 15 October 2004 included an answer by Melanie Johnson MP, Minister for Public Health at the Department of Health, to a question by Sarah Teather MP on "how many cases of diagnosed STDs there were in each Primary Care Trust (PCT) in London in each year since 1997". The answer was provided in the form of a long table showing the figures for 25 PCTs in London (Table  1  – [ 2 ]).Diagnoses of STDs by PCT in London, 1997 – 2003PCT Name1997199819992000200120022003Diagnoses of sexually transmitted diseases by Primary Care Trust in London, 1997 – 2003 (Source: [2]). Overall figures may be lower than stated for the London region in the annual report because the data presented here have not been imputed. One clinic in each of these PCTs (Barnet; City and Hackney) did not submit all the KC60 returns for 2003. The Alexis Clinic of Lewisham PCT closed in June 2001; no GUM clinics currently open in this PCT.Though the table presents all the requested data, it remains very difficult for the reader to fully appreciate the patterns and trends buried in them, or make quick and effective comparisons between the figures for different PCTs or between the seven data sets for the years from 1997 to 2003.Such data patterns, trends and comparisons derived from this Hansard table and other sources, e.g., demographic, deprivation/social exclusion, transport and existing GUM (Genito-Urinary Medicine) clinic data sets, are crucial for the decision maker wanting, for example, to:- improve access to GUM clinics and make decisions regarding the expansion or closure of existing clinics, or the creation of new ones;- channel resources and target STD prevention programmes to areas with the most need, or scale such programmes according to the magnitude of the problem in different areas (this is especially important in a climate of finite resources); and/or- monitor the impact of such programmes in a given area over time.In this paper, we describe a much better way of presenting the same Hansard table data in the form of interactive Web maps in Scalable Vector Graphics (SVG) format to further support health planners and decision makers in their planning and management tasks.Results Using GeoReveal, a tool from Graphical Data Capture Ltd (  – see 'Methods' section below), we produced Web-based interactive choropleth maps of diagnoses of STDs by PCT in London for the years from 1997 to 2003, which readers can browse at   (Figure  1 ). These maps and companion bar chart ('Chart Panel') are based on the data in Table  1 , and show steadily rising rates of STDs in London over the covered seven-year period. Also, one can clearly see on the maps that PCTs located in central London, e.g., Camden PCT and Lambeth PCT, had the highest numbers of STD diagnoses throughout the seven years from 1997 to 2003. Figure 1 Screenshot from our interactive Web maps of STD diagnoses by London PCT, 1997 – 2003.  Screenshot from our Web-based interactive choropleth maps of diagnoses of STDs by PCT in London for the years from 1997 to 2003  . The map shown in this screenshot is for the year 2002, with Camden PCT highlighted in yellow. The bar chart ('Chart Panel') on the left shows steadily rising STD rates in Camden PCT over the covered seven-year period. Camden's rates are well above the average for all 25 mapped PCTs over the same period (the purple portions of the bars represent the average for all PCTs). The maps require the free Adobe SVG Viewer  . Visitors will be automatically prompted to download it on their first visit to the site, if they don't already have it installed on their machine. Scripting must also be enabled in Internet Explorer. As the mouse cursor is moved around the main map window, the 'Chart Panel' changes to display statistical data about the currently highlighted PCT. Each row of the bar chart represents data for one year and has two bars; a red bar that shows the value for the highlighted PCT, and a transparent blue bar which shows a mean value of this piece of data (or year) for all 25 mapped PCTs (when both bars overlap, a purple colour is produced – Figure  1 ). Additionally, clicking a PCT area on the map will display an information box with all available data for that PCT (Figure  2 ). Figure 2 Screenshots of two information boxes from our interactive Web map interface.  Upper information box: clicking a PCT area on the map ('Camden PCT' for this screenshot) will display this pop-up box with all available data for that PCT. Lower information box: clicking the 'Info' button (shown in Figure 1 – bottom right 'Navigation Panel') will open this pop-up box with extra information about the maps, links to the Web sites of London PCTs, and detailed help about the map interface. An 'Options Panel' controls the data that are shown in the map window. Users can tick the 'Background Map' box to add a raster background map of London to the main map. They can use the 'Choose Classification Method' list to select how the data are mapped; with equal ranges, equal counts or by highlighting the highest values. A 'Number of Colours' list allows users to select how many classes or ranges are used in the choropleth map (two to five ranges). Using the 'Select Map Topic' list, users can select the topic that is shown on the main map (a year from 1997 to 2003). Finally, users can select from the 'Colour of Theme' list the colour theme that is used in the main map (orange, green, or blue). Map zooming, panning, MapTips (displaying PCT names), and a dynamic legend are available. An overview map shows a miniature version of the full extent map. When the user zooms in, a rectangle on the overview map highlights the area that is currently being displayed in the main map window. The user can click and drag this rectangle to change the view in the main map window. After zooming into the main map, users can use the 'Reset' button to return to the full extent of the main map. An 'Info' button is also available. Clicking this button will open a pop-up window with extra information about the maps, links to the Web sites of London PCTs, and detailed help about the map interface (Figure  2 ).
