Appropriateness of prescribing can be assessed by various measures and screening instruments. The aims of this study were to investigate the effects of pharmacists' interventions on appropriateness of prescribing in elderly patients, and to explore the relationship between these results and hospital care utilization during a 12-month follow-up period.The study population from a previous randomized controlled study, in which the effects of a comprehensive pharmacist intervention on re-hospitalization was investigated, was used. The criteria from the instruments MAI, STOPP and START were applied retrospectively to the 368 study patients (intervention group (I) n = 182, control group (C) n = 186). The assessments were done on admission and at discharge to detect differences over time and between the groups. Hospital care consumption was recorded and the association between scores for appropriateness, and hospitalization was analysed.The number of Potentially Inappropriate Medicines (PIMs) per patient as identified by STOPP was reduced for I but not for C . The number of Potential Prescription Omissions (PPOs) per patient as identified by START was reduced for I but not for C . The summated score for MAI was reduced for I but not for C . There was a positive association between scores for MAI and STOPP and drug-related readmissions (RR 8–9% and 30–34% respectively). No association was detected between the scores of the tools and total re-visits to hospital.The interventions significantly improved the appropriateness of prescribing for patients in the intervention group as evaluated by the instruments MAI, STOPP and START. High scores in MAI and STOPP were associated with a higher number of drug-related readmissions. Inappropriate prescribing causes substantial morbidity and is a clinical and economical burden for patients and society Our research group has previously reported the effects of a comprehensive pharmacist intervention, directed towards patients 80 years or older, on hospitalization and the associated costs The prospective RCT comparing patients receiving standard (non-pharmacist) care with those receiving enhanced, more comprehensive services where a pharmacist was part of the health-care team has been described in detail previously STOPP consists of 65 commonly encountered instances of potentially inappropriate prescribing in older people, including drug-disease interactions, irrational prescribing and drugs that are known to increase risks  for the elderly. The criteria identify Potentially Inappropriate Medications (PIMs). START deals with the problem of underprescribing, i.e. failure to prescribe drugs that are indicated, and consists of a list of 22 specific, evidence-based prescribing indicators that each detects Potential Prescription Omissions (PPOs). Both STOPP and START are arranged according to relevant physiological systems for ease of use and each PIM and PPO generates one point; i.e. the scoring is not weighted. In this study, the numbers of PIMs and PPOs were measured on admission and at discharge.Is there an indication for the drug? Is the dosage correct? Is the drug the least expensive alternative? When the answer to the question indicated inappropriateness, a score was assigned to the drug. The questions had weighted scores; lack of effectiveness scored 3 points, for example, while drug-drug interactions scored 2 points and duplication of drugs scored 1 point. An MAI score for each drug, the “drug score”, was calculated by weighting and adding the scores. A summated MAI score was also obtained for each patient, the “patient score”, by adding the scores for each drug for that patient's regimen.MAI contains 10 questions that are applied to each drug. The questions, formulated without reference to specific drugs or diseases included: For all three instruments, a higher score indicated inappropriate prescribing.http://www.janusinfo.se/sfinx/interactions/index_menus.jsp) to make sure no clinically relevant drug-drug interactions were missed. The patients' drug therapy was assessed twice: on the first day of the hospital stay (after admission and before any recommendations from the pharmacists had been presented to the physicians) and on the day of discharge from hospital. All prescribed drugs with pharmacologically active ingredients were included in the analyses; thus prescribed preparations such as moisturizing creams and saline for catheter flushing were excluded based on this rule. The renal function of all patients was estimated using the Cockroft and Gault equation.One clinically experienced pharmacist (UG) applied the criteria from MAI, STOPP and START retrospectively to data from the electronic case notes of the 368 included patients . The patients' medication administration records (MARs) from all hospital visits, laboratory data and electronic medical notes  were available. All drugs were entered into an interaction database  on admission and at discharge. The results for the intervention group were compared to those for the control group. For the second aim of the study, the data were analyzed without taking the group assignment into consideration. The primary outcome measure was the extent of utilization of hospital-based care (the number of visits to the ED and readmissions) during the 12 months after the index admission. The secondary outcome measure was the number of drug-related readmissions to hospital during the same period.Comparisons between the intervention and control groups with respect to changes from admission to discharge in the scores of the different instruments were performed, using rank analysis of covariance The control and intervention groups were well balanced regarding age, gender, diagnoses and social circumstances .The change from admission to discharge in MAI, STOPP and START scores differed significantly between the intervention and control groups. On average, the intervention group had lower scores at discharge than admission, while the control group had higher or unchanged scores at discharge compared to admission . The resBetween admission and discharge, the MAI, STOPP and START scores improved in 60%, 42% and 21%, respectively, in the intervention group compared to 11%, 8% and 4% of patients, respectively, in the control group . In contFor the 368 patients, none of the scores for MAI, STOPP or START were associated with the primary clinical outcomes, involving the total number of visits to hospital or the number of readmissions . HoweverIn contrast, scores for both MAI and STOPP correlated with drug-related readmissions . For MAIThere was no association between the instruments and visits to the ED (data not shown).Improvements in the appropriateness of prescribing, defined by process measures, by introducing a pharmacist intervention have been demonstrated in several previous studies Of the available criterion-based instruments available, we chose to use STOPP and START since they are recently developed, validated instruments, which have not yet been extensively tested but which appear promising in many ways; they are organized according to therapeutic area and they can be quickly and easily applied Instruments for assessing the quality of prescribing should ideally be valid, reliable, sensitive, specific, and feasible Although STOPP and START were developed to complement each other, the creators of the instruments have, to our knowledge, not used or analyzed the combined scores. In our study, when the PIMs and PPOs were combined, the vast majority (84%) of points for inappropriateness at discharge were from the STOPP criteria. Because the instruments were not equally represented, we chose not to combine them in a single measure, although it was tempting to include all aspects of appropriate prescribing into one score. It is also important to consider that the MAI does not take underprescribing into account and therefore does not cover all aspects of inappropriate prescribing. An area for future research is therefore to find ways to combine these measures in order to use a multidimensional approach.In the control group, the proportion of patients with deteriorated MAI, STOPP and START scores at discharge was larger than the proportion with improved scores. A possible reason for this could be that the focus was on treating the current cause of admission, and hence drugs were added without a thorough review of previous, on-going prescriptions. The situation was the opposite for the intervention group, with more patients having improved scores at discharge. This confirms that the introduction of a pharmacist to the health-care team encourages prescribing that takes all the diagnoses and other medications into account.The association between higher scores in STOPP and MAI and an increase in the number of drug-related hospital admissions was statistically significant with a RR of 1.34 for STOPP and 1.04 for MAI. Are these findings clinically relevant? On average, the MAI scores for patients in the intervention group were reduced by 3.5, which indicated a 31.5% lower risk of a drug-related readmission at follow-up. Similarly, the mean reduction of 0.5 in STOPP score in the intervention group indicated a 17% lower risk of a drug-related readmission at follow-up. Previous studies have used drug-related revisits to hospital as an outcome measure for interventions that aim to improve quality of prescribing The MAI, STOPP and START assessments were conducted by a single pharmacist. This limits the reproducibility of the study, but it also resulted in a more uniform assessment. Our study only included patients aged 80 years or older, while most other similar studies have included patients aged 65 years or older. This impedes comparison of results. Barry et al. found that approximately 57% of elderly patients admitted to hospital had at least one appropriate drug omitted, as assessed by START Since the clinical pharmacist intervention in the RCT consisted of a number of elements and the screening instruments only evaluate the drug review part of the intervention, the reduction in hospital visits that was observed cannot be assumed to be directly due to the MAI, STOPP and START scores. The interventions that aimed to increase the patients' knowledge of and adherence to drug treatment and the reduction in medication errors were for example not taken into consideration. The key elements of the RCT, that were associated with improvements to the appropriateness of prescribing, were the focus on and knowledge of prescribing for the elderly that was brought into the care team by the clinical pharmacists, the close working relationship among doctors, nurses and pharmacists and the extensive communication with the patients. In order to improve the overall quality of drug use, it is necessary not only to focus on pharmacological appropriateness but also to consider the wants and needs of the individual patient. This is most important to keep in mind, both when designing drug review interventions and when assessing the appropriateness of prescribing.There is currently no validated instrument that covers all relevant aspects of appropriate prescribing. The three instruments used in this study all focus on different aspects of appropriate prescribing but none of them take the patients' views, wishes or adherence to treatment into consideration. However, when used together, the three instruments present a multidimensional assessment that evaluates aspects of both under-, over-, and mis-prescribing.The addition of a comprehensive pharmacist service to standard care significantly improved the appropriateness of prescribing for patients in the intervention group that participated in the RCT, as evaluated by the screening instruments MAI, STOPP and START. High MAI and STOPP scores at discharge were associated with a higher number of drug-related readmissions; however, no statistically significant relationship was found between the scores and the total number of re-visits to hospital during a 12-month follow-up period.


