Many efficacious health service interventions to improve diabetes care are known. However, there is little evidence on whether such interventions are effective while delivered in real-world resource-constrained settings.To evaluate an intervention aimed at improving diabetes care using the RE-AIM  framework.n=163 diabetes patients) and the four matched facilities served as control (n=154). The intervention included provision of culturally appropriate education to diabetes patients, use of generic medications, and standard treatment guidelines for diabetes management. Patients were surveyed before and after the 6-month intervention period. We did field observations and interviews with the doctors at the intervention facilities. Quantitative data were used to assess the reach of the intervention and its effectiveness on patients’ knowledge, practice, healthcare expenditure, and glycemic control through a difference-in-differences analysis. Qualitative data were analyzed thematically to understand adoption, implementation, and maintenance of the intervention.A quasi-experimental study was conducted in a poor urban neighborhood in South India. Four health facilities delivered the intervention (Reach: Of those who visited intervention facilities, 52.3% were exposed to the education component and only 7.2% were prescribed generic medications. The doctors rarely used the standard treatment guidelines for diabetes management. Effectiveness: The intervention did not have a statistically and clinically significant impact on the knowledge, healthcare expenditure, or glycemic control of the patients, with marginal reduction in their practice score. Adoption: All the facilities adopted the education component, while all but one facility adopted the prescription of generic medications. Implementation: There was poor implementation of the intervention, particularly with regard to the use of generic medications and the standard treatment guidelines. Doctors’ concerns about the efficacy, quality, availability, and acceptability by patients of generic medications explained limited prescriptions of generic medications. The patients’ perception that ailments should be treated through medications limited the use of non-medical management by the doctors in early stages of diabetes. The other reason for the limited use of the standard treatment guidelines was that these doctors mainly provided follow-up care to patients who were previously put on a given treatment plan by specialists. Maintenance: The intervention facilities continued using posters and television monitors for health education after the intervention period. The use of generic medications and standard treatment guidelines for diabetes management remained very limited.Implementing efficacious health service intervention in a real-world resource-constrained setting is challenging and may not prove effective in improving patient outcomes. Interventions need to consider patients’ and healthcare providers’ experiences and perceptions and how macro-level policies translate into practice within local health systems. India is a home to over 68.8 million people with diabetes, a majority of whom struggle to get quality healthcare . The neeSystematic reviews of randomized controlled trials showed that these suggested interventions are likely to be efficacious. Health education to diabetes patients has been shown to improve patients’ knowledge and glycemic control –15. InteThere is, however, a dearth of studies on the application of these interventions in real-world settings, especially in the local health systems of low- and middle-income countries. Sanders and Haines  emphasizThe Institutional Ethics Committee at the Institute of Public Health (India), the Institutional Review Board at the Institute of Tropical Medicine (Belgium) and the Ethics Committee at the University of Antwerp (Belgium) approved this study. The study was explained to the diabetes patients before informed written consent was sought, separately for the surveys and blood sugar tests. The study was explained to the doctors at the intervention health facilities before informed written consent was sought, separately for being part of the study (and agreeing to implement the intervention) and for the interviews at the end of the intervention.We conducted the study in Kadugondanahalli , one of the administrative units of Bangalore. Bangalore is a metropolitan city, capital of the southern Indian state of Karnataka. KG Halli is a poor neighborhood housing a slum and a population of around 45,000 in an area of less than one square kilometer. It has two government health centers, one providing limited primary care and the other providing primary care and some specialist care. It has over 32 private health facilities: Four are hospitals providing primary, specialist, and inpatient care, while the rest are single-doctor clinics providing primary care on an outpatient basis. Private facilities provide care on a fee-for-service basis. Government centers provide free care for the people living in below-the-poverty-line households and charge nominal fees to other patients. For more details on chronic conditions and health system organization in KG Halli, please refer to our earlier work –25.We conducted a quasi-experimental study with an intervention and a control group. The Institute of Public Health  has been implementing the Urban Health Action Research Project in KG Halli since 2009 with an aim to improve the quality of healthcare for its residents by working with residents, the healthcare providers, and the health authorities. As part of this project, six rounds of dialogue with local healthcare providers were organized between August 2011 and March 2012 to discuss residents’ health issues, including chronic conditions and the potential solutions –10. Subsintervention sites and the doctors delivering care at these facilities as intervention doctors. Next, four control health facilities similar to the intervention sites in terms of type of clinic/hospital, level of formal training of doctors, and the usual load of diabetes patients seeking care from these facilities were matched. Based on willingness of the doctors to adopt the intervention in their routine practice, we conveniently sampled seven health facilities  from KG Halli and assigned them to the intervention group. The