Results
Using GeoReveal, a tool from Graphical Data Capture Ltd (  – see 'Methods' section below), we produced Web-based interactive choropleth maps of diagnoses of STDs by PCT in London for the years from 1997 to 2003, which readers can browse at   (Figure  1 ). These maps and companion bar chart ('Chart Panel') are based on the data in Table  1 , and show steadily rising rates of STDs in London over the covered seven-year period. Also, one can clearly see on the maps that PCTs located in central London, e.g., Camden PCT and Lambeth PCT, had the highest numbers of STD diagnoses throughout the seven years from 1997 to 2003.As the mouse cursor is moved around the main map window, the 'Chart Panel' changes to display statistical data about the currently highlighted PCT. Each row of the bar chart represents data for one year and has two bars; a red bar that shows the value for the highlighted PCT, and a transparent blue bar which shows a mean value of this piece of data (or year) for all 25 mapped PCTs (when both bars overlap, a purple colour is produced – Figure  1 ).Additionally, clicking a PCT area on the map will display an information box with all available data for that PCT (Figure  2 ).An 'Options Panel' controls the data that are shown in the map window. Users can tick the 'Background Map' box to add a raster background map of London to the main map. They can use the 'Choose Classification Method' list to select how the data are mapped; with equal ranges, equal counts or by highlighting the highest values. A 'Number of Colours' list allows users to select how many classes or ranges are used in the choropleth map (two to five ranges). Using the 'Select Map Topic' list, users can select the topic that is shown on the main map (a year from 1997 to 2003). Finally, users can select from the 'Colour of Theme' list the colour theme that is used in the main map (orange, green, or blue).Map zooming, panning, MapTips (displaying PCT names), and a dynamic legend are available. An overview map shows a miniature version of the full extent map. When the user zooms in, a rectangle on the overview map highlights the area that is currently being displayed in the main map window. The user can click and drag this rectangle to change the view in the main map window. After zooming into the main map, users can use the 'Reset' button to return to the full extent of the main map.An 'Info' button is also available. Clicking this button will open a pop-up window with extra information about the maps, links to the Web sites of London PCTs, and detailed help about the map interface (Figure  2 ).Discussion From complex raw data to valuable decision support information Turning raw tabular data into much more useful and accessible visual information in the form of interactive Web maps is much needed to support and empower decision makers, and even members of the general public. Such maps help us understand the relationships, patterns and trends buried in the original data sets and also enable instant visual comparisons to be made between different geographical areas and over time (when data sets for successive periods of time are available) [ 3 ]. We believe this transformation of raw data into valuable decision support information is very evident in the London STD example described in this paper. Readers only have to compare the original Hansard table (Table  1 ) with the corresponding interactive Web maps we have produced   to see the difference for themselves and appreciate the value of interactive maps. SVG: an ideal format for interactive Web maps SVG is a non-proprietary language for describing rich, stylable two-dimensional graphics and graphical applications in XML (eXtensible Markup Language). SVG is fully endorsed by the W3C (World Wide Web Consortium –  ). It is rapidly becoming a popular choice for delivering interactive Web maps, being designed to work effectively across platforms, output resolutions, colour spaces, and a range of available bandwidths. It offers a rich modern graphics format providing the ability for better map display, and advanced graphical features such as transparency, arbitrary geometry, filter effects (shadows, lighting effects, etc.), scripting, and animation [ 4 ]. All these features have made SVG a direct competitor to the proprietary Macromedia ®  Flash format [ 5 ]. Vector-based images (describing shapes and paths), such as those in SVG and SWF (Macromedia ®  Shockwave/Flash File) formats, will keep their sharp character when enlarged, while raster-based images (storing information about each and every pixel in the image), such as those saved in GIF (Graphics Interchange Format) or JPEG (Joint Photographic Experts Group) formats, will show jagged edges. A free SVG Web browser plug-in is available from Adobe for different platforms (Adobe SVG Viewer –  ), in the same way the free Adobe Reader software is available for rendering PDF (Portable Document Format) files. Besides the example described in this paper, other examples of SVG interactive Web maps in the health arena include the Office for National Statistics' England and Wales 2001 Census Key Statistics maps   and 2001 Area Classification for Health Areas maps  , and Leeds Interactive Health Atlas  . Tools for producing interactive SVG and Flash maps from desktop GIS projects Besides GeoReveal  , the tool we have used to produce the maps described in this paper (see 'Methods' section below), other SVG/Flash mapping tools available today for publishing maps created in desktop GIS (Geographic Information Systems) include GéoClip  , SVGMapMaker  , MapViewSVG  , and SVGMapper  . The latter two tools (MapViewSVG and SVGMapper) are specific to ESRI ArcView GIS. Table  2  provides an overview of the features of GeoReveal, GéoClip, and SVGMapMaker. Table 2 Overview of the features of GeoReveal, GéoClip, and SVGMapMaker GeoReveal GéoClip SVGMapMaker GeoReveal is a powerful .NET application that combines geography and statistics to produce revealing interactive graphics for the Web. It produces fully interactive geo-statistical presentations. There is no requirement for a GIS. GeoReveal uses MID/MIF files that can be exported from practically any GIS. Other information: - Unlimited data fields and includes a comprehensive set of pre-defined templates - Features a simple wizard driven interface and an advanced set of menus for users who need to fine tune the finished output - Generates SVG data, overlay boundaries, overview and background maps. For UK Local Government users, SVG is also an e-GIF (e-Goverment Interoperability Framework) compliant format - Presentations can include interactive charts that change to display statistics about the currently selected map region or area - Map display can be changed after generation, i.e., ability to change map topic, map colour, number of ranges, and classification method - Includes pre-prepared UK census boundary data and sample projects GéoClip is a MapBasic program that takes TAB file information and turns it into interactive Macromedia ®  Flash presentations. There is also a version for ESRI ArcGIS. GéoClip does not currently have an SVG component. Other information: - Written in MapBasic and therefore dependent on having a MapInfo Pro licence - Does not offer a very intuitive interface - Limited to ten data fields and to only one page layout - Users cannot remove the GéoClip logo/branding from the map page - Can only produce Flash (proprietary format, not e-GIF compliant) and not SVG (open format) - Some of its unique features like adjustable ranges and multiple themes are planned for the next release of GeoReveal SVGMapMaker is a MapBasic program that takes TAB file information and uses it to replicate limited GIS functionality in a browser window. It cannot be considered as a geo-statistical tool, as the level of interactivity is limited. For example, there are no interactive charts as provided in GeoReveal. Other information: - Written in MapBasic and therefore dependent on having a MapInfo Pro licence - Limited interface – no ability to change map topic and no statistical delivery - Map display cannot be changed after generation, i.e., no ability to change map colour, number of ranges, and classification method A quick comparison of three tools available today for producing interactive SVG and Flash maps from desktop GIS projects: GeoReveal (from Graphical Data Capture Ltd, London, UK –  ), GéoClip (from eMc3, a young company based in Toulouse, France –  ), and SVGMapMaker (from TETRAD Computer Applications Inc, Bellingham, WA, USA –  ).
Discussion
From complex raw data to valuable decision support information Turning raw tabular data into much more useful and accessible visual information in the form of interactive Web maps is much needed to support and empower decision makers, and even members of the general public. Such maps help us understand the relationships, patterns and trends buried in the original data sets and also enable instant visual comparisons to be made between different geographical areas and over time (when data sets for successive periods of time are available) [ 3 ]. We believe this transformation of raw data into valuable decision support information is very evident in the London STD example described in this paper. Readers only have to compare the original Hansard table (Table  1 ) with the corresponding interactive Web maps we have produced   to see the difference for themselves and appreciate the value of interactive maps.
From complex raw data to valuable decision support information
Turning raw tabular data into much more useful and accessible visual information in the form of interactive Web maps is much needed to support and empower decision makers, and even members of the general public. Such maps help us understand the relationships, patterns and trends buried in the original data sets and also enable instant visual comparisons to be made between different geographical areas and over time (when data sets for successive periods of time are available) [ 3 ].We believe this transformation of raw data into valuable decision support information is very evident in the London STD example described in this paper. Readers only have to compare the original Hansard table (Table  1 ) with the corresponding interactive Web maps we have produced   to see the difference for themselves and appreciate the value of interactive maps.SVG: an ideal format for interactive Web maps SVG is a non-proprietary language for describing rich, stylable two-dimensional graphics and graphical applications in XML (eXtensible Markup Language). SVG is fully endorsed by the W3C (World Wide Web Consortium –  ). It is rapidly becoming a popular choice for delivering interactive Web maps, being designed to work effectively across platforms, output resolutions, colour spaces, and a range of available bandwidths. It offers a rich modern graphics format providing the ability for better map display, and advanced graphical features such as transparency, arbitrary geometry, filter effects (shadows, lighting effects, etc.), scripting, and animation [ 4 ]. All these features have made SVG a direct competitor to the proprietary Macromedia ®  Flash format [ 5 ]. Vector-based images (describing shapes and paths), such as those in SVG and SWF (Macromedia ®  Shockwave/Flash File) formats, will keep their sharp character when enlarged, while raster-based images (storing information about each and every pixel in the image), such as those saved in GIF (Graphics Interchange Format) or JPEG (Joint Photographic Experts Group) formats, will show jagged edges. A free SVG Web browser plug-in is available from Adobe for different platforms (Adobe SVG Viewer –  ), in the same way the free Adobe Reader software is available for rendering PDF (Portable Document Format) files. Besides the example described in this paper, other examples of SVG interactive Web maps in the health arena include the Office for National Statistics' England and Wales 2001 Census Key Statistics maps   and 2001 Area Classification for Health Areas maps  , and Leeds Interactive Health Atlas  .