The aim of this study was to see if dental personnel with previous exposure to metallic mercury have later developed disturbances in cognitive function. Ninety-one female participants who had been selected from a previous health survey of dental personnel were investigated neuropsychologically within the following domains: motor function, short-term memory, working memory, executive function, mental flexibility, and visual and verbal long-term memory. The scores were mainly within normal ranges. Relationships between an exposure score, the duration of employment before 1990, and previously measured mercury in urine as independent variables and the neuropsychological findings as dependent variables, were analyzed by multiple linear regression controlling for age, general ability, length of education, alcohol consumption, and previous head injuries. The only relationship that was statistically significant in the hypothesized direction was between the previously measured urine mercury values and visual long-term memory, where the urine values explained 30% of the variability. As the study had a low statistical power and also some other methodological limitations, the results have to be interpreted with caution. Even so, we think it is right to conclude that neuropsychological findings indicative of subsequent cognitive injuries are difficult to find in groups of otherwise healthy dental personnel with previous occupational exposure to mercury. The acute toxic effects of metallic mercury on CNS functions have been known for centuries. Symptoms of mercury poisoning comprise tremor, reduced psychomotor speed, paresthesia and a fairly distinct constellation of psychological symptoms, namely nervousness, shyness, blushing, irritability, and lability of mood. Mild forms of this syndrome are termed micromercurialism, whereas more grave conditions entailing psychotic symptoms are called erethism . As a muAlthough the effects of acute mercury poisoning are well described and documented, the risk of long-term effects on the CNS from chronic low-level exposure is still debated. Previous studies of long-term effects from relatively low level exposures have been performed in different groups of mercury-exposed workers . In someSome studies of cognition and neuropsychological function in industrial workers exposed to mercury vapours have shown small, but statistically significant decreases in such domains as fine motor coordination, vigilance, psychomotor speed and visual memory , while oIn studies of the possible negative effects of mercury released from dental amalgam, no association between amalgam fillings and performance on tests of cognitive function was found in a homogenous group of elderly women .Dental personnel have been exposed to metallic mercury when handling amalgam for teeth restoration. The degree of exposure has varied with the extent of the use, work performance and physical working conditions. In some countries, including Norway, a special kind of copper amalgam was used from the 1950s to the end of the 1980s for restoring deciduous teeth in particular. The procedure for preparing copper amalgam for use entailed the heating of solid tablets containing 70% metallic mercury for up to more than 200 °C. This could entail a substantial exposure to mercury vapor. Until the 1980s it was also customary for many of the assistants to handle amalgam in their bare hands in order to keep it soft while it was being used .During the last decades there have been several studies that have shown various deleterious neuropsychological effects in current dental personnel in areas such as short-term memory , psychomThe aim of our study was to see if dental personnel with previous exposure to metallic mercury have later developed disturbances in such cognitive domains as psychomotor speed, attention, and verbal and visual long-term memory, which was hypothesized to be the case.In a previous survey 856 female dental personnel under the age of 70 from central Norway had answered a standardized questionnaire called Euroquest that was developed to survey persons with neurotoxic exposures , thyreoidea stimulating hormone (TSH), alanine transaminase, cobolamin, folate, and serum creatinine. Each subject was tested by a clinical neurpsychologist (HS) on the same day as they were interviewed by one of the occupational physicians. When testing, the neuropsychologist did not know anything about the background data, health status or exposure status of the participants, and the same test procedure was followed for all. Depending on individual differences in working speed, the testing took from 1.5 to 2 hours, including a short break.In order to be able to consider possible confounding from psychological complaints, the degree of subjective emotional symptoms was assessed by use of the SCL-90-R .In order to look at the general intellectual ability of the participants, we used the Similarities Test and the Picture Completion Test from the WAIS III  which meThe results from the particular neuropsychological tests used were combined into cognitive domains. The test used was the Finger Tapping Test from the Automated Psychological Test System APT) , and incThe Digit Span Forward from the WAIS III  was usedThree tasks comprised this domain. In the Digit Span Backward (WAIS III), the subjects were asked to repeat the digits in the reverse order of presentation. Again, the score was the number of digits correctly repeated in reverse order.In addition, two versions of the Paced Auditory Serial Addition Task (PASAT) were used . Taped sTwo tasks were included, one subtest from the Stroop test  and the In the APT test, the subject was required to inhibit her response to a visual stimulus when presented together with a sound, but not otherwise (Go-NoGo). Two scores were calculated. One was the mean reaction time in milliseconds for each hand respectively, and the other was the number of failed inhibitions.The tests included were the simple auditory, simple visual and two-choice reaction time tests, all from the APT. All measures were given in milliseconds.This score was computed using the difference between the Trail Making Test B (TMT B) and Trail Making Test A (TMT A). This was done to correct for baseline motor performance . StandarThe California Verbal Learning Test II (CVLT-II) was used . The tesThe Doors Test  is a tas2. Center Frequency, measured in Hz, is the mean of the accelerations in the frequency area 0.9 to 15.0 Hz during the registration period. The standard deviation of the Center Frequency concerns the degree of coordination of the tremor. Lastly, the Harmonic Index refers to a comparison between the frequency pattern of the tremor and the pattern of one single oscillation.Tremor was recorded using the Tremor Pen . Tremor z-scores based on means and standard deviations from the current sample before they were added together in the seven different cognitive domains. Possible relationships between the three chosen independent exposure variables  and the dependent variables (the cognitive domains) were analyzed by multiple linear regression. For exploration of possible confounding factors, and to build models for the final analyses, we first used a model with age, general ability, length of education, number of own amalgam fillings, alcohol consumption, systolic blood pressure, the occurrence of cardiovascular disease, epilepsy, hypothyreosis, previous head injuries, and the SCL-90-R depression score  . Because the scores for each particular neuropsychological test could be on different scales and could have both positive and negative values, the test scores were transformed into on score  and 2 asMean values of the neuropsychological tests were compared either to existing norms or relevant normal controls from other studies.The study was approved by the ethical committee for medical research in Central Norway, and we had a license for personal registrations from the Norwegian Social Science Data Services. The conduct of the study was deemed to be in accord with the Helsinki declaration on medical research ethics.Among the 91 participants there were 16 dentists, 69 dental assistants, and 6 who belonged to other occupational groups within dental health care. Blood samples, which were analyzed for free thyroxin (FT4), thyreoidea stimulating hormone (TSH), alanine transaminase, cobolamin, folate, and serum creatinine, revealed values within normal ranges for all tests in all individuals. This gave an indication that the participants did not have other diseases that could impair their cognitive function, and that the eleven subjects who suffered from hypothyroidism seemed well regulated.The only hypothesized relationship between the indicators of mercury exposure and cognitive function that was found was in the regression analysis of a relationship between previously measured urinary mercury and long-term visual memory. Other exposure indicators, such as our calculated total exposure score and the length of employment in dental care prior to 1990, did not show any statistically significant relationship apart from a few that went in the inverse direction.As the participants were examined without knowledge about their health status or previous exposure situation, and relevant potential confounding factors like age, length of education, alcohol consumption, and previous head injuries were controlled for in the analyses, bias probably does not provide an explanation for the mainly negative results. In that regard it is somewhat remarkable that 12.1% of the participants reported having hypothyreosis. There can be different reasons for that, but one hypothesis that should be looked into is that the occurrence of hypothyreosis is increased in females who have been exposed to mercury. As the distribution of Euroquest scores was similar, we also believe that the subgroup was a representative selection from our initial study group. The distribution of the exposure scores in the initial study and this study also indicates that there was no serious selection bias in the neuropsychological study. One small bias might, however, have been introduced as the 26 who declined participation mainly did so because they were without any complaints and/or because they assessed their own exposure as insignificant. In regard to the neuropsychological methods that were applied, we are confident that they were relevant and sufficiently sensitive as such.One problem with the present study is, however, its low statistical power. In the primary questionnaire survey on which the present study is based, we revealed prevalences in female dental assistants of between 0.4% and 2.8% of assumed cognitive malfunction related to occupational exposure to metallic mercury (Another feature that may have influenced our results is that individual susceptibilities may be equally important determinants for chronic cognitive effects as the level of exposure as such . At the Previous studies of adverse effects of metallic mercury in currently exposed dental personnel have shown moderate effects on cognitive function  However,Another limitation in regard to the generalizability of the present study is that men were not included. There were only 227 men under the age of 70 who had participated in the initial survey. The low number would have made a stratified analysis impossible. Moreover, most of the participating men were dentists with higher education and with relatively low exposures, which could also have led to confounding as a result of different educational levels.Our finding of a relationship between previously measured urinary mercury values and a reduction in visual long-term memory is of particular interest from a neuropsychological point of view. In our study, visual memory was investigated using a recognition task with two levels of difficulty. The reduced performance was evident on both the easy and difficult parts of the Doors test , indicatSome studies have shown impairments in color discrimination and contrast sensitivity in subjects exposed to metallic mercury . It has Because of the restrictions and limitations mentioned, any interpretation of the results has to be made with caution. Even so, we find that our investigation has been carefully performed with little selection bias and a reasonable control of possible confounding factors.Based on our study and available knowledge, it seems reasonable to conclude that neuropsychological findings indicative of subsequent cognitive injuries can be difficult to find in groups of otherwise healthy dental personnel with previous exposure to metallic mercury. For further studies, we think that these have to be undertaken on subjects with both relevant cognitive complaints and sufficient exposures, and preferably, where features of individual susceptibility are also taken into account.