government facility had a mandate to provide free care and as such no control facility could be matched. Two of the six private facilities were technically unable to implement certain aspects of the intervention and were excluded. Hereafter, we will refer to the remaining four facilities as When estimating the minimum sample size for the study, we expected certain improvements in the effectiveness measures. These primary measures and the change expected in them included the following: 1) a two-point increase in the patient knowledge score (range 0–15); 2) a five-point decrease in the mean blood sugar level; and 3) a 50% reduction in the mean out-of-pocket expenditure. Considering a significance level of 0.05, 80% power, and average values of patient knowledge score, random blood sugar, and out-of-pocket expenditure from earlier studies , 26–28, We sampled these patients with help from community health workers as part of the Urban Health Action Research Project. These health workers were women from KG Halli and surrounding neighborhoods with a socioeconomic background similar to that of the people in KG Halli. They had been working in KG Halli for around 4 years making routine visits to households in their respective areas. They approached diabetes patients at their residence. People between the ages of 15 and 64 years, residing within KG Halli, with self-reported diabetes mellitus type 2, and who sought care from one of the intervention or control sites at least once in the last 3 months were considered eligible for the study. Severely ill or mentally incompetent patients were excluded.The data collection tools included a survey of diabetes patients (before and after the intervention), interviews with the intervention doctors at the end of the intervention, and field observations by the first author throughout the intervention, including 3 months past the intervention.Supplementary File 1 for a copy of the questionnaire (in English) that sought data about sociodemography, health-seeking, exposure to posters/videos, treatment details, healthcare expenditure, knowledge, and practice in regard to diabetes and perceived social support. The community health workers administered a questionnaire to the sampled patients in a language  that patients were comfortable with. The community health workers carried out a blood sugar test using a blood glucose monitoring device at the patients’ residence after an overnight fast by the patients. The health workers were trained in questionnaire administration as well as the use of the glucose monitoring device. The same questionnaire and the glucose monitoring technique were used for the initial survey and a follow-up survey after the 6-month intervention period. A trained data entry officer entered the data using EpiData Entry (EpiData Association 3.1). We used STATA (StataCorp LP 11.2) to do difference-in-differences analysis to ascertain the effectiveness of the intervention on the knowledge, self-management practices, out-of-pocket healthcare expenditure, and fasting blood sugar of the patients . Audio-recorded interviews that lasted 45 to 60 min were conducted in a mix of English and Hindi. Open-ended questions were followed with more specific probes to clarify and extend the responses. Records were transcribed verbatim and translated into English by a professional transcriptionist. The first author verified the transcripts based on audio records. Transcripts were analyzed by using thematic content analysis to identify emerging themes. Data were organized and coded using NVivo software  and later the relationship between and across themes was explored using the mind-mapping tool MindNode Lite (IdeasOnCanvas GmbH 1.9.1). Data from the post-intervention survey (about reach of the intervention) and field observations were used for triangulation.At the end of the intervention period, the first author, with formal training in qualitative research, conducted interviews with the four intervention doctors to understand their experience and views with regard to implementation of the intervention, adaptations that they made to the initial intervention, impact of the intervention on patients, and sustainability of the intervention. The doctors were the respondents of choice, as they owned and managed the intervention sites while also providing healthcare to diabetes patients. A semi-structured questioning guide was developed, pretested, and refined (see Supplementary File 2). Immediately after the visit, observations and the discussion were recorded in an online field diary, Evernote (Evernote Corporation 2.0.5). These data were analyzed in the same way as the interviews to understand implementation, adoption, and sustainability aspects of the intervention.The first author made follow-up visits to the intervention doctors once a month to discuss the status of the implementation of the intervention and gather their feedback. He made observations about the implementation of the intervention  as well as about the reactions of the patients and health workers. He used a structured observation grid and pointers for discussion with the doctors  and those from the control group who had no exposure to the videos and/or posters about diabetes (n=69). The size of these groups was smaller than the minimum sample size estimated for the study, compromising the power to detect the expected impact. We did not assess the effectiveness of the generic medication and STG components, as only eight patients had received generic medications in the intervention group and the intervention doctors rarely used STG for diabetes management. The unadjusted difference-in-differences analysis showed that after the intervention the mean knowledge score improved marginally (+0.23) while the mean out-of-pocket expenditure decreased (−29.21). The mean practice score deteriorated marginally (−0.48) and the mean fasting blood sugar level increased (+3.83). These changes were statistically insignificant. After adjusting for sociodemographic and disease-related covariates, the direction of change in effectiveness measures and its statistical insignificance remained same, except that the marginal reduction in the mean practice score (−0.85) became statistically significant  showed willingness to experiment with the intervention, but they could not be part of the study for the reasons cited