SVG: an ideal format for interactive Web maps
SVG is a non-proprietary language for describing rich, stylable two-dimensional graphics and graphical applications in XML (eXtensible Markup Language). SVG is fully endorsed by the W3C (World Wide Web Consortium –  ). It is rapidly becoming a popular choice for delivering interactive Web maps, being designed to work effectively across platforms, output resolutions, colour spaces, and a range of available bandwidths. It offers a rich modern graphics format providing the ability for better map display, and advanced graphical features such as transparency, arbitrary geometry, filter effects (shadows, lighting effects, etc.), scripting, and animation [ 4 ].All these features have made SVG a direct competitor to the proprietary Macromedia ®  Flash format [ 5 ]. Vector-based images (describing shapes and paths), such as those in SVG and SWF (Macromedia ®  Shockwave/Flash File) formats, will keep their sharp character when enlarged, while raster-based images (storing information about each and every pixel in the image), such as those saved in GIF (Graphics Interchange Format) or JPEG (Joint Photographic Experts Group) formats, will show jagged edges.A free SVG Web browser plug-in is available from Adobe for different platforms (Adobe SVG Viewer –  ), in the same way the free Adobe Reader software is available for rendering PDF (Portable Document Format) files.Besides the example described in this paper, other examples of SVG interactive Web maps in the health arena include the Office for National Statistics' England and Wales 2001 Census Key Statistics maps   and 2001 Area Classification for Health Areas maps  , and Leeds Interactive Health Atlas  .Tools for producing interactive SVG and Flash maps from desktop GIS projects Besides GeoReveal  , the tool we have used to produce the maps described in this paper (see 'Methods' section below), other SVG/Flash mapping tools available today for publishing maps created in desktop GIS (Geographic Information Systems) include GéoClip  , SVGMapMaker  , MapViewSVG  , and SVGMapper  . The latter two tools (MapViewSVG and SVGMapper) are specific to ESRI ArcView GIS. Table  2  provides an overview of the features of GeoReveal, GéoClip, and SVGMapMaker. Table 2 Overview of the features of GeoReveal, GéoClip, and SVGMapMaker GeoReveal GéoClip SVGMapMaker GeoReveal is a powerful .NET application that combines geography and statistics to produce revealing interactive graphics for the Web. It produces fully interactive geo-statistical presentations. There is no requirement for a GIS. GeoReveal uses MID/MIF files that can be exported from practically any GIS. Other information: - Unlimited data fields and includes a comprehensive set of pre-defined templates - Features a simple wizard driven interface and an advanced set of menus for users who need to fine tune the finished output - Generates SVG data, overlay boundaries, overview and background maps. For UK Local Government users, SVG is also an e-GIF (e-Goverment Interoperability Framework) compliant format - Presentations can include interactive charts that change to display statistics about the currently selected map region or area - Map display can be changed after generation, i.e., ability to change map topic, map colour, number of ranges, and classification method - Includes pre-prepared UK census boundary data and sample projects GéoClip is a MapBasic program that takes TAB file information and turns it into interactive Macromedia ®  Flash presentations. There is also a version for ESRI ArcGIS. GéoClip does not currently have an SVG component. Other information: - Written in MapBasic and therefore dependent on having a MapInfo Pro licence - Does not offer a very intuitive interface - Limited to ten data fields and to only one page layout - Users cannot remove the GéoClip logo/branding from the map page - Can only produce Flash (proprietary format, not e-GIF compliant) and not SVG (open format) - Some of its unique features like adjustable ranges and multiple themes are planned for the next release of GeoReveal SVGMapMaker is a MapBasic program that takes TAB file information and uses it to replicate limited GIS functionality in a browser window. It cannot be considered as a geo-statistical tool, as the level of interactivity is limited. For example, there are no interactive charts as provided in GeoReveal. Other information: - Written in MapBasic and therefore dependent on having a MapInfo Pro licence - Limited interface – no ability to change map topic and no statistical delivery - Map display cannot be changed after generation, i.e., no ability to change map colour, number of ranges, and classification method A quick comparison of three tools available today for producing interactive SVG and Flash maps from desktop GIS projects: GeoReveal (from Graphical Data Capture Ltd, London, UK –  ), GéoClip (from eMc3, a young company based in Toulouse, France –  ), and SVGMapMaker (from TETRAD Computer Applications Inc, Bellingham, WA, USA –  ).
Tools for producing interactive SVG and Flash maps from desktop GIS projects
Besides GeoReveal  , the tool we have used to produce the maps described in this paper (see 'Methods' section below), other SVG/Flash mapping tools available today for publishing maps created in desktop GIS (Geographic Information Systems) include GéoClip  , SVGMapMaker  , MapViewSVG  , and SVGMapper  . The latter two tools (MapViewSVG and SVGMapper) are specific to ESRI ArcView GIS. Table  2  provides an overview of the features of GeoReveal, GéoClip, and SVGMapMaker.Overview of the features of GeoReveal, GéoClip, and SVGMapMakerGeoRevealGéoClipSVGMapMakerA quick comparison of three tools available today for producing interactive SVG and Flash maps from desktop GIS projects: GeoReveal (from Graphical Data Capture Ltd, London, UK –  ), GéoClip (from eMc3, a young company based in Toulouse, France –  ), and SVGMapMaker (from TETRAD Computer Applications Inc, Bellingham, WA, USA –  ).Conclusions Using GeoReveal v1.1 for Windows, we produced Web-based interactive choropleth maps of diagnoses of STDs by PCT in London for the years from 1997 to 2003  . These maps are in SVG format and require a freely available Adobe SVG browser plug-in to be displayed. They are based on data obtained from the House of Commons Hansard Written Answers for 15 October 2004. They show steadily rising rates of STDs in London over the covered seven-year period. Also, one can clearly see on the maps that PCTs located in central London had the highest numbers of STD diagnoses throughout the mapped seven years. A companion bar chart allows users to instantly compare the STD figure of a given PCT for a given year against the average figure for all 25 mapped PCTs for the same year, and also compare those figures across all seven years. The maps offer users a rich set of useful features and functions, including the ability to change the classification method in use, the number of ranges in the map, and the colour theme, among others. We also presented a quick review of some of the tools available today for creating interactive vector graphics maps from desktop GIS projects. Wizard-driven tools like GeoReveal have made it very easy to transform complex raw data into valuable decision support information products (interactive Web maps) in very little time and without requiring much expertise. The resultant interactive maps have the potential of further supporting health planners and decision makers in their planning and management tasks by allowing them to graphically interrogate data, instantly spot trends, and make quick and effective visual comparisons of geographically differentiated phenomena between different geographical areas and over time. SVG makes an ideal format for such maps. SVG is a W3C non-proprietary, XML-based vector graphics format, and is an extremely powerful alternative to Macromedia ®  Flash and bitmap graphics.