There is no doubt that the dramatic worldwide increase in obesity prevalence is due to changes in environmental factors. However, twin studies suggest that genetic differences are responsible for the major part of the variation in body mass index (BMI) and other measures of body fatness within populations. Several recent studies suggest that the genetic effects on adiposity may be stronger when combined with presumed risk factors for obesity. We tested the hypothesis that a higher prevalence of obesity and overweight and a higher BMI mean is associated with a larger genetic variation in BMI.The data consisted of self-reported height and weight from two Danish twin surveys in 1994 and 2002. A total of 15,017 monozygotic and dizygotic twin pairs were divided into subgroups by year of birth (from 1931 through 1982) and sex. The genetic and environmental variance components of BMI were calculated for each subgroup using the classical twin design. Likewise, the prevalence of obesity, prevalence of overweight and the mean of the BMI distribution was calculated for each subgroup and tested as explanatory variables in a random effects meta-regression model with the square root of the additive genetic variance  as the dependent variable.The size of additive genetic variation was positively and significantly associated with obesity prevalence (p = 0.001) and the mean of the BMI distribution (p = 0.015). The association with prevalence of overweight was positive but not statistically significant (p = 0.177).The results suggest that the genetic variation in BMI increases as the prevalence of obesity, prevalence of overweight and the BMI mean increases. The findings suggest that the genes related to body fatness are expressed more aggressively under the influence of an obesity-promoting environment. The prevalence of obesity has increased at epidemic rates in most parts of the world in the last decades, and in the USA recent data show that more than a third of all men and women are now obese 2]).The study population originates from The Danish Twin Registry (DTR), which contains information on virtually all twins born in Denmark since 1870 2 or BMI>50 kg/m2). Thus, a total of 7,912 twin pairs were available for the analysis, including 1,664 MZ male, 2,082 DZ male, 1,974 MZ female and 2,192 DZ female twin pairs (2 or BMI>50 kg/m2) resulting in 7,105 twin pairs for the analysis including 1,330 MZ male, 1,708 DZ male, 1,831 MZ female and 2,236 DZ female twin pairs  were not used in the calculation of the variance components, and additional 93 pairs were excluded due to extreme BMI values (BMI<15 kg/min pairs . The 200in pairs .The data within each defined subgroup (sex-birth year strata) were analysed through quantitative genetic modelling, in which the total phenotypic variation of a trait is divided into variation due to environmental factors and variation caused by genetic differences between individuals. The disentangling of genetic and environmental variation is made possible through structural equation modelling of co-variation within pairs of different types of family relations. The relations included in the modelling are genetically informative if they differ in the degree of genetic or environmental similarity The genetic variance can further be decomposed into parts due to additive effects of alleles at multiple loci (A) and due to dominance effects (D) at multiple loci, respectively. Epistatic effects refer to interaction between genes at different loci and will usually be modelled as part of dominant genetic effects. However in the case of linked loci, epistatic effects will be modelled as additive genetic effects since the genes segregate together and form a unit. The environmental variance can be divided into factors shared by co-twins (C) and factors that are unique to each twin individual including also any measurement error (E). Hence, total phenotypic variation can be decomposed into four components: the additive genetic (A), dominant genetic (D), common environmental (C), and specific environmental (E) variance component. Since we only have data on twins reared together, the D and C components cannot be estimated simultaneously and thus the model fit of the ACE and ADE models were compared As noted above, the study population was stratified by sex and birth year giving a total of 164 subgroups. The division into birth cohorts ensures that the gene pool is similar across subgroups and at the same time allows variation in the explanatory variables. Hence, any differences in variance components between subgroups, when controlling for age and sex, are caused by environmental factors and not by differences in genetic background. The variance components were subsequently calculated for each subgroup. To simplify the analyses and interpretation of the variance components estimates, opposite sex dizygotic twin pairs were excluded from the analysis.2, respectively The obesity prevalence, overweight prevalence and mean BMI were calculated for each subgroup defined by sex and year of birth . The underlying assumption is that an obesity promoting environment will result in a higher prevalence of obesity and overweight and a higher mean BMI The prevalence of obesity and overweight and the BMI mean were tested as explanatory variables for the (square-root of the) additive genetic variance (AGV), using random effects meta-regression modelling (REMR) The analyses included 6,799 monozygotic and 8,218 dizygotic eligible twin pairs. Summary statistics of BMI by survey, zygosity and sex is reported in 2.The explanatory variables and AGV are reported for each subgroup in A large proportion of twins from the first survey were also present in the second survey (about 72%). This is a potential problem in the statistical modelling since not all observations are independent. Hence, in order to determine whether the overlap would bias the results, we carried out the same analyses excluding the overlap between the two surveys. We found that the results were not statistically significantly different when overlaps were excluded.We found that both the additive genetic and unique environmental standard deviations were positively associated with prevalence of obesity and the mean of the BMI distribution. The association with overweight, although not statistically significant, was also positive. Since the gene pool can be assumed to be comparable across subgroups, the findings suggest that the environmental influence, causing a higher prevalence of obesity and a higher BMI mean, increases both the genetic and environmental variance of BMI. Hence, an obesity-promoting environment is possibly modifying the genetic variance in BMI. As will be argued later, the current findings may be comparable with recent findings on specific environmental modifiers of genetic variance.Although not explicitly a part of the hypothesis, it is worth noting that also the environmental variance was higher in subgroups with a higher prevalence of obesity and mean BMI . This su2 increase in BMI. This association was significantly more pronounced in physically inactive (0.21 kg/m2) than in physically active (0.13 kg/m2) individuals. Environmental influences other than physical activity are possibly contributing to changes in the expression of genes related to body fatness as well. For example, fat and carbohydrate, but not protein, intake was found to interact with the effect of FTO-gene on BMI Previous studies have found higher AGV of BMI and waist circumference among individuals with a low, compared to high, level of physical activity The mechanisms involved in the increase in AGV could occur on at least two separate levels. One possibility is that the changes in genetic variation reflect changes in gene regulation at a molecular genetic level. Alternatively the associations could be the result of more distal environmental influences on gene expression. For example, conceive of a genotype that is associated with high body fatness due to increased appetite. If the individual carrying the genotype lives in an environment where food is limited, the particular genotype will not be allowed full expression on body fatness. Nevertheless, changes in environmental conditions, allowing easier access to high energy-dense foods, would lead to an increased expression of the particular genotype on body fatness. This, in turn, could result in an increase in AGV of body fatness. In this light, the current results could reflect differences in environmental conditions across birth cohorts, enabling or restricting the expression of one or several genes associated with BMI.Gene-environment correlation (rGE) is a phenomenon closely related to the possible distal regulations of gene-expression. rGE refers to a phenomenon in which the environmental exposure of an individual is related to his genotype. For example, a certain personality trait, which is genetically influenced, may result in an individual preference for an urban environment. If the urban environment is more obesogenic than the rural, then this rGE would not be distinguishable from other types of genetic effects on adiposity. If the urban environment becomes increasingly obesogenic with time this could increase the genetic variance and hence explain the current results. Finally it should be noted that the mechanisms could occur at both levels and in theory act synergistically and perhaps even cancel each other out.The value of the current study has both a practical and theoretical dimension. We will consider the practical value first. Since the additive genetic variance component is an aggregate of the effect of all genetic loci, the regression models can potentially be used as a tool to optimize the search for adiposity related genes. It is plausible that by selecting populations with model parameters giving the highest predicted additive genetic variance, we are improving our chances of locating genes related to body fatness. Furthermore, it is possible that the increase in additive genetic variance across different levels of obesity prevalence reflects the initiation of new genes, not active at lower exposure levels. In this case the model could improve not only efficiency, but also the possibility of locating new loci not previously discovered. It can therefore be argued that, based on the current findings, the genome wide association studies should be carried out in populations with a high