earlier in methods section.The implementation of the intervention varied across intervention sites as well as across the different components of the intervention.This component was the most widely implemented; posters and videos were displayed at conspicuous places at all the four sites. One of the sites preferred the installation of the television monitor inside the consultation room, unlike the other three sites, which installed it in the patient waiting areas. This decision was mainly due to the doctor's concern about the safety/security of the monitor, as the doctor worked alone at that facility with no support staff manning the patient waiting area. This change also meant that at this site the intervention was delivered individually and selectively to diabetes patients as part of the consultation process. The researcher's field observations indicated that three of the intervention sites routinely displayed videos during peak consultation hours. However, one of the sites hardly switched the monitor on. It was a busy site, and the responsibility for operating the monitor was vaguely allocated between receptionist and pharmacist with no supervision, leading to almost no use of the monitor during the intervention period. One of the doctors, at the request of some of his patients, provided copies of the video files to the patients.Three of the videos were marginally edited during the early intervention period when one intervention doctor pointed out that patients were curious about those films referring to data from another country instead of India. Similarly, a poster on dietary information was slightly modified at the request of one the doctors, as there was a mention of pork meat, which could have hurt the sentiments of Muslim patients.During the intervention period, only eight patients received prescriptions of generic medications. The following themes that emerged from interviews with the doctors explain this poor implementation.We are not getting 100% efficacy [with generic medications]. Patients are taking three to four tablets and still their sugar levels remains high, in spite of the diet, physical exercise, and patients’ mental status. The moment we change [to brand-name] medications, we get improvement. Prescription of brand-name medications containing a combination of drug compounds (as opposed to single-compound generics) seems to be a norm, not just for diabetes but also for most other ailments. One of the doctors claimed that the patients in the area have either become ‘resistant’ to single-compound drugs  or have become ‘used to’ combination drugs.See, most of the single [compound] drugs are not working, be it antibiotic or pain killer …. We have to give combinations. When probed about the safety of such a practice, the doctor confided that the safety of such medications has not been ascertained and it could be problematic in the long term. However, the notions that combination drugs give faster results and the primacy accorded to meeting patients’ expectations, at the expense of available scientific knowledge in a competitive commercial healthcare sector, seem to drive this practice. Doctors often doubted the quality of generic medications.While some generics are good and efficacious, many are produced in small places, like a small house, and are of poor quality. Two of the doctors expressed their doubts about the efficacy of generic medications. They believed that generic medications often come with less strength or lower amounts of the base ingredient compared to what is specified on their packaging. Their concerns were rooted in their past experiences and personal assessments of the use of generic medications.They cannot take five or six tablets daily. For hypertension, they have to take one tablet. Automatically cholesterol will be there and other problems will be there. Generic medications are available as single-drug compounds. Diabetes patients, who often suffered from other morbidities and who were routinely prescribed fewer brand-name medications containing a combination of drug compounds, had to take multiple generic medications.We have a migrating crowd. That is why I don't prefer to use generic medicines, specifically in diabetes and in hypertension kind of prolonged illnesses. Considering that a part of the population in KG Halli and the surrounding neighborhoods tend to migrate and keep shifting their residence, the lack of universal availability of generic medications was another concern.The doctors at the intervention sites reported a very limited use of STG in their practice. Two major themes defined poor use of STG.See, 50% (of diabetes management) is by the doctor and 50% is by patients. But once patients come, it becomes [the] responsibility of doctors to treat them, whether they take care of themselves or not. That's where we are facing the problem. Doctors were expected to be primarily responsible for treating the ailments and treatment was seen as prescription of medications and/or some active intervention. This understanding implies that the doctors found it difficult to promote the active role of patients and the use of non-medical avenues (e.g. self-management practices) in diabetes management.The guidelines could be fully practiced if the patient is being newly diagnosed as diabetic. Eighty percent of my patients are already diagnosed with diabetes and I am just following them. The other factor that constrained doctors from using the STG was that they rarely diagnosed new cases of diabetes. They generally did follow-up consultations with patients, who were often diagnosed and put on a given treatment plan by specialists.The field observations, made for 3 months post-intervention, confirmed the ongoing use of posters and television monitors for health education at the intervention sites. The use of generic medications and STG for diabetes management remained very limited, as was the case during the intervention period.We found the RE-AIM framework useful in assessing the intervention in its different dimensions and relevant from a public health viewpoint. The health service intervention – aimed at promoting culturally appropriate health education, generic medications, and STG for diabetes management – reached a very limited number of patients, especially with regard to use of generic medications and STG for diabetes management. It did