Conclusions
Using GeoReveal v1.1 for Windows, we produced Web-based interactive choropleth maps of diagnoses of STDs by PCT in London for the years from 1997 to 2003  . These maps are in SVG format and require a freely available Adobe SVG browser plug-in to be displayed. They are based on data obtained from the House of Commons Hansard Written Answers for 15 October 2004. They show steadily rising rates of STDs in London over the covered seven-year period. Also, one can clearly see on the maps that PCTs located in central London had the highest numbers of STD diagnoses throughout the mapped seven years. A companion bar chart allows users to instantly compare the STD figure of a given PCT for a given year against the average figure for all 25 mapped PCTs for the same year, and also compare those figures across all seven years. The maps offer users a rich set of useful features and functions, including the ability to change the classification method in use, the number of ranges in the map, and the colour theme, among others.We also presented a quick review of some of the tools available today for creating interactive vector graphics maps from desktop GIS projects.Wizard-driven tools like GeoReveal have made it very easy to transform complex raw data into valuable decision support information products (interactive Web maps) in very little time and without requiring much expertise. The resultant interactive maps have the potential of further supporting health planners and decision makers in their planning and management tasks by allowing them to graphically interrogate data, instantly spot trends, and make quick and effective visual comparisons of geographically differentiated phenomena between different geographical areas and over time.SVG makes an ideal format for such maps. SVG is a W3C non-proprietary, XML-based vector graphics format, and is an extremely powerful alternative to Macromedia ®  Flash and bitmap graphics.Methods We used GeoReveal v1.1 for Windows to create the interactive SVG maps described in this paper. GeoReveal runs under Windows 98/NT/2000/XP and requires Microsoft ®  .NET framework v1.1 to be installed on the production machine. We started by extracting London PCT boundaries from a larger data set of all England (2001 Census PCT – post April 2002 change), which is the copyright of the Crown/Ordnance Survey  , and is freely available in both ArcView and MapInfo formats to the UK academic community from EDINA UKBORDERS service with the support of the ESRC and JISC  . We also prepared a spreadsheet containing data about the number of STDs recorded in each London PCT between 1997 and 2003 using data from [ 2 ]. The two files were merged using MapInfo Professional v7.5  , creating a MapInfo .TAB file. This file was exported to MID/MIF format, the format that files need to be in, in order to be used by GeoReveal. We created our presentation (the interactive SVG Web maps) using the GeoReveal Wizard; an eight-step process that allows users to create a fully interactive SVG page. Introduction: setting the output directory The first Wizard dialog that must be completed is the 'Introduction' dialog, which is used to specify the directory to which the final GeoReveal output files will be saved (Figure  3 ). Figure 3 Screenshot of the 'Introduction' dialog.  Screenshot of the 'Introduction' dialog in GeoReveal Wizard. For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Introduction: setting the output directory'. To select the output directory, we clicked the 'Browse' button and in the resulting file browse dialog, we selected the required directory and clicked 'OK'. To move to the next step, we clicked 'Next'. Wizard step 1: choosing the template The first Wizard step is the 'Choose Template' dialog (Figure  4 ). This dialog is used to specify general settings for a GeoReveal presentation. Figure 4 Screenshot of the 'Choose Template' dialog.  Screenshot of the 'Choose Template' dialog in GeoReveal Wizard (Wizard Step 1 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 1: choosing the template'. We selected the template to be used. Ten templates are provided; four that include a bar chart, four that include a pie chart and two that have no chart. With our London PCT STD data, the most appropriate is a bar chart template. We selected a logo image to be added to the top-left corner of our GeoReveal page. We clicked the 'Browse' button and selected the required file – in this instance, a University of Bath logo has been used. We then specified the title of the GeoReveal page. This title is placed next to the logo at the top of the output page (see the logo and title at  . Finally, we selected the title colour and page background colour. To move to the next step, we clicked 'Next'. Wizard step 2: selecting the main map data The second step is the 'Select Main Map Data' dialog (Figure  5 ). This dialog is used to specify settings for the main GeoReveal map. Figure 5 Screenshot of the 'Select Main Map Data' dialog.  Screenshot of the 'Select Main Map Data' dialog in GeoReveal Wizard (Wizard Step 2 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 2: selecting the main map data'. We selected the MID/MIF file that contains the statistics that will form the main map in our GeoReveal page by clicking the 'Browse' button and choosing the required file. We selected the field from this MID/MIF file that will be used for ToolTips. A ToolTip (or MapTip) is the piece of text that is displayed when the mouse cursor is hovered over a region in the map. In this instance, the PCT Name field has been selected. Users can also choose to turn the information box on or off. When it is turned on, a user can click a region in the map to display a dialog containing all information held within the MID/MIF file about that region (Figure  2 ). Finally, we selected the background colour and highlight colour for the map. The highlight colour is the colour a map region (an individual PCT area in our case) will be displayed in when the mouse cursor hovers over it. To move to the next step, we clicked 'Next'. Wizard step 3: selecting the overview map data The third step is the 'Select Overview Map Data' dialog (Figure  6 ). This dialog is used to specify settings for the GeoReveal overview map. Figure 6 Screenshot of the 'Select Overview Map Data' dialog.  Screenshot of the 'Select Overview Map Data' dialog in GeoReveal Wizard (Wizard Step 3 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 3: selecting the overview map data'. We selected the MID/MIF file to be used for the overview map by clicking the 'Browse' button and selecting the required file. It is possible to use the same MID/MIF file for both the main and overview maps. We selected the overview map colour and the overview rectangle colour (this rectangle shows a user where they are currently zoomed in on the main map). Additionally, users can select the background colour and border colour for the overview map panel. To move to the next step, we clicked 'Next'. Wizard step 4: selecting options controls The fourth step is the 'Select Options Controls' dialog (Figure  7 ). This dialog is used to specify settings for the 'Options Panel' in the presentation. Figure 7 Screenshot of the 'Select Options Controls' dialog.  Screenshot of the 'Select Options Controls' dialog in GeoReveal Wizard (Wizard Step 4 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 4: selecting options controls'. First, we selected the background map image that is to be used. We ticked the top 'Checkbox Visible' box to activate the background map option and then clicked the top 'Browse' button to select the file that will be used. This file must be a JPEG or GIF image and information is needed about its width and height in real terms, and also the bounding coordinates. Once the required file is selected, the 'Background Image Settings' dialog is displayed (Figure  8 ). In this dialog, we entered the bounding coordinates of our selected image, the height and width of the image in real terms, and specified how opaque the background map will be in the presentation. We then clicked 'OK' to confirm and return to the previous dialog (Figure  7 ). Figure 8 Screenshot of the 'Background Image Settings' dialog.  