prevalence of obesity, high prevalence of overweight and a high mean BMI. In addition, it is worth noting that inconsistent results from genome wide association studies on obesity may, in part, result from inter-population differences in the exposure to the obesity-promoting environment.Knowledge on environmental modification of gene expression may also, in a longer term, be used in prevention or treatment of obesity. If specific modifiable environmental factors are associated with the effect of particular genetic variants, the results could possibly be used as a measure of prevention or treatment in an individualised form. It is, however, possible that gene-environment interaction studies, on a molecular level, will show limited success in explaining the bulk of the variation, as the case has been with simple genome-wide association studies. An alternative approach would be to imply knowledge of gene-environment interaction on a population-based level. If we, through twin and family studies, are able to identify modifiable environmental factors, which have a considerable impact on genetic variance of adiposity, we can use the results in population level prevention without knowledge of the effect on particular genes. However, in this case the approach to obesity prevention will, in practice, not be different from the current public health efforts, unless new environmental modifiers, not previously considered risk factors of obesity, are discovered.The theoretical value of this work lies in the realisation that the expression of adiposity-related genes is highly dependent on the environmental context. The increase in genetic variance was estimated to around 3.3% for every one percentage point increase in prevalence of obesity. This translates into a 33.3% increase with a 10 percentage point increase in the prevalence of obesity, which is seen in many countries. Hence, based on the current statistical modelling it is possible that the genetic standard deviation has increased considerably in many places. This implies that gene-environment interaction may be responsible for a large part of the genetic variance and that the genetic architecture of obesity should not be considered independent from the environmental context. Hence, there may be a substantial benefit in, to a further extent, incorporating gene-environment interaction into both the molecular and the quantitative genetic modelling of the genetic architecture of obesity.The current study is based on data from two cross-sectional surveys. If the changes in prevalence of obesity were only a product of calendar time, there would be no variation in exposure within subgroups in the same survey. However, Olsen et al. showed that the Danish obesity epidemic is most likely more directly associated with birth cohorts than with calendar time An important strength in the current study design is that the gene pool across subgroups can be expected to be the same, since the genetic architecture is unrelated to year of birth. This implies that any differences in genetic variance are caused by differences in environmental influence and not by systematic differences in genetic material between subgroups. In other words, the discovered association between the explanatory variables and the genetic variance component may be attributed to environmental modification of the effect of genes related to BMI.The current study is also subject to limitations. After excluding incomplete twin pairs, opposite sex twin pairs and twin pairs with extreme BMI values only 47% of the individuals from the total sample are included in the analyses. We found the BMI variation to be slightly higher among opposite sex twin pairs. Thus, theoretically, the results may be biased by selection of individuals who are different from the total original sample. However, our main interest is in the genetic variance. Biologically there is no reason to assume that various types of siblings differ in terms of their gene pool, why this limitation is unlikely to be critical in the current study. Height and weight was self-reported which is a less accurate method to assess BMI than standardized measurements. Since measurement errors are modelled as unique environmental variance it is likely that the heritability of BMI would be underestimated. However, when estimating the AGV we are using the raw estimate, which, in contrast to heritability, is not dependent upon the environmental variance component. Another issue is that the obesity-promoting environment was measured indirectly through the obesity prevalence, overweight prevalence and mean BMI. Thus, the results do not clarify which specific factors in the environment induce the observed changes. Although previous studies give evidence of physical activity as a modifier, it is possible that other factors are involved as well. Likewise, the study is limited to addressing general changes in gene expression and more work is needed on a molecular genetic level in order to elucidate the specific genetic units involved. Although the study was designed to eliminate confounding from differences in the gene-pool between strata (by stratifying by birth year), residual confounding can never be completely ruled out in observational studies. For example, age may confound the results if the particular parameterization of the age-effect does not capture the relationship between age and the AGV. Another limitation is that analyses were carried out in Denmark where the prevalence of obesity is relatively low compared to, for example, the USA In summary, our study shows that the additive genetic and environmental variance is positively associated with prevalence of obesity, prevalence of overweight and the mean of the BMI distribution, although not statistically significant for overweight. The results suggest that the obesity-promoting environment enhances the effect of genes related to body fatness. The findings may be related to previous studies showing a higher genetic variance and a larger effect of the FTO-gene among individuals with a low, compared to high, physical activity level. The association could reflect changes in genetic regulation at a molecular genetic level or be the result of more distal environmental restrictions on gene expression. In near term the results may be utilized in the search for new candidate genes by defining study populations that give the highest predicted genetic variance. In a longer term the research into gene-environment interaction may have a potential in future obesity prevention, either as part of an individualized or a population-based approach.Table S1Subgroups used in meta-regression analyses. Subgroups defined by stratifying the twin sample by survey, sex and year of birth. For each subgroup the summary statistics , additive genetic variance (AGV) and number of twin pairs (N) is reported.(DOC)Click here for additional data file.


Against this background, the ARRIVE guidelines were published in PLoS Biology in July 2010.8 We strongly support this initiative and believe it will make an important contribution to improving the reporting of animal studies.Hundreds of experiments in which animals are used to answer biomedical research questions are performed and published every month. Although well-designed and performed animal experiments are a necessary condition for successful translational research, many papers involving animal experimentation are still incomplete in their reporting.et al. A gold standard publication checklist to improve the quality of animal studies, to fully integrate the three Rs, and to make systematic reviews more feasible. Altern Lab Anim 2010;38(2):167–82. This checklist was presented and discussed at the World Congress on alternatives and animal use in the life sciences in Rome in 2009 and published in ATLA in May 2010, a few months before the ARRIVE guidelines appeared.In our view, guidelines are not only necessary for increasing the quality of reporting of completed animal studies, but are also essential for optimal design and execution of new animal experiments, and thus improved scientific quality. With these goals in mind, we developed the Gold Standard Publication Checklist (GSPC): Hooijmans Given their partly similar aims, the GSPC has some overlap with the ARRIVE guidelines. However, the GSPC describes certain items in more detail, for instance the housing conditions , nutrition  and water. These detailed descriptions in the checklist help scientists to include all the specific items necessary for planning, designing and performing animal experiments in the most optimal way, and to improve repeatability of and control variation within experiments, through which the quality of research improves and the number of animals needed in an experiment diminishes. In addition, the GSPC paper highlights the importance of reporting husbandry conditions and basic principles of the design of animal experiments by providing an overview of the literature on how and when interference with experimental results may occur. Last but not least, the GSPC is presented as a checklist, and therefore well-ordered and easy to use when designing and executing animal experiments.10 SRs can be defined as a literature review focused on a single question that tries to identify, appraise, select and synthesize all available high-quality research evidence relevant to that question. These SRs lead to better interpretation of the already existing scientific results from animal experiments, through which a better translation to the clinic and more guarantees for patient safety become reality. Furthermore, unnecessary duplication of animal experiments, and thereby unnecessary animal use and time loss, will be prevented. SRs are already standard practice in clinical studies and it is about time that they will become standard practice in the field of animal studies as well.11The use of guidelines for designing, executing and reporting of animal experiments (like the ARRIVE guidelines or the GSPC) will also make systematic reviews (SRs) and meta-analyses of publications on animal studies more feasible.To conclude, in order to make SRs feasible and to improve not only the reporting but also the planning, design and execution of animal studies, we strongly recommend all scientists involved in animal experimentation and editors of journals publishing animal studies to make use of the GSPC and/or the ARRIVE guidelines.