not have a statistically and clinically significant impact on the knowledge, out-of-pocket healthcare expenditure, or glycemic control of patients with an  reduction in their mean practice score. The absence of any impact can be explained by poor implementation of the intervention, reflecting non-acceptance and/or lack of willingness of doctors to change at the intervention sites. Doctors’ concerns about the efficacy, quality, availability, and acceptability by patients of generic medications explained the limited prescriptions of generic medications. The patients’ perception that ailments should be treated through medications limited the use of non-medical management by the doctors for the early stages of diabetes. The other reason for the limited use of the standard treatment guidelines was that these doctors mainly provided follow-up care to patients who were previously put on a given treatment plan by specialists. Positively, the doctors perceived that the culturally relevant education delivered in local languages and videos generated curiosity among patients, who felt more confident in asking questions, leading to enhanced knowledge and self-management practices.We identified the reasons why the intervention, which was delivered in a real-world, resource-constrained setting, was not found to be effective. First, merely making low-cost generic medications available was not sufficient to reduce treatment cost for patients. The doctors’ perceived low efficacy and availability as well as acceptability by patients of generic medications were reasons for their poor use. Concern about the quality of generic medications is widespread among doctors beyond KG Halli and to some extent seems justified. Ravinetto et al.  highlighThe very limited use of STG for diabetes management was explained by the fear of medical doctors that lack of prescription is perceived as lack of treatment by the patients. Studies from Australia  and the The limited role of the primary care doctors in deciding the treatment plan for diabetes patients was another reason for poor use of STG. This highlights the fragmentation of healthcare services, with poor referral links across the types and levels of healthcare services in India. This situation makes it difficult to coordinate and ensure continuity in patients’ care. Our earlier analysis  of the lOur study has limitations. Due to limited resources, we opted for a shorter intervention period of 6 months. A longer intervention duration would have helped overcome some of the implementation challenges identified during the course of the intervention. Our study also suffered from high crossover and contamination, where many patients either visited sites other than the study sites or they visited both the intervention and control sites, reducing the uncontaminated sample beyond the minimum sample size needed to detect the predicted change in outcome variables. Although we envisaged and accounted for this in the sample size calculation, the extent of contamination was greater than we expected. The use of the RE-AIM framework, however, helped us to understand other important dimensions of the intervention, beyond the effectiveness, including the reasons for poor implementation. Our findings provide valuable insights to public health authorities about some of the challenges and opportunities for reforming healthcare services to improve care for diabetes and other chronic conditions, especially in harnessing the huge private health sector in India , 41.This health service intervention – aimed at promoting culturally appropriate health education, generic medications, and STG for diabetes management – reached a very limited number of patients. It did not have statistically or clinically significant impact on the knowledge, out-of-pocket healthcare expenditure, or glycemic control of patients with an  reduction in their mean practice score. The doctors, however, perceived that the culturally relevant education delivered in local languages and the videos generated curiosity among patients, who felt more confident in asking questions leading to enhanced knowledge and self-management practices. Implementing an efficacious health service intervention in a real-world resource-constrained setting is challenging and may not prove effective in improving patient outcomes. Interventions need to consider patients’ and healthcare providers’ experiences and perceptions and how macro-level policies translate into practice within local health systems.Click here for additional data file.Click here for additional data file.


A rigorous cross-cultural adaptation process of an existing instrument could be the best option for measuring health in different cultures, instead of developing a new tool, and prior to psychometric and validation testing. The Dental Discomfort Questionnaire (DDQ), a validated instrument for assessing toothache in young children, has not been cross-culturally adapted so far. This study aimed to explore the detailed phases of the cross-cultural adaptation process of a pain assessment tool, presenting the example of the DDQ Brazilian-Portuguese adapted version.The study design was based on the universalist approach, which consists of a sequential analysis to assess the relevant phases of a cross-cultural process before testing the measures of the instrument: conceptual, item, semantic, and operational equivalences. Systematic information was gathered from the literature, expert discussions, translations, and pre-testing through cognitive interviews with Brazilian population.Detailed description of the three major phases for a cross-cultural adaptation process was given. Notes of the changes done in the structure of the presented instrument (DDQ) were specifically pointed out at each phase. Conceptual and item analyses showed that there are similarities in the DDQ construct between the original and Brazilian cultures that require minor modifications. Translations and back-translations allowed the development of the preliminary Brazilian-Portuguese version of the DDQ, which was tested and underwent other minor changes to improve its comprehensibility.Describing the phases was important to show how changes are made in a cross-cultural adaptation process of an instrument. This also could help researchers in adapting similar pediatric pain assessment tools to different