Screenshot of the 'Background Image Settings' dialog in GeoReveal Wizard. For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 4: selecting options controls'. In the 'Select Options Controls' dialog, it is also possible to: - enable a vector map option; and - select the text colour, border colour, background colour and control colour (the colour in which the fields are rendered) for the 'Options Panel'. To move to the next step, we clicked 'Next'. Wizard step 5: setting the bar chart The fifth step is the 'Set Bar Chart' dialog (Figure  9 ). This dialog is used to specify settings for the bar chart in the presentation. This dialog will differ depending on the template that was selected. In this dialog, one can: Figure 9 Screenshot of the 'Set Bar Chart' dialog.  Screenshot of the 'Set Bar Chart' dialog in GeoReveal Wizard (Wizard Step 5 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 5: setting the bar chart'. - specify the bar colour, grid colour (if the grid is enabled), text colour, background colour and border colour; - add or remove a % sign to the figures that are shown at the end of each bar. As the data being used in this presentation are absolute, the 'Show %' box should be unchecked; and - specify the opacity of the bars in the bar chart. After specifying our settings for the bar chart, we clicked 'Next' to move to the next step. Wizard step 6: setting the legend The sixth step is the 'Set Legend' dialog (Figure  10 ). This dialog is used to specify settings for the legend panel in the presentation. Users can: Figure 10 Screenshot of the 'Set Legend' dialog.  Screenshot of the 'Set Legend' dialog in GeoReveal Wizard (Wizard Step 6 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 6: setting the legend'. - specify a title and subtitle for the legend. Rather than specifying a main title, we checked the 'Use Dynamic Legend' box. When this box is checked, the title will be determined by the topic that the GeoReveal map is based on (a year from 1997 to 2003 in our case); - enable or disable the 'Highlight Range' option. If this option is enabled (as is the case in our presentation), when the mouse is hovered over a map region (PCT), the legend range that this region falls into will be highlighted; and - specify the text colour, background colour and border colour for the legend panel. After specifying our settings for the legend, we clicked 'Next' to move to the next step. Wizard step 7: setting the 'Information Panel' The seventh step is the 'Set Information Panel' dialog (Figure  11 ). This dialog is used to specify settings for the 'Information Panel' in the presentation. In the presentation, this panel displays information about the region in the map (PCT) that the mouse cursor is currently over. Users can: Figure 11 Screenshot of the 'Set Information Panel' dialog.  Screenshot of the 'Set Information Panel' dialog in GeoReveal Wizard (Wizard Step 7 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 7: setting the 'Information Panel". - enable or disable each of the information panels and select the fields from the MID/MIF file that will be used to populate each panel. A title can also be entered for each panel (in our instance, Panel 1 was enabled, has been given the title 'PCT Name' and will display the PCT Name field from the MID/MIF file); and - specify the text colour, background colour and border colour for the 'Information Panel'. We then clicked 'Next' to move to the next step. Wizard step 8: setting the 'Navigation Panel' The eighth step is the 'Set Navigation Panel' dialog (Figure  12 ). This dialog is used to specify settings for the 'Navigation Panel' in the presentation: the text colour, background colour, border colour and button colour. Figure 12 Screenshot of the 'Set Navigation Panel' dialog.  Screenshot of the 'Set Navigation Panel' dialog in GeoReveal Wizard (Wizard Step 8 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 8: setting the 'Navigation Panel". We then clicked 'Next' to move to the final step. Generating the presentation Lastly, we saved the settings for our presentation and generated an initial presentation page (Figure  13 ). The 'Wizard Final Step' dialog enables users to: Figure 13 Screenshots of the 'Wizard Final Step' dialog and final 'Build Successful' message box.  Screenshots of the 'Wizard Final Step' dialog and final 'Build Successful' message box in GeoReveal Wizard. For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Generating the presentation'. - save the settings they have just made by clicking 'Save Settings', then in the resulting dialog, browsing to the required directory and clicking 'Save'. The saved settings file enables users to restore their settings and edit the presentation at a later date; and - generate the presentation by clicking 'Finish'. A message is displayed to confirm that the presentation has been successfully generated (Figure  13 ). Clicking 'Yes' on the message box will open the page in Internet Explorer. When the presentation is created, the 'Advanced View' window is also opened. This can be used to add the finishing touches to the presentation. It contains all the options that the wizard does, along with a few advanced options. 'Advanced View': 'Legend' tab The 'Legend' tab can be used to select the legend colour schemes that will be available (Figure  14 ). In this tab, users can add and remove colour schemes using the 'Add' and 'Remove' buttons, and ensure that the legend to be first loaded is at the top. Legend schemes are provided with the GeoReveal installation, and additional ones can be created using this tab. Moreover, the number of decimal places used in the legend can be changed. For this presentation, it has been set to 0. Figure 14 Screenshot of the 'Legend' tab in the 'Advanced View' window.  Screenshot of the 'Legend' tab in the 'Advanced View' window in GeoReveal Wizard. For a detailed description of the functions available in this tab, please refer to the 'Methods' section > "Advanced View': 'Legend' tab'. 'Advanced View': 'Bar Chart' tab The 'Bar Chart' tab can be used to edit the bar chart (Figure  15 ). It is possible to add average value bars to the bar chart. When enabled, a second bar is added to each row of the chart which shows the mean value of all the data in that field, as opposed to the first set of bars showing values for the currently selected map region (PCT) alone. To enable this: Figure 15 Screenshot of the 'Bar Chart' tab in the 'Advanced View' window.  Screenshot of the 'Bar Chart' tab in the 'Advanced View' window in GeoReveal Wizard. For a detailed description of the functions available in this tab, please refer to the 'Methods' section > "Advanced View': 'Bar Chart' tab'. - we ticked the 'Show Average Value Bars' box to add average value bars to the bar chart; and - set the average bar colour and specified the opacity of the bars. 'Advanced View': 'Navigation Toolbar' tab Finally, we used the 'Navigation Toolbar' tab to edit the 'Navigation Panel' (Figure  16 ). In this tab, it is possible to add a button to the 'Navigation Panel', which when clicked, will open a simple HTML (HyperText Markup Language) page that contains information on how the GeoReveal presentation can be used and additional information about what it shows. To do this: Figure 16 Screenshot of the 'Navigation Toolbar' tab in the 'Advanced View' window.  Screenshot of the 'Navigation Toolbar' tab in the 'Advanced View' window in GeoReveal Wizard. For a detailed description of the functions available in this tab, please refer to the 'Methods' section > "Advanced View': 'Navigation Toolbar' tab'. - we enabled the help button by ticking the 'Display Help Button' box; - entered the text that will be shown on the button. In this instance, it will show 'Info'; and - selected the help file that will be used by clicking the 'Browse' button and selecting the required file. In this instance, an HTML document was created that contains hyperlinks to the PCT Web sites, and information about using the presentation (see lower information box in Figure  2 ). Regenerating the presentation We then resaved our settings by going to 'File' > 'Save Settings'. In the resulting dialog, we browsed to the required directory and clicked 'Save'. The presentation was regenerated by clicking 'File' > 'Generate SVG Page'. Finally, we uploaded all the generated final page files to our Web server (  – Figure  1 ).