Mycobacterium avium subsp. paratuberculosis (MAP) infection causes in ruminants a regional chronic enteritis that is increasingly being recognized as a significant problem affecting animal health, farming and the food industry due to the high prevalence of the disease and to recent research data strengthening the link between the pathogen and human inflammatory bowel disease (IBD). Control of the infection through hygiene-management measures and test and culling of positive animals has to date not produced the expected results and thus a new focus on vaccination against this pathogen is necessary. This review summarizes all vaccination studies of cattle, sheep or goats reporting production, epidemiological or pathogenetic effects of vaccination published before January 2010 and that provide data amenable to statistical analyses. The meta analysis run on the selected data, allowed us to conclude that most studies included in this review reported that vaccination against MAP is a valuable tool in reducing microbial contamination risks of this pathogen and reducing or delaying production losses and pathogenetic effects but also that it did not fully prevent infection. However, the majority of MAP vaccines were very similar and rudimentary and thus there is room for improvement in vaccine types and formulations. Mycobacterium avium subsp. paratuberculosis (MAP), has been shown to cause the disease in the majority of wild and domestic ruminant species [Paratuberculosis poses a big challenge to Veterinary Medicine and in particular to ruminant production. Since the first description of the disease in 1895 in a cow from Oldenburg, Friesland, its etiological agent,  species . This mi species ,4. Even The mounting evidence showing that MAP is a factor in the pathogenesis of human inflammatory bowel disease (IBD) has increased the pressure to overcome this challenge. In spite of this, most of the undertakings are nevertheless based on the old principle that the only way to control an infectious disease is to eradicate its agent. This principle has worked well for some acute infections in times of survival struggle and profligate use of means but is increasingly difficult to apply because of demonstrated lack of efficacy and sustainability philosophy ,6. We arManagement changes to reduce the transmission rate are widely accepted strategies that are compatible with all other approaches . FurtherAlthough these measures might be viable for large dairy farms, the required changes may not be economical for many small dairy farms and are probably impossible to implement in beef cattle and sheep operations due to costs and disrupting effects. Moreover, these measures usually yield no immediate results and are easily abandoned when other productive constraints become more pressing . In summThree variants of the testing and culling strategy prevail depending on the diagnostic method used to detect infected animals: fecal culture, ELISA or Polymerase Chain Reaction (PCR). The slow turn around rate or the low sensitivity of some of these test are the major problems in the efforts to control the disease .It is generally accepted that this method detects infected animals first and is the most sensitive method ,14. SincThe ELISA test for paratuberculosis is generally considered to be highly specific, but of low sensitivity . ELISA'sThe new type of strategy, albeit sparsely implemented, is the combination of PCR analysis of feces and culling of positive animals. In theory, this strategy should detect animals early in the infection process before antibodies are developed, and thus can quickly reduce the overall bacterial burden in the farm. However, the costs and the requirement of specialized personnel are major drawbacks of this technique. Until recently costs of PCR were extremely high for its use in animal health diagnostics. Dramatic reductions in reagent prices accompanied by improvements in technique sensitivity and especially in efficient high-throughput processing of samples and extraction of nucleic acids have made this approach a valuable strategy due to its high specificity, good sensitivity, and fast turnaround time ,21. The Mycobacterium bovis (PPDbov) and Mycobacterium avium subsp. avium (PPDav). Higher reactivity to the avian tuberculin indicates infection or vaccination with avian type mycobacteria and allows to rule out mammal tuberculosis infection according to standardized criteria.Vaccination, as a control measure for paratuberculosis, is probably the less accepted strategy although it is or has been used in all countries with substantial problems with this disease ,27. It iAn additional drawback to MAP vaccination, which at least in sheep appears not to be of economical relevance , is the In summary, there are several strategies for paratuberculosis control, but there is no generalized consensus on which one or which combination of strategies should be the standard approach. In our opinion, this is in part due to the fact that paratuberculosis control programs emphasize too heavily MAP eradication.If we take a general view of our knowledge on paratuberculosis, we should point out that MAP is not a classical infectious agent fully complying with Koch's postulates. Indeed, we know that many experimental infections fail to establish the infectious agent in the intestinal tissue and to cause the disease -33. We aMultiple forms of infection can be observed in MAP infected animals. The form present in an animal will not only depend on the progression of the infection or stage of the disease, but also on many other factors including an individual's genetic resistance or susceptibility to the pathogen, age at the time of infection, and previous exposure to other environmental mycobacteria. On Figure Both live (non-attenuated and attenuated) and killed whole cell vaccines have been used against paratuberculosis. In a few cases, subunit vaccines consisting of sonicated bacteria, bacterial cell fractions or recombinant MAP antigens have been used but they have shown a much lower degree of protection ,40. MoreParatuberculosis vaccines are recommended for exclusive use in very young animals on the grounds that this is necessary to prevent infection and to decrease interfering responses with the diagnosis of tuberculosis. Actually, the experience on animals older than 1 month is rather scarce, however recent studies on the pathogenesis as well as some field data suggest that vaccination of adult or subadult animals might have some management  and therapeutic  advantages that need to be taken into account ,49. Morehttp://www.google.com) to obtain studies from doctoral dissertations and other sources. Third, literature data on vaccination trials collected over a period of 25 years at NEIKER was also examined systematically. More than half the published studies included in this meta-analysis describe field reports, which actually might give a better view of the whole problem of vaccination, since highly controlled experimental trials might be misleading because of the lack of interferences from field conditions.There is an increasing number of vaccination studies in ruminant species focused on different aspects of the use of MAP vaccines including two recent reviews on the topic ,52. The The very first report on paratuberculosis vaccination of cattle is that by Vallée and Rinjard in 1926 . It is nTaking worldwide published reports on paratuberculosis vaccination available to us but not restricted to peer-reviewed papers, we have classified the studies according to species , and type of evaluation of vaccine efficacy . We have kept only those studies were the authors reported either vaccinated versus control group or pre-vaccination versus post-vaccination cohorts in numerical terms. In all, except in one study where a scoring system was used for MAP isolation, results were presented as the frequency of positive/affected individuals over total animals in the study. We have not been overly critical on the criteria applied by authors, but instead we have assumed that they knew well the disease and that their study design was sound.All data have been transformed into a reduction percent calculated as the frequencies difference divided by the frequency in the control group. For each category of species and type of evaluation, we have calculated a size-weighted reduction average for the whole set of studies in that category. The same size-weighting method has been previously used to calculate a standard deviation in order to define the 95% confidence limits of the estimate .A total of 118 experiments from 63 reports and 14 countries have been used for the meta-analysis in this review Tables . The USAHalf of the studies are field trials where animals were naturally exposed to MAP. In these studies, results were assessed either by comparison between initial prevalence before vaccination, and final prevalence some time post-vaccination, or by following up a matched group within the same herd or flock. The later type of studies, when the control group is housed with vaccinated animals, frequently underestimates the positive effects of vaccination, because as herd immunity increases, bacterial shedding into the environment is reduced and thus the probability of a natural infection in the control group is also reduced. In three experiments the assessment was done using control unvaccinated herds, and one consisted of a questionnaire on clinical incidence in farms before and after using vaccination.Tables The vast majority of studies on all species showed positive reductions in all examined variables Figure , that inExcept for a few cases, vaccination in cattle was applied at early ages, in the first weeks of life, while in sheep more studies included adult sheep. The largest sample size studies, up to 150,000 animals, were done in cattle and preferentially recorded production effects in terms of paratuberculosis culling rates, since measurement of the other variables is much more time-consuming and costly. This is also reflected in the median sample size for the studies that looked at the production variable, 876, 700, and 4975 animals for cattle, sheep and goat studies, respectively, while studies analyzing the epidemiological or pathogenetic variables had median sizes around 100 or less.M. avium subsp. avium rather than MAP [9 CFU, and from 2.5 mg to 100 mg. The large majority of studies used some type of oily adjuvant  and in very few cases alum. In one study [The range of study length was between a few months and 16 years covering a period of 74 years. A large increase in sheep studies in the last decade coincided with the availability of the successful small ruminant commercial vaccine Gudair™ and its extended application in Australia and New Zealand. In the majority of the studies (68 experiments) killed vaccines were used. Most experiments used MAP strain 316F from Weybridge, nine used Strain 18 (now known to be than MAP ), and thne study , AquaVaxA wide variation in the efficacy of vaccines was observed, especially in cattle and sheep, where negative reductions are described in some studies. However, the overall results are pretty homogeneous, with very small error ranges due to the large numbers of observations included. In general, vaccine strain or administration route differences do not seem to substantially alter the outcome of vaccination, however, type of antigen formulation or adjuvant appears to have been important in a few experimental studies where different formulations were compared side by side .The goal of this review was to evaluate vaccination as a whole, summarizing the results into a single table for each type of measure used to determine vaccine success. This analysis has revealed that, in average, vaccination has a positive effect. However, since the efficacy figures are rather poor in comparison to vaccines for other microorganisms, it is relevant to at least try to discuss possible reasons for some of the low success rates. In order to simplify, one possible approach is to find an explanation for studies where vaccination performed below the average. Production effect studies where the measurement was total mortality may be considered flawed because in most cases mortality did not differentiate between paratuberculosis and other pathologies, possibly diluting the "vaccine effect". This is evident in the case of sheep and goat trials were adults were considered. Since the more sensitive part of the population might have already died of paratuberculosis before vaccination the remaining animals could be considered more resistant to