cultures. A Brazilian-Portuguese version of the DDQ was presented.The online version of this article (doi:10.1186/1756-0500-7-897) contains supplementary material, which is available to authorized users. Pain is a common experience in children starting in infancy . Part ofAlthough self-report is considered to be the gold standard for assessing pain , immaturThe English-language version of the DDQ has been used in several studies in the literature –13, but This study aimed to present the detailed cross-cultural adaptation process of a pain assessment tool across two different cultures and languages, based on the universalist approach and using the example of the Dental Discomfort Questionnaire adapted for Brazilian Portuguese-speaking parents/children before the validation testing.This study, approved by the Research Ethics Board of the Federal University of Goias (UFG), Brazil (#127/09), followed the Declaration of Helsinki’s principles. During each phase of the study, anonymity was guaranteed, and the participants  were informed about the research and asked to sign an informed consent form explaining the risks and benefits of the specific phase and the entire study.The study design was grounded in the universalist approach for cross-cultural adaptation –21. In pThe DDQ was first obtained from the author of the original version. Then, the DDQ conceptual equivalents for the Brazilian culture were investigated by reviewing the pertinent literature to understand the convergent and divergent points of conceptual equivalence for the questionnaire’s structure as well as dental pain perceptions in the target population. To improve the investigation of conceptual equivalence, the theme  was extensively discussed by pediatric dentists experienced in caring for children in a focus group.Item equivalence was assessed in the same focus group. Five Brazilian pediatric dentists (purposive sampling) invited to participate in the focus group discussed their perceptions about preschoolers’ dental pain  and abouThe decision regarding whether to continue the DDQ adaptation process for use in Brazil was based on the positive outcomes for the conceptual and item equivalences : (A) forBecause the languages for the source instrument (English) and the target instrument (Brazilian-Portuguese) are not similar, translation and back-translation were required . The semIn this study, the translations were performed by three independent translators who were native Brazilian-Portuguese speakers: a retired high school professor with a Bachelor’s degree in Arts and Languages (particularly English), a professional translator, and a bilingual health professional with clinical expertise in child dental care (the only one who was aware of the questionnaire’s intention and subject). Back-translations were also performed by three other translators living in Brazil who were native English speakers and fluent in the idioms and colloquial forms of the Brazilian Portuguese language but were uninformed about the intent of the DDQ.The back translations were compared with the original DDQ to solve any divergence problems, to determine the need for the elimination of any inadequate information for the target population and, finally, to present a preliminary consensus version  or to recommend another translation/back-translation process. The experts were a professor with experience in public health and epidemiological studies using questionnaires, two pediatric dentists with substantial clinical experience, and two professors with a large amount of expertise in cross-cultural adaptations of questionnaires.Operational equivalence was evaluated by applying the preliminary version of the Brazilian-Portuguese DDQ to 30 Brazilian caregivers of preschool children (convenience sample) attending the UFG dental clinic or university hospital and using cognitive interviews to assess the format and comprehensibility of the translated version , 24. CogAfter discussing the problems detected in the format and the difficulties reported by the respondents, the interviewer, one professor of pediatric dentistry and the main author of the original DDQ created the final version of the cross-cultural adapted Brazilian-Portuguese DDQ.The DDQ items and concepts were considered to be equally valid for testing in the Brazilian population. The items were found acceptable for use with minor or no modifications needed, excepted translation; thereby encouraging the study of other types of equivalence .The constructs employed in the development of the original DDQ were considered appropriate for use in the Brazilian culture. Toothache as reported by parents of Brazilian children was used for epidemiological purposes in the most recent national survey  and chilOut of five participants in the focus group two found that only one DDQ item (“Putting sweets away just after starting eating?”) was of little relevance because they argued whether parents could in fact relate this action to a toothache Table . HoweverStrategies for reviewing the literature and discussing items with dentists specialized in pediatric dental care were considered to be adequate for evaluating the relevance of the questionnaire in the target population, as described in the published guidelines , 19. MemA consensus-based preliminary Brazilian-Portuguese version was created by an expert panel that performed this process extensively reviewing the words, terms and expressions of the back-translated versions. After examining the meanings of terms in the three translated versions, all of the items were changed from the original DDQ to this preliminary version Table . ExtrapoBecause some children in Brazil are accompanied by their caregivers (such as grandmothers) and not their parents, the term “the child” was chosen instead of “your child” as a more appropriate reference for the child. Moreover, the experts suggested repetition of the initial question “Is your child” for each item to improve understanding. None of the modified terms affected the concept of the original DDQ, but the questions could be more easily understood by the respondents.There is a lack of standardization for the semantic equivalence phase, despite its relevance for the cross-cultural adaptation process . The steAll invited caregivers  participating in the cognitive interviews were categorized as having low socioeconomic