Methods
We used GeoReveal v1.1 for Windows to create the interactive SVG maps described in this paper. GeoReveal runs under Windows 98/NT/2000/XP and requires Microsoft ®  .NET framework v1.1 to be installed on the production machine.We started by extracting London PCT boundaries from a larger data set of all England (2001 Census PCT – post April 2002 change), which is the copyright of the Crown/Ordnance Survey  , and is freely available in both ArcView and MapInfo formats to the UK academic community from EDINA UKBORDERS service with the support of the ESRC and JISC  . We also prepared a spreadsheet containing data about the number of STDs recorded in each London PCT between 1997 and 2003 using data from [ 2 ]. The two files were merged using MapInfo Professional v7.5  , creating a MapInfo .TAB file. This file was exported to MID/MIF format, the format that files need to be in, in order to be used by GeoReveal.We created our presentation (the interactive SVG Web maps) using the GeoReveal Wizard; an eight-step process that allows users to create a fully interactive SVG page.Introduction: setting the output directory The first Wizard dialog that must be completed is the 'Introduction' dialog, which is used to specify the directory to which the final GeoReveal output files will be saved (Figure  3 ). Figure 3 Screenshot of the 'Introduction' dialog.  Screenshot of the 'Introduction' dialog in GeoReveal Wizard. For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Introduction: setting the output directory'. To select the output directory, we clicked the 'Browse' button and in the resulting file browse dialog, we selected the required directory and clicked 'OK'. To move to the next step, we clicked 'Next'.
Introduction: setting the output directory
The first Wizard dialog that must be completed is the 'Introduction' dialog, which is used to specify the directory to which the final GeoReveal output files will be saved (Figure  3 ).To select the output directory, we clicked the 'Browse' button and in the resulting file browse dialog, we selected the required directory and clicked 'OK'. To move to the next step, we clicked 'Next'.Wizard step 1: choosing the template The first Wizard step is the 'Choose Template' dialog (Figure  4 ). This dialog is used to specify general settings for a GeoReveal presentation. Figure 4 Screenshot of the 'Choose Template' dialog.  Screenshot of the 'Choose Template' dialog in GeoReveal Wizard (Wizard Step 1 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 1: choosing the template'. We selected the template to be used. Ten templates are provided; four that include a bar chart, four that include a pie chart and two that have no chart. With our London PCT STD data, the most appropriate is a bar chart template. We selected a logo image to be added to the top-left corner of our GeoReveal page. We clicked the 'Browse' button and selected the required file – in this instance, a University of Bath logo has been used. We then specified the title of the GeoReveal page. This title is placed next to the logo at the top of the output page (see the logo and title at  . Finally, we selected the title colour and page background colour. To move to the next step, we clicked 'Next'.
Wizard step 1: choosing the template
The first Wizard step is the 'Choose Template' dialog (Figure  4 ). This dialog is used to specify general settings for a GeoReveal presentation.We selected the template to be used. Ten templates are provided; four that include a bar chart, four that include a pie chart and two that have no chart. With our London PCT STD data, the most appropriate is a bar chart template.We selected a logo image to be added to the top-left corner of our GeoReveal page. We clicked the 'Browse' button and selected the required file – in this instance, a University of Bath logo has been used.We then specified the title of the GeoReveal page. This title is placed next to the logo at the top of the output page (see the logo and title at  .Finally, we selected the title colour and page background colour. To move to the next step, we clicked 'Next'.Wizard step 2: selecting the main map data The second step is the 'Select Main Map Data' dialog (Figure  5 ). This dialog is used to specify settings for the main GeoReveal map. Figure 5 Screenshot of the 'Select Main Map Data' dialog.  Screenshot of the 'Select Main Map Data' dialog in GeoReveal Wizard (Wizard Step 2 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 2: selecting the main map data'. We selected the MID/MIF file that contains the statistics that will form the main map in our GeoReveal page by clicking the 'Browse' button and choosing the required file. We selected the field from this MID/MIF file that will be used for ToolTips. A ToolTip (or MapTip) is the piece of text that is displayed when the mouse cursor is hovered over a region in the map. In this instance, the PCT Name field has been selected. Users can also choose to turn the information box on or off. When it is turned on, a user can click a region in the map to display a dialog containing all information held within the MID/MIF file about that region (Figure  2 ). Finally, we selected the background colour and highlight colour for the map. The highlight colour is the colour a map region (an individual PCT area in our case) will be displayed in when the mouse cursor hovers over it. To move to the next step, we clicked 'Next'.
Wizard step 2: selecting the main map data
The second step is the 'Select Main Map Data' dialog (Figure  5 ). This dialog is used to specify settings for the main GeoReveal map.We selected the MID/MIF file that contains the statistics that will form the main map in our GeoReveal page by clicking the 'Browse' button and choosing the required file.We selected the field from this MID/MIF file that will be used for ToolTips. A ToolTip (or MapTip) is the piece of text that is displayed when the mouse cursor is hovered over a region in the map. In this instance, the PCT Name field has been selected.Users can also choose to turn the information box on or off. When it is turned on, a user can click a region in the map to display a dialog containing all information held within the MID/MIF file about that region (Figure  2 ).Finally, we selected the background colour and highlight colour for the map. The highlight colour is the colour a map region (an individual PCT area in our case) will be displayed in when the mouse cursor hovers over it. To move to the next step, we clicked 'Next'.Wizard step 3: selecting the overview map data The third step is the 'Select Overview Map Data' dialog (Figure  6 ). This dialog is used to specify settings for the GeoReveal overview map. Figure 6 Screenshot of the 'Select Overview Map Data' dialog.  Screenshot of the 'Select Overview Map Data' dialog in GeoReveal Wizard (Wizard Step 3 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 3: selecting the overview map data'. We selected the MID/MIF file to be used for the overview map by clicking the 'Browse' button and selecting the required file. It is possible to use the same MID/MIF file for both the main and overview maps. We selected the overview map colour and the overview rectangle colour (this rectangle shows a user where they are currently zoomed in on the main map). Additionally, users can select the background colour and border colour for the overview map panel. To move to the next step, we clicked 'Next'.