paratuberculosis, and therefore, less likely to show any effect of vaccine protection. Because young animal studies showed larger effects, this becomes a very likely explanation for low reduction rates. An additional explanation for the poor results could be the fact that, frequently, vaccination programs coincide with the initiation of other control measures making it difficult to assess the real effect of the vaccine on paratuberculosis control.Under the epidemiological effects analyzed, reduction in the proportion of fecal shedders appears to be one of the measurements showing the widest variability. This happens mostly in small studies or in studies carried out in the Netherlands. Besides the qualitative effects in terms of protection conferred, vaccination should be assessed from another, perhaps even more important standpoint, such as is the reduction of amounts of bacteria shed by vaccinated and non-vaccinated animals.When considering reduction in pathogenetic effects, it should be pointed out that some of the studies had a very short follow up and that the presence of focal lesions of paratuberculosis are weighted the same as the presence of large areas of affected intestine.Since the vast majority of the studies show a positive effect, the question as to why vaccination has not been given more opportunities comes out with force. Especially, because for years MAP eradication efforts have only shown very moderate success or straight failure due to their enormous costs and frequent relapses of infected animals. Already in the eighties  and nineIn our opinion, there is a mixture of vested interests on control programs based in testing and culling, simplistic thinking comparing tuberculosis and paratuberculosis, fear of cross-reactions, academic detachment and confusion between ideal objectives and practical needs for the livestock industry. It is clear that the main reason for the opposition to MAP vaccination in cattle has been the problem of expected interference with the diagnosis of tuberculosis and its consequences in trade and national TB programs, however, the availability of an OIE official test -the comparative intradermal tuberculin test- that can very easily solve this problem in the majority of cases, should eliminate this concern on MAP vaccination in cattle. Recent field vaccination trials in cattle with an experimental MAP vaccine , have shown that less than 0.5% of vaccinated animals will give interference problems when the comparative intradermal tuberculin test is used even if the most restrictive interpretation of results proposed by the OIE is applied . The benefits obtained from production increases and reduction in clinical cases of MAP, will largely outweigh the small loss due to culling of these tuberculosis cross-reactive animals. In addition, new plans for the introduction of improved tuberculosis vaccines for cattle , will alMAP vaccination concerns in cattle have been further aggravated by the fear of the dairy industry to a crisis of confidence in their products, particularly, if a potential zoonotic link between paratuberculosis and a human disease (IBD/Crohn's disease) is confirmed  or if toParatuberculosis control poses a though challenge for farmers and veterinarians. Test and cull strategies can be useful in some settings but do not seem to have reached extensive success. Control by vaccination is an alternative that has been longtime in use in some regions and species. A substantial number of vaccination studies where objective information is amenable to meta-analysis treatment have been published in peer reviewed journals or in conference proceedings or other media. The high heterogeneity among reports makes it difficult to accept that the narrow statistical confidence interval obtained in these meta-analyses actually represents the true range of reduction in the whole set of trials. However, the results analyzed here clearly show a general positive effect from vaccination, negative effects only in a few trials, and a positive average balance according to all three variables considered . In terms of quantitative reduction, the minimum is an 11% reduction in MAP isolation, which could be considered the worst case average, but with a common outcome at over 50% which is highly profitable from a production point of view. This strategy thus has high chances of have a effect on the overall environmental contamination with MAP, which would mean a significant advance in the fight against paratuberculosis, both in the animal and in the  human public health fields.CC: Clinical Cases; CWC: Cell Wall Competent; CWD: Cell Wall Deficient; E: Experimental infection; F: Field trial; FC: Fecal culture; GL: Gross lesions; HL: Histological lesions; IBD: Inflammatory Bowel Disease; IF: Comparison of initial versus final prevalence; MAP: Mycobacterium avium subsp. paratuberculosis; MC: Comparison to matched controls; NCV: Non-commercial vaccine; NVH: Comparison to non-vaccinating herds; PCR: Polymerase Chain Reaction; PPDbov: Purified Protein Derivative from Mycobacterium bovis; PPDav: Purified Protein Derivative from Mycobacterium avium subsp. avium; P/O/P: Paraffin, Olive Oil, Pumice Stone Powder; Rec: Recombinant; TC: Tissue culture; TM: Total mortality, PCR: Polymerase Chain Reaction, MAP: Mycobacterium avium subsp. Paratuberculosis; IBD: Inflammatory Bowel Disease.®, a commercial paratuberculosis vaccine for use in sheep and goats.Felix Bastida works for Vacunek, a small animal health biotechnology company. He is currently working on the development of a new paratuberculosis vaccine for cattle in collaboration with NEIKER and CZ Veterinaria, the producer of GudairRamon A. Juste works for a Regional Government funded Agricultural Research Institute that receives funding for research projects from local, regional, national and European Governments, as well as, from companies such as CZ Veterinaria and Vacunek.RAJ conceived of the study and performed the statistical analysis. Both authors (FB and RAJ) participated in the design of the study, acquisition of data and helped to draft the manuscript. Both read and approved the final manuscript.


Region of Interest (ROI) extraction is a crucial step in an automatic finger vein recognition system. The aim of ROI extraction is to decide which part of the image is suitable for finger vein feature extraction. This paper proposes a finger vein ROI extraction method which is robust to finger displacement and rotation. First, we determine the middle line of the finger, which will be used to correct the image skew. Then, a sliding window is used to detect the phalangeal joints and further to ascertain the height of ROI. Last, for the corrective image with certain height, we will obtain the ROI by using the internal tangents of finger edges as the left and right boundary. The experimental results show that the proposed method can extract ROI more accurately and effectively compared with other methods, and thus improve the performance of finger vein identification system. Besides, to acquire the high quality finger vein image during the capture process, we propose eight criteria for finger vein capture from different aspects and these criteria should be helpful to some extent for finger vein capture. Consequently, there are It can be ascertained from From the above experimental results, we can see that our method has no obvious advantage. The main reason is that the number of skewed images in the database is limited and most images are normal. In order to further show the advantage of our method in dealing with skewed images, finger vein images of 50 fingers are picked to perform the above experiment again, in which most images are skewed. The experimental settings are the same as above. The experimental results are shown in 4.In order to increase the usability and stability of finger vein identification systems, lots of works have been done ,10–12, s(1)Suitable and stable illumination. The illumination intensity of the capture device has a significant impact on the quality of captured finger vein images. If the illumination intensity is very low, there will be lots of noise in the captured images, which will increase the difficulty of the follow-up processing. If the illumination intensity is very high, thin vein patterns will be lost. As we known, the near-infrared light with 700 nm–1,000 nm wavelength is best for capturing finger vein images, so near-infrared light with suitable intensity and light emitting diodes with stability performance are essential.(2)Healthy and clean fingers. The finger of the subject which is used to capture finger vein images, should keep clean. Lots of factors will affect the penetration ability of near-infrared light, for example, moles, tumors and scars on the finger skin surface. When capturing finger vein images, we should choose healthy fingers without moles, tumors, scars or finger rings.(3)The light transmission technique. There are two methods to grab the vein pattern: the light transmission technique and the light reflection technique . In the (4)Correct finger position. The more finger vein patterns are extracted, the better identification performance will be achieved. When capturing images, fingers should be placed in the proper position, so that the distal inter-phalangeal joint, proximal inter-phalangeal joint and middle phalanx between the two joints are all in the captured finger vein image.(5)Non-invasive and contactless data capture. As finger vein patterns are internal features and the near-infrared light penetrated the finger to capture finger vein imaged, the capture device should be designed to be user friendly and touchless. Non-invasive and contactless data capture ensures both convenience and cleanliness for the users, and it is more acceptable for the users.(6)Feasible capturing environment. The captured finger vein image contains veins that have various widths and brightness, which may change with fluctuations in the amount of blood in vein, caused by changes in temperature ,15. For (7)Capturing images in different sessions. This mainly refers to the fact that the registered samples in the database should be captured in different sessions, and the interval between different sessions is two weeks at least or a longer time.(8)Limited finger movement. In order to simulate the randomness of finger placement in image capture, when we capture the registered samples, we require the subject to rotate and move the captured finger. This action also can lead to negative effects: (a) if the position offset of the finger is very big, local vein information will be lost; (b) the random rotation and movement of finger may cause finger skew; (c) The phenomenon that the locations of the same section of a finger vary in different images of the finger, will appear. For (b) and (c), we can design a robust preprocessing algorithm to solve these issues, but for (a) the lost finger vein patterns are irretrievable. Therefore, it would be best to avoid big finger position offset and tilted fingerd in random finger movements.Influenced by many factors, there are a certain amount of low quality finger vein images. Fortunately, the quality evaluation of finger vein images has been researched . ThroughIn short, the high quality finger vein image is the basis of the good performance of finger vein identification system. Under these criteria, we can improve the quality of captured finger vein images, which is helpful for preprocessing, feature extraction and matching.5.In this paper, we present a robust ROI extraction method. We first detect and correct the image skew, then we make use of the phalangeal joints to ascertain the height of the ROI, and lastly we regard two internal tangents of the finger's edges as the left and right edge of the ROI. Two strengths of our method are the skewed image detection and correction and the definition of the ROI's height using a sliding window, which can overcome mismatching due to finger displacement. Compared with other ROI extraction methods, the proposed method works more accurately and effectively and leads to higher accurate performance, as shown from the experimental results. Besides, we present eight criteria for finger vein capture which will prove helpful to some extent for finger vein capture.Through our deep observation of the finger vein image, we find a phenomenon that the phalangeal joint may not always located in the row with the higher gray value in the finger vein image. We guess the reason is the uneven illumination. In the future, we will explore the factors which cause this phenomenon.