status and filled out the questionnaire on behalf of their 1-5-year-old children. The probing method was chosen for cognitive interviewing to facilitate the interviews for respondents giving them the chance to do not feel depressed to fill out the questionnaire and to immediately resolve any questions , 31. ThiBecause the respondents found that the examples provided in the orientation part of the questionnaire (before the items) were somewhat confusing, researchers replaced them with two statements: “Please do not leave any question blank (no response)” and “Fill out the questionnaire by marking an “x” for the alternative that best matches your response for each of the questions”. In addition, the table format recommended by the expert panel was replaced by parentheses with a space to mark an “x” before each choice, which is a more commonly used format in Brazil . RespondThere is a lack of specific guidelines for the cross-cultural adaptation of scales for pain assessment, even knowing the complexity of cultural influence on the assessment of a child’s pain . TherefoThe cross-cultural adaption process of the Dental Discomfort Questionnaire was imperative before its final validation testing, because it enabled the researches to define DDQ as an instrument with universal concepts that could be used for Brazilian children after modifying its format and a few terms. The description of each phase of the cross-cultural adaptation is also relevant to inspire others to revise child pain assessment tools across different cultures.The Dental Discomfort Questionnaire .(PDF 217 KB)Additional file 1:The Dental Discomfort Questionnaire, Brazilian Portuguese adapted version.(PDF 209 KB)Additional file 2:


This work analyzed the perceptual attributes of natural dynamic audiovisual scenes. We presented thirty participants with 19 natural scenes in a similarity categorization task, followed by a semi-structured interview. The scenes were reproduced with an immersive audiovisual display. Natural scene perception has been studied mainly with unimodal settings, which have identified motion as one of the most salient attributes related to visual scenes, and sound intensity along with pitch trajectories related to auditory scenes. However, controlled laboratory experiments with natural multimodal stimuli are still scarce. Our results show that humans pay attention to similar perceptual attributes in natural scenes, and a two-dimensional perceptual map of the stimulus scenes and perceptual attributes was obtained in this work. The exploratory results show the amount of movement, perceived noisiness, and eventfulness of the scene to be the most important perceptual attributes in naturalistically reproduced real-world urban environments. We found the scene gist properties openness and expansion to remain as important factors in scenes with no salient auditory or visual events. We propose that the study of scene perception should move forward to understand better the processes behind multimodal scene processing in real-world environments. We publish our stimulus scenes as spherical video recordings and sound field recordings in a publicly available database. A real-world scene can be considered as spatial and temporal context that can be found in real life, where events, including human action, can occur. The human brain is constantly selecting and combining information from different sensory channels to structure the external physical environment, but the amount of sensory stimulation is too large to be fully processed by our limited neural resources. A bottom-up process is thought to control the early stages of scene processing, where sensory information is selected for further analysis based on perceptual saliency The perception of real-world scenes has been studied by analyzing saliency maps, the gist in the visual domain, and the soundscape in the auditory domain. Unimodal saliency maps have been shown to accurately predict the focus of attention especially in the visual domain Considering the perception of real-world environments, there is no clear knowledge about what environmental sounds people actually hear when they are not consciously listening for a particular sound Combining auditory and visual information seems to be beneficial for human perception in speech comprehension Finally, the applicability of unimodal saliency maps to real-world audiovisual scenes seems questionable without taking into account the integration of sensory information and its effects on attentional control. Therefore, as already stated, the aim of this study is to further understand the perceptual dimensionality in audiovisual perception of natural scenes. This is done by evoking real-world scene experiences in a laboratory setting through ecologically valid audiovisual reproduction, and asking participants to categorize the scenes based on their perceived similarity. The empirical goal is to acquire a mapping of a diverse set of audiovisual stimuli along with perceptual attributes to study the human interpretation of real-world urban scenes. Our primary interest is to find whether a group of people is able to create a consistent low-dimensional perceptual representation for a set of natural scenes, and what are the perceptual attributes that are referred most often. Furthermore, objective environmental variables related to the loudness, dynamic visual information and indoor vs. outdoor classification are computed from the stimulus scenes, and fitted to the obtained perceptual mapping. Our hypothesis here is that the perceptual map originates from the physical world, instead of, for example, from functional attributes of the depicted spaces, and the subjective perceptual mapping should be predictable by physical properties of the stimuli.A two-dimensional perceptual map of audiovisual scenes was derived in our study, confirming our hypothesis that a group of people describes natural scenes with similar perceptual attributes. The nature of our study was exploratory and thus we cannot precisely identify the relative contributions of the two sensory channels to the audiovisual scene perception. However, from the perceptual map we can draw evidence that the most important perceptual attributes in natural scenes depicting urban environments are the amount of movement, perceived noisiness, and eventfulness of the