Wizard step 3: selecting the overview map data
The third step is the 'Select Overview Map Data' dialog (Figure  6 ). This dialog is used to specify settings for the GeoReveal overview map.We selected the MID/MIF file to be used for the overview map by clicking the 'Browse' button and selecting the required file. It is possible to use the same MID/MIF file for both the main and overview maps.We selected the overview map colour and the overview rectangle colour (this rectangle shows a user where they are currently zoomed in on the main map). Additionally, users can select the background colour and border colour for the overview map panel. To move to the next step, we clicked 'Next'.Wizard step 4: selecting options controls The fourth step is the 'Select Options Controls' dialog (Figure  7 ). This dialog is used to specify settings for the 'Options Panel' in the presentation. Figure 7 Screenshot of the 'Select Options Controls' dialog.  Screenshot of the 'Select Options Controls' dialog in GeoReveal Wizard (Wizard Step 4 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 4: selecting options controls'. First, we selected the background map image that is to be used. We ticked the top 'Checkbox Visible' box to activate the background map option and then clicked the top 'Browse' button to select the file that will be used. This file must be a JPEG or GIF image and information is needed about its width and height in real terms, and also the bounding coordinates. Once the required file is selected, the 'Background Image Settings' dialog is displayed (Figure  8 ). In this dialog, we entered the bounding coordinates of our selected image, the height and width of the image in real terms, and specified how opaque the background map will be in the presentation. We then clicked 'OK' to confirm and return to the previous dialog (Figure  7 ). Figure 8 Screenshot of the 'Background Image Settings' dialog.  Screenshot of the 'Background Image Settings' dialog in GeoReveal Wizard. For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 4: selecting options controls'. In the 'Select Options Controls' dialog, it is also possible to: - enable a vector map option; and - select the text colour, border colour, background colour and control colour (the colour in which the fields are rendered) for the 'Options Panel'. To move to the next step, we clicked 'Next'.
Wizard step 4: selecting options controls
The fourth step is the 'Select Options Controls' dialog (Figure  7 ). This dialog is used to specify settings for the 'Options Panel' in the presentation.First, we selected the background map image that is to be used. We ticked the top 'Checkbox Visible' box to activate the background map option and then clicked the top 'Browse' button to select the file that will be used. This file must be a JPEG or GIF image and information is needed about its width and height in real terms, and also the bounding coordinates.Once the required file is selected, the 'Background Image Settings' dialog is displayed (Figure  8 ). In this dialog, we entered the bounding coordinates of our selected image, the height and width of the image in real terms, and specified how opaque the background map will be in the presentation. We then clicked 'OK' to confirm and return to the previous dialog (Figure  7 ).In the 'Select Options Controls' dialog, it is also possible to:- enable a vector map option; and- select the text colour, border colour, background colour and control colour (the colour in which the fields are rendered) for the 'Options Panel'.To move to the next step, we clicked 'Next'.Wizard step 5: setting the bar chart The fifth step is the 'Set Bar Chart' dialog (Figure  9 ). This dialog is used to specify settings for the bar chart in the presentation. This dialog will differ depending on the template that was selected. In this dialog, one can: Figure 9 Screenshot of the 'Set Bar Chart' dialog.  Screenshot of the 'Set Bar Chart' dialog in GeoReveal Wizard (Wizard Step 5 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 5: setting the bar chart'. - specify the bar colour, grid colour (if the grid is enabled), text colour, background colour and border colour; - add or remove a % sign to the figures that are shown at the end of each bar. As the data being used in this presentation are absolute, the 'Show %' box should be unchecked; and - specify the opacity of the bars in the bar chart. After specifying our settings for the bar chart, we clicked 'Next' to move to the next step.
Wizard step 5: setting the bar chart
The fifth step is the 'Set Bar Chart' dialog (Figure  9 ). This dialog is used to specify settings for the bar chart in the presentation. This dialog will differ depending on the template that was selected. In this dialog, one can:- specify the bar colour, grid colour (if the grid is enabled), text colour, background colour and border colour;- add or remove a % sign to the figures that are shown at the end of each bar. As the data being used in this presentation are absolute, the 'Show %' box should be unchecked; and- specify the opacity of the bars in the bar chart.After specifying our settings for the bar chart, we clicked 'Next' to move to the next step.Wizard step 6: setting the legend The sixth step is the 'Set Legend' dialog (Figure  10 ). This dialog is used to specify settings for the legend panel in the presentation. Users can: Figure 10 Screenshot of the 'Set Legend' dialog.  Screenshot of the 'Set Legend' dialog in GeoReveal Wizard (Wizard Step 6 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 6: setting the legend'. - specify a title and subtitle for the legend. Rather than specifying a main title, we checked the 'Use Dynamic Legend' box. When this box is checked, the title will be determined by the topic that the GeoReveal map is based on (a year from 1997 to 2003 in our case); - enable or disable the 'Highlight Range' option. If this option is enabled (as is the case in our presentation), when the mouse is hovered over a map region (PCT), the legend range that this region falls into will be highlighted; and - specify the text colour, background colour and border colour for the legend panel. After specifying our settings for the legend, we clicked 'Next' to move to the next step.
Wizard step 6: setting the legend
The sixth step is the 'Set Legend' dialog (Figure  10 ). This dialog is used to specify settings for the legend panel in the presentation. Users can:- specify a title and subtitle for the legend. Rather than specifying a main title, we checked the 'Use Dynamic Legend' box. When this box is checked, the title will be determined by the topic that the GeoReveal map is based on (a year from 1997 to 2003 in our case);- enable or disable the 'Highlight Range' option. If this option is enabled (as is the case in our presentation), when the mouse is hovered over a map region (PCT), the legend range that this region falls into will be highlighted; and- specify the text colour, background colour and border colour for the legend panel.After specifying our settings for the legend, we clicked 'Next' to move to the next step.Wizard step 7: setting the 'Information Panel' The seventh step is the 'Set Information Panel' dialog (Figure  11 ). This dialog is used to specify settings for the 'Information Panel' in the presentation. In the presentation, this panel displays information about the region in the map (PCT) that the mouse cursor is currently over. Users can: Figure 11 Screenshot of the 'Set Information Panel' dialog.  Screenshot of the 'Set Information Panel' dialog in GeoReveal Wizard (Wizard Step 7 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 7: setting the 'Information Panel". - enable or disable each of the information panels and select the fields from the MID/MIF file that will be used to populate each panel. A title can also be entered for each panel (in our instance, Panel 1 was enabled, has been given the title 'PCT Name' and will display the PCT Name field from the MID/MIF file); and - specify the text colour, background colour and border colour for the 'Information Panel'. We then clicked 'Next' to move to the next step.
Wizard step 7: setting the 'Information Panel'
The seventh step is the 'Set Information Panel' dialog (Figure  11 ). This dialog is used to specify settings for the 'Information Panel' in the presentation. In the presentation, this panel displays information about the region in the map (PCT) that the mouse cursor is currently over. Users can:- enable or disable each of the information panels and select the fields from the MID/MIF file that will be used to populate each panel. A title can also be entered for each panel (in our instance, Panel 1 was enabled, has been given the title 'PCT Name' and will display the PCT Name field from the MID/MIF file); and- specify the text colour, background colour and border colour for the 'Information Panel'.We then clicked 'Next' to move to the next step.Wizard step 8: setting the 'Navigation Panel' The eighth step is the 'Set Navigation Panel' dialog (Figure  12 ). This dialog is used to specify settings for the 'Navigation Panel' in the presentation: the text colour, background colour, border colour and button colour. Figure 12 Screenshot of the 'Set Navigation Panel' dialog.  Screenshot of the 'Set Navigation Panel' dialog in GeoReveal Wizard (Wizard Step 8 of 8). For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Wizard step 8: setting the 'Navigation Panel". We then clicked 'Next' to move to the final step.