In 2005, a survey was conducted among all the 27 high schools of Aden, which revealed low levels of knowledge on major prevention measures, and a high level of stigma and discrimination towards people living with HIV (PLWH). The results served as a baseline for implementing a school-based peer education intervention for HIV prevention in the 27 schools of Aden. In 2008, and after 3 years of implementation, a quasi-experimental evaluation was conducted, which revealed that the peer education intervention has succeeded in improving HIV knowledge and skills; and in decreasing stigmatization of PLWH. This process evaluation aims to give a deeper understanding of the quasi-experimental evaluation which was conducted in the 27 high schools of Aden, and to highlight the factors that facilitated or inhibited school peer education in such a conservative Muslim setting. Qualitative methodologies were pursued, where 12 focus group discussions and 12 in-depth interviews were conducted with peer educators, targeted students, school principals, social workers, and parents of peer educators. Results revealed that school-peer education was well received. There was an apparent positive effect on the life skills of peer educators, but the intervention had a lesser effect on targeted students. Key enabling factors have been the high quality of training for peer educators, supportive school principals, and acceptance of the intervention by parents. These findings are important for improving the life skills and peer education intervention at the school level, and in better planning and implementation of life skills and peer programmes at a national scale. The Republic of Yemen is located in the southern part of the Arabian Peninsula and is surrounded by Oman to the east, Saudi Arabia to the north, the Red Sea to the west, and the Arabian Sea and the Gulf of Aden to the south. Yemen is the poorest country in the Middle East and one of the poorest countries in the world , where mEpidemiologically, the HIV prevalence among the general population of Yemen, including youth is 0.2% . HoweverAden, a governorate in the Republic of Yemen, located on the Arabian Sea, with close proximity to the Horn of Africa, is especially at risk of HIV infection. Previous studies have revealed that several risk factors exist in Aden, which include the presence of commercial sex work, male-to-male sex, and population movements to and from countries with high HIV prevalence .In March-May 2005, a survey among Yemeni high school students in Aden revealed that only 49.4% recognized the protective role of condoms . Stigma and discrimination levels were high among students. Around 40% of the suggested actions by students on how to deal with people living with HIV (PLWH) were punishment actions, which included suggestions for killing PLWH. The results from this study convinced the education authorities in Aden, Yemen, to implement a school-based peer education programme for HIV prevention, which focused on decreasing the level of stigma and discrimination towards PLWH and on increasing the knowledge about modes of HIV transmission and prevention , and becIn 2008, the evaluation of the school-based peer education intervention was conducted , representing all existing high schools were the site of the intervention. The intervention included training of school coordinators, selection and training of peer educators, training of school management teams, and implementation at school level  conducted by two international Arabic speaking experts in the field of training of trainers on youth reproductive health, HIV prevention, life skills, and peer education, and the training package was based on a Jordanian life skills and peer education package supported by UNICEF Middle East and North Africa Regional Office . The traPeer educators from all 27 high schools were recruited on a voluntary basis. Among those students who volunteered, a few were selected who met the standard criteria of having good communication skills, being accepted by classmates, and had good academic achievement. The selection was done by a committee consisting of the school coordinators and school social workers. The school coordinators visited parents of selected peer educators to explain the programme and to obtain a signed consent form allowing their daughters/sons to participate. Several visits were required, especially for parents of female peer educators, as families were reluctant to have their daughters get involved in extra-curricular activities, and especially as these related to HIV and AIDS prevention. The school coordinators team had a pivotal role in advocating with families. In case of refusal by parents, another peer educator was selected. Parents' refusals only occurred in the first year (2005); from the 30 peer educators selected, three parents refused to allow their children to participate, leaving 27 students who were trained as peer educators. In the following years, there were no parental refusals. So, during the 3 years of programme implementation (2005–2008) only three refusals were faced among 140 selected peer educators, leaving 137 peer educators who participated in the programme  approach; the seventh was on major misconceptions; the eighth was on risk perception and whether young people can be at risk; the ninth was on how one should deal with PLWH, which stresses the importance of the right of PLWH to live free of stigma and discrimination; and the tenth message was on the role of young people in educating the community. The life skills messages were on communication and negotiation skills, self-awareness and self-esteem, decision making, respecting differences in opinions, and assertive behaviour (The peer educators were trained in a 10-day (8 h/day) workshop. The training was based on the Jordanian life skills and peer education package, and peer educators were trained in providing 10 messages on HIV transmission, prevention, and common misconceptions, and 5 life skills messages. HIV messages involved the following: the first message was on the definition of HIV and causative agent; the second on whether one can recognize an infected HIV person by the way he/she looks or whether a blood test is needed, and what the window period means; the third message was on why HIV is a dangerous infection; the fourth message was on the epidemiology of HIV in Yemen, the Middle East, and in the world; the fifth was on the mode of transmission; the sixth was on modes of prevention and adopting the ABCD  training workshop on peer education methodologies, life skills, and HIV prevention. School coordinators planned the peer activities at their schools with peer educators and management teams  were the major topics covered by peer educators. Peer educators conducted educational sessions as an extra-curricular activity once a week for 90 min in a class room setting. Peer education sessions were planned in a way that each student would receive two (90 min) sessions in addition to brief sessions during morning school broadcast  and in conducting in-depth interviews (IDIs) with young people. The training workshop for qualitative data collectors provided them with the research skill they needed, and also resulted in refining the questions to be asked.Multiple instruments were used to collect process data, while ensuring that all 27 schools were represented by the participants. Participants included 54 male and female peer educators, 32 male and female students who participated in the programme, 4 school principals, 4 school social workers, and 4 parents. Instruments included 12 FGD and 12 IDI.The objectives of the 8 FGDs with the 54 peer educators were to evaluate the programme from their perspective, study the effect of life skills on their life and the life of their peers, and come up with recommendations to improve the intervention. The objectives of the 4 FGDs with the 32 students was to evaluate the methodology of peer education from the perspective of the targeted students in relation to: frequency, timing/length/place of sessions, participatory/interactive approach, and space of classroom; and whether an enabling environment existed: space, number of students per sessions, place . In the focus groups with students recommendations to improve upcoming programmes were also asked. The objectives of the 4 IDIs with social workers and the 4 IDIs with school principals were to explore their overall opinions on the programme, to know their role in the programme implementation, and to come up with suggestions for improvements, scaling up, and sustainability of the programme. In regard to the 4 IDIs with parents, the objective was to assess their acceptance of the peer education intervention, and to learn their perception of the effects of peer education on their children and how they estimated the impact of the peer education on the students' relationship with his/her family and on their other social relations .IDIs (12) and FGD  were facilitated by nine data collectors , who were trained in a 4-day workshop. All FGDs and IDIs were conducted during February 2009. FGDs and IDIs were conducted over two consecutive sessions, with a 10 min break in-between, where refreshments were served, and casual discussions were stimulated by data collectors to further build trust with participants. All interviews and FGDs were tape-recorded and then fully transcribed. The transcripts were translated into English, and analysed line by line and coded thematically.Some quantitative results were used from the quasi-experimental evaluation, which included a random sample of 2510 students from the 27 high schools. These are mainly related to the following measure:Receiving peer education and whether students think its beneficial: whether a student was targeted by the intervention or not was assessed by a closed question on whether the student had ever attended or heard of AIDS education by peers in his/her school; yes/no options were available. Those answering yes were moved to the next closed question on whether they considered peer education in schools beneficial, with the following options: beneficial; beneficial to some extent; not beneficial.Written consent for the study was obtained from the Director General of the Education Office in Aden. Verbal consent was obtained from all study participants. Issues related to consent seeking  were all addressed prior to initiation of FGDs and IDIs. In addition, the Ethics Committee of the Faculty of Medicine and Health Science, Sana'a University, granted the ethical approval to conduct this study.The themes emerging from the analysis of the FGDs and IDIs were grouped into the following categories:Students’ experiences of the interventionAcceptance of the programme by parentsThe intervention as viewed by school principals and school social workersEffect of life skills on peer educators and studentsAddressing high-risk behaviour and condoms in classroom settingAddressing high-risk behaviour and condoms out of classroom settingDifficulties faced during implementationThe results from the quantitative study  revealed that among 78.6% (1964/2498) of the students who stated that they had received peer education in schools, 76.6% (1505/1964) considered it as beneficial and 21.7% (426/1964) considered it as beneficial to some extent. Only 1.7% (33/1964) of the students considered peer education as not beneficial Targeted students repeatedly mentioned the important role that peer educators