scene. Scene gist properties openness and expansion were found to remain as important attributes in scenes with no salient auditory or visual events.The participants voluntarily registered for the study through an online scheduling program in advance after reading an outline of the study and its aim. In addition, the participants provided verbal informed consent to voluntarily participate in this study at the examination day after receiving detailed information about the contents of the study, and they were aware that they could withdraw from the study at any time. It was also stated, that the gathered data was anonymous and not traceable back to the participants. Only demographic information about the participants was collected. There is a voice recording made of every participants' interview confirming the verbal consent. Therefore, no written informed consent was considered necessary, as outlined in the Finnish Advisory Board on Research Ethics' proposal A total of 30 naive participants took the test. They were recruited through social media and Aalto University's student mailing list. Nine of the participants were female and the average age was 26.5 (SD  = 6.6). All the participants reported to have normal or corrected-to-normal vision and normal hearing. No acuity screening or audiogram measurements were considered necessary, because the participants were supposed to perceive and assess the reproduced environments as they would experience ordinary situations in their everyday lives without relative weighting of the modalities. All the participants, except for one, were familiar with most of the locations of the outdoor scenes in the study, and reported to live or having lived in the Helsinki metropolitan area. Each participant reported having Finnish as their native language. The participants received a movie ticket as a compensation for their contribution. The authors did not participate in the experiment.Tram, the passing-by event lasts for the whole duration of the scene. The recording device, and thus the observer, stays static in all the cases. The stimuli used in the experiment are listed in a priori categorization of the scenes according to their objective environmental attributes. A frame capture of each content is shown in http://www.acoustics.hut.fi/go/plosone14-avscenes/ . The scenes #Cafeteria and #Class room are not published due to limited rights of publication.All stimulus scenes were recorded either indoor, or during summertime in an urban environment in the greater-Helsinki area, Finland. The aim was to provide as rich stimulus set as possible with clear perceptual  gradients, even though the requirement of finding a real-world environment with desired properties was sometimes challenging. The scene duration is 15 s, and the sequences are constructed so that the scene, and the events taking place in the scene, stay as invariant as possible. For example, in the scene #The stimulus selection was based on previous studies of categorization of environmental scenes, where the scenes were divided according to their superordinate, basic and subordinate levels of categorization The experiment was conducted in an immersive audiovisual environment located at the Department of Signal Processing and Acoustics in Aalto University School of Electrical Engineering. The environment is built inside of an acoustically treated room and consists of three high-definition video projectors producing a horizontal field-of-view of 226° at the viewing position on three acoustically nearly transparent screens. The screens are 2.5×1.88 m each and installed to follow the shape of the base of a pentagon. The display area extends to the ground. Distance from the observation position to the center of each screen is 1.72 m. More detailed information about the technical specifications can be found in The videos were captured with a recording device capable of producing a spherical video (Point Grey Research: Ladybug 3). The videos were cropped to reproduce a 226° slice of the full circle on the screen, making the visual scene consistent with the auditory scene. The video was recorded and reproduced at 16 frames-per-second and the resolution of the final video was 4320×1080 pixels produced by the three projectors. With this resolution and viewing distance, the inter-line distance is 3.5 arcmin, which affects the sharpness of the image, but the objects in the scene are still easily recognizable.The audio reproduction system consisted of 29 loudspeakers (Genelec 1029). The loudspeakers were located on a sphere with a 2.1 m radius centered at the observation position. The loudspeaker layout and the projection screen setup are depicted in First, the participants were familiarized with the stimulus scenes by watching and listening the whole list of 19 scenes presented in a random order. Thereafter, the participants were instructed to freely categorize the scenes into three or more groups, and to avoid groups with only single stimulus. The motives for the categories were left for the participants to decide. The categorization had to be based on the perceived similarity of attributes of the reproduced scenes. Examples of bad attributes were said to be forming groups based on personal familiarity with the depicted space or personal significance that the space might have for the participant. In addition, an analogous case of finding discriminating attributes between three orange juices was described to the participants. In such a case, the question is how to describe the juices and maybe recommend one of them to someone who has not tasted them. As one cannot discriminate between the juices by saying that they taste like orange, they should find something essential about the taste. Similarly with the scenes, it is maybe possible to describe a given scene in a way that sets it apart from some and resembles others.play button that the participants could use to watch the stimuli as many times as necessary. Also, a progress bar was provided. A stimulus was selected for playback by touching the corresponding icon and clicking the play button. The stimulus would then be played once.Participants performed the free categorization task on a tablet computer with a touch screen (Apple iPad2). The graphical user interface is depicted in min  =  30 min, max  =  80 min, SD  =  12 min).It was stressed to the