Wizard step 8: setting the 'Navigation Panel'
The eighth step is the 'Set Navigation Panel' dialog (Figure  12 ). This dialog is used to specify settings for the 'Navigation Panel' in the presentation: the text colour, background colour, border colour and button colour.We then clicked 'Next' to move to the final step.Generating the presentation Lastly, we saved the settings for our presentation and generated an initial presentation page (Figure  13 ). The 'Wizard Final Step' dialog enables users to: Figure 13 Screenshots of the 'Wizard Final Step' dialog and final 'Build Successful' message box.  Screenshots of the 'Wizard Final Step' dialog and final 'Build Successful' message box in GeoReveal Wizard. For a detailed description of the functions available in this dialog, please refer to the 'Methods' section > 'Generating the presentation'. - save the settings they have just made by clicking 'Save Settings', then in the resulting dialog, browsing to the required directory and clicking 'Save'. The saved settings file enables users to restore their settings and edit the presentation at a later date; and - generate the presentation by clicking 'Finish'. A message is displayed to confirm that the presentation has been successfully generated (Figure  13 ). Clicking 'Yes' on the message box will open the page in Internet Explorer. When the presentation is created, the 'Advanced View' window is also opened. This can be used to add the finishing touches to the presentation. It contains all the options that the wizard does, along with a few advanced options.
Generating the presentation
Lastly, we saved the settings for our presentation and generated an initial presentation page (Figure  13 ). The 'Wizard Final Step' dialog enables users to:- save the settings they have just made by clicking 'Save Settings', then in the resulting dialog, browsing to the required directory and clicking 'Save'. The saved settings file enables users to restore their settings and edit the presentation at a later date; and- generate the presentation by clicking 'Finish'. A message is displayed to confirm that the presentation has been successfully generated (Figure  13 ). Clicking 'Yes' on the message box will open the page in Internet Explorer.When the presentation is created, the 'Advanced View' window is also opened. This can be used to add the finishing touches to the presentation. It contains all the options that the wizard does, along with a few advanced options.'Advanced View': 'Legend' tab The 'Legend' tab can be used to select the legend colour schemes that will be available (Figure  14 ). In this tab, users can add and remove colour schemes using the 'Add' and 'Remove' buttons, and ensure that the legend to be first loaded is at the top. Legend schemes are provided with the GeoReveal installation, and additional ones can be created using this tab. Moreover, the number of decimal places used in the legend can be changed. For this presentation, it has been set to 0. Figure 14 Screenshot of the 'Legend' tab in the 'Advanced View' window.  Screenshot of the 'Legend' tab in the 'Advanced View' window in GeoReveal Wizard. For a detailed description of the functions available in this tab, please refer to the 'Methods' section > "Advanced View': 'Legend' tab'.
'Advanced View': 'Legend' tab
The 'Legend' tab can be used to select the legend colour schemes that will be available (Figure  14 ). In this tab, users can add and remove colour schemes using the 'Add' and 'Remove' buttons, and ensure that the legend to be first loaded is at the top. Legend schemes are provided with the GeoReveal installation, and additional ones can be created using this tab. Moreover, the number of decimal places used in the legend can be changed. For this presentation, it has been set to 0.'Advanced View': 'Bar Chart' tab The 'Bar Chart' tab can be used to edit the bar chart (Figure  15 ). It is possible to add average value bars to the bar chart. When enabled, a second bar is added to each row of the chart which shows the mean value of all the data in that field, as opposed to the first set of bars showing values for the currently selected map region (PCT) alone. To enable this: Figure 15 Screenshot of the 'Bar Chart' tab in the 'Advanced View' window.  Screenshot of the 'Bar Chart' tab in the 'Advanced View' window in GeoReveal Wizard. For a detailed description of the functions available in this tab, please refer to the 'Methods' section > "Advanced View': 'Bar Chart' tab'. - we ticked the 'Show Average Value Bars' box to add average value bars to the bar chart; and - set the average bar colour and specified the opacity of the bars.
'Advanced View': 'Bar Chart' tab
The 'Bar Chart' tab can be used to edit the bar chart (Figure  15 ). It is possible to add average value bars to the bar chart. When enabled, a second bar is added to each row of the chart which shows the mean value of all the data in that field, as opposed to the first set of bars showing values for the currently selected map region (PCT) alone. To enable this:- we ticked the 'Show Average Value Bars' box to add average value bars to the bar chart; and- set the average bar colour and specified the opacity of the bars.'Advanced View': 'Navigation Toolbar' tab Finally, we used the 'Navigation Toolbar' tab to edit the 'Navigation Panel' (Figure  16 ). In this tab, it is possible to add a button to the 'Navigation Panel', which when clicked, will open a simple HTML (HyperText Markup Language) page that contains information on how the GeoReveal presentation can be used and additional information about what it shows. To do this: Figure 16 Screenshot of the 'Navigation Toolbar' tab in the 'Advanced View' window.  Screenshot of the 'Navigation Toolbar' tab in the 'Advanced View' window in GeoReveal Wizard. For a detailed description of the functions available in this tab, please refer to the 'Methods' section > "Advanced View': 'Navigation Toolbar' tab'. - we enabled the help button by ticking the 'Display Help Button' box; - entered the text that will be shown on the button. In this instance, it will show 'Info'; and - selected the help file that will be used by clicking the 'Browse' button and selecting the required file. In this instance, an HTML document was created that contains hyperlinks to the PCT Web sites, and information about using the presentation (see lower information box in Figure  2 ).
'Advanced View': 'Navigation Toolbar' tab
Finally, we used the 'Navigation Toolbar' tab to edit the 'Navigation Panel' (Figure  16 ). In this tab, it is possible to add a button to the 'Navigation Panel', which when clicked, will open a simple HTML (HyperText Markup Language) page that contains information on how the GeoReveal presentation can be used and additional information about what it shows. To do this:- we enabled the help button by ticking the 'Display Help Button' box;- entered the text that will be shown on the button. In this instance, it will show 'Info'; and- selected the help file that will be used by clicking the 'Browse' button and selecting the required file. In this instance, an HTML document was created that contains hyperlinks to the PCT Web sites, and information about using the presentation (see lower information box in Figure  2 ).Regenerating the presentation We then resaved our settings by going to 'File' > 'Save Settings'. In the resulting dialog, we browsed to the required directory and clicked 'Save'. The presentation was regenerated by clicking 'File' > 'Generate SVG Page'. Finally, we uploaded all the generated final page files to our Web server (  – Figure  1 ).
Regenerating the presentation
We then resaved our settings by going to 'File' > 'Save Settings'. In the resulting dialog, we browsed to the required directory and clicked 'Save'. The presentation was regenerated by clicking 'File' > 'Generate SVG Page'. Finally, we uploaded all the generated final page files to our Web server (  – Figure  1 ).Competing interests CR and MS work for GDC (Graphical Data Capture Ltd), the company that produces GeoReveal.
Competing interests
CR and MS work for GDC (Graphical Data Capture Ltd), the company that produces GeoReveal.Authors' contributions All three authors contributed equally to this paper.
Authors' contributions
All three authors contributed equally to this paper.