played in the intervention. Most of the discussion was on how well the peer educators were trained, which affected positively the comprehension of messages:The peer educators are well trained and have good communication methods to communicate information to us. Peer educators were also well received by targeted students because of their positive and pleasant attitude, and their patience in answering questions:The peer educators are friendly, hard workers, energetic, patient, knowledgeable about AIDS, and never get tired of our questions. Peer educators had also a key role in stimulating participation of targeted students at classroom level:The proof that the sessions are interactive is that those students who are usually sleepy in the routine classes become active in the education session. Even, hesitated and very quiet students become active and participate in a good way. All parents mentioned that their written consent for their children to participate in the peer education activities was asked by the programme coordinator from the Aden education office. They explained that their major concern was the effect of the programme on learning achievements. The school coordinators team has played a key role in advocating with parents to agree on their children's participation in the programme. As one mother reported:I agreed after extensive discussion with school administration and their strict confirmation that this activity will not interfere with my son's study.School principals had also indicated that effective communication with parents resulted in acceptance of the programme:We gained the trust of parents and families. All parents highly appreciated the positive effect of the peer education intervention on their children. However, they indicated that they would prefer future interventions to be conducted during summer vacation, so academic achievement would not be affected.School principals and social workers indicated that the peer education interventions had a positive impact on peer educators, students, social workers, and teachers.This is the best programme I had ever known although I had participated in many training courses. The programme is good in everything, starting from the idea to the trainers and the selected peer educators. Both school principals and school social workers were trained as part of the intervention on HIV prevention, youth participation, peer education, and life skills education. They did not take part in the actual delivery at the classroom level, but facilitated the implementation. School principals were the contact focal points between the school and the project coordinator, who was also part of the school coordinators committee and was a senior advisor to the director general of the education office in Aden. School social workers described their role in selecting peer educators to be trained, and selecting students to receive the peer education sessions:Everything in the programme is good: the idea itself, its good consequences in raising the awareness not only for students but the community as well and its possession of all elements of success. The peer education methodology was also accepted by school principals and social workers:The idea of having educators from the same age and educational level of student is great because they are more likely to be open with each other. Life skills education was a unanimously mentioned factor leading to the success of the interventions. They suggested that peer education and the life skills interventions should be started as early as seventh grade. They believed that life skills education is a successful methodology to decrease risky behaviours among adolescents.The school-based intervention had a clear effect on the life skills of peer educators, mainly, communication skills, assertive behaviour skills, decision making, self-esteem, and self-efficacy. This effect was repeatedly reported by peer educators and parents of peer educators.Peer educators discussed passionately what impact life skills training had on them. They reported that life skills had positively influenced their attitude towards others and their role in life:Learned to be more responsible, faithful, patient, flexible, good listener, respect other's opinion, able to negotiate with older and younger people. Major comments of parents of peer educators' on the intervention were on how their children's life skills had changed dramatically. They mainly mentioned life skills related to communication, negotiation, accepting other opinions, and self confidence:They became, self-confident, and decisions makers for themselves. (A peer educator's parent)School principals also acknowledge the important effect the intervention had on building life skills of peer educators:Trained peer educators are self confident, broad minded, good communicators not only for AIDS education but also in many life aspects. There was a consensus among students about the importance of the programme with regard to improving their knowledge on HIV prevention and transmission and attitudes towards PLWH; however, changes in life skills were less frequently mentioned:The education helped me a lot to be assertive in my behaviour, to be proud with who I am, and to express myself very well. Discussing male-to-male sex as a high-risk behaviour was a sensitive topic to discuss at classroom level, as one peer educator said:I approach homosexuality only superficially because it is a very difficult and sensitive issue. Female peer educators were more reluctant to discuss male-to-male sex as a risk behaviour relative to male peer educators.Male peer educators were more open to discuss the use of condoms than female peer educators. Female peer educators repeatedly reported that they were intimidated by the questions raised on condoms:Girls made me embarrassed by their questions about condoms. Peer educators reported that it was much easier for them to discuss high-risk behaviour and condom use with their peers out of the school setting. They thought that they succeeded in some cases in educating their peers to adapt less-risky behaviour, and had little effect in other cases:Some of my friends said they are now using condom to protect themselves; and some are asking me where they can get tested for HIV. We approached several girls with high-risk behaviours and explained the ways of HIV transmission and prevention. Some quitted such relations, some are now relying on condoms, while others continue practicing unprotected sex. Peer educators indicated also that there were some rare nonsexual high-risk behaviours, such as sharing the glass for body carving, where girls carve the name of their boyfriends on their hands with a sharp glass. Female peer educators reported that although some of their peers stopped such practices, others continued. Overall, peer educators discussed the use of condoms with much more ease than discussing male-to-male sex, which is even a harder topic to tackle among female peer educators.Several constraints faced peer education in the classroom setting. Time was mentioned as a major constraint by both peer educators and targeted students. They all stated that more time should be given to the sessions as many questions remained unanswered after the session ended. Other constraints mentioned were the shortage of screens to display slides and the non-availability of printed material on HIV and life skills.This process evaluation aimed to highlight the factors that facilitated or inhibited the peer education intervention in the 27 schools of Aden, and to provide a deeper understanding of the quasi-experimental study outcomes, which revealed that the school-based peer education intervention succeeded in improving knowledge on HIV transmission and prevention and in improving attitudes towards PLWH , but also others of relevance in the peer's environment (out-of-school peers) through an informal (passive) diffusion.The high acceptance of the intervention by parents was mainly due to the key role of the school coordinators and the project coordinator in advocating with families. Interestingly, the main concern was not educating on HIV prevention, but rather the potential adverse effect on scholastic achievement as perceived by parents. This is an important finding, as the school-based peer education has been labelled by the Education Office in Aden as life skills and peer education programme rather than a sex education programme. Labelling as a ‘sex education’ programme might have doomed the failure of peer education intervention in the context of Yemeni schools. This ‘life skills’ label of the intervention was also the sentiment which came forward from interviews with school principals and social workers. The capacity building opportunities with training and advocacy workshops of school principals and school social workers had created an enabling environment for the intervention. Their high acceptance of the peer intervention has facilitated implementation at the classroom level as well as acceptance from families. School coordinators, who have acted as resource persons for hard-to-answer questions at classroom level, had contributed to the success of the implementation. This is in line with existing research, which documents the important role of adult support in school-based peer education .There is existing research, which has studied the implementation of HIV education in schools, mainly through process evaluation . All of The fact that the majority of students considered peer education sessions beneficial and had appreciated the participatory nature of the sessions reflects the important role of peer educators in the successful implementation of peer education sessions at the classroom level. It also emphasizes the fidelity of the programme. Previous research has also shown that peer-led school-based interventions were more effective when they were participative and skills-based .The FGDs had provided a more in-depth understanding of the quasi-experimental study (The difficulties faced during implementation at the classroom level which are mainly related to time and provision of necessary visual display material are two issues that will have to be tackled if peer education and life skills are to be taken to scale in Yemen. Visual display materials would not be available in the majority of Yemeni schools, due to poor funding. For this reason, peer educators have to be trained on using existing posters. The time allocated for the sessions and the frequency of the sessions are real hindering factors in any school-based peer education intervention , and thuThe present process evaluation has some limitations. The first limitation concerns the fact that it was conducted after the impact evaluation, so there is an inherent bias on the results of the FGDs and IDI .It is recommended that life skills education is integrated within the Yemeni school curriculum in the long term and as an extra-curricular activity in the short term. The life skills and peer education training package could be used as a national training manual among in and out-of-schools young people. Several researchers might disagree with this recommendation as many studies have shown that there is no significant direct relation between acquiring life skills education and decreasing high-risk behaviour or a decrease in seroprevalence of HIV . HoweverThis process evaluation, which was theoretically based on the Diffusion of Innovation Theory , has rev