participants that they were not required to determine a global categorization rule. They should not think of the screen as having x- and y-axis describing some global features, but rather, the screen provided them with a plane on which to build the categories, each with their own similarity attributes. After the participant was content with the acquired categorization, a semi-structured interview took place. All interviews were conducted by the same person (first author). In the interview, the participants were asked to give short descriptive names for the categories, and thereafter, each of the categories was examined by a two-level interview process. For each group, the interviewer first asked why the participant had allocated the chosen stimuli into the given category. The reasons were supposed to be related to the perceived attributes of the scene. Next, the interviewer asked more specifically about the properties of the attributes the participant had mentioned. Basically, the interviewer aimed at finding the underlying reasons affecting the categorization by asking consecutive “why”-questions about the attributes the participant had paid attention to. The interview was conducted in Finnish and the interviewer took notes of the answers. In addition, a voice recording was made of every interview in case the interviewer needed to verify details afterwards. On average, the entire test took 45 minutes to complete , and correspondence analysis (CA). The analysis methods make different assumptions of the underlying data, the hierarchical clustering having the least amount of assumptions, and thus it can be used to verify the following two analyses. The MDS and CA methods use different datasets, that is, the dissimilarity matrices and the interviews. The MDS was necessary to inspect the variation in the participants' categorization strategies, and the CA was important in revealing the perceptual attributes' relation to the stimulus scenes. Finally, having similar overall ordination from the two methods, originating from different datasets, adds more support to the validity of both the solutions. Overall schematic of the analysis methods and the data used in each test is depicted in The perceived similarity of the scenes was extracted from the individually formed categorizations of the scenes. A symmetric and non-negative dissimilarity matrix with zero diagonal was formed for each participant. The matrix was constructed from pair-wise dissimilarities of the scenes by denoting scenes that were in the same category as having pair-wise dissimilarity value of 0 with each other, and dissimilarity value of 1 with scenes in other categories. An example of such dissimilarity matrix is depicted in The idea behind hierarchical clustering is to obtain a baseline interpretation of the high-dimensional dataset. In further analysis, the baseline clustering can be used to validate the more detailed and subjective interpretations by inspecting if the clusters remain separated. In addition, by clustering the stimulus scenes into groups, the interpretation of perceptual maps in subsequent analysis is potentially easier. Overall dissimilarities were calculated by summing the 30 dissimilarity matrices together, and by using Bray-Curtis dissimilarity The dissimilarity matrices were further analyzed by multidimensional scaling (MDS), which is an exploratory data analysis technique well suited for identifying unrecognized dimensions that the participants could have used when making the categorization The individual dissimilarity matrices were analyzed using the R The interview data was searched for expressions that could be coded under broader terms. The coding process was based on the grounded theory principle, where a phenomenon is analyzed and a theory formed beginning from the data veganCorrespondence analysis CA;  was perfThe CA is able to attenuate the effect of categories formed based on higher-level cognitive reasoning, for example personal significance of a place or knowledge of the social function of the space. This kind of categories would be attached with codes with small number of references, and thereafter they would be ruled out of the actual analysis process, since only the most frequent codes were allowed into the CA model. In effect, the CA should reveal the underlying perceptual dimensions that actually stem from the perceivable physical environment.Inspecting the subjective categorizations reveals that the participants formed 5.4 categories on average, with minimum amount of three categories and maximum of eight categories. Calm. Cluster #2 includes visually calm outdoor scenes with some ambient sound, well described by the word Still. In contrast, Cluster #3 contains noisy outdoor and indoor scenes with modest movement, therefore it is denoted Noisy. Cluster #4 consists of large indoor spaces with lots of people, movement and sound, in other words, the cluster is Vivid. Finally, Cluster #5 contains both outdoor scenes and large indoor spaces with people, modest movement, and some sonic events. The last cluster is best described as being visually Open.Cluster #1 is the largest and contains calm sonic and visual environments, both from indoor and outdoor. Therefore, the holistic name given to Cluster #1 is Individual differences scaling (INDSCAL) models with dimensionalities ranging from two to five were fitted to the data, and the resulting nonmetric stress values were: .32, .16, .09, and .05, respectively. In this study, an INDSCAL model with three dimensions was found to explain the variance of the data with good quality  and #Lecture hall (Dimension 1  =  0.68). In contrast, noisy and busy outdoor and indoor scenes, for example #Railway station (Dimension 1  =  −0.77) and #Traffic (Dimension 1  =  −0.56), are negatively weighted for the Dimension 1. It can be stated that Dimension 1 appears to be related to the perceived calmness of the scenes, where both auditory and visual content affect the perception. The result is validated by observing Cluster #1  having the highest weights and Clusters #3 (Noisy) and #4 (Vivid) having negative weights on Dimension 1.Multidimensional scaling was performed on the categories formed by the participants without any interpretation. Therefore, categories based on higher-level cognitive functions, with little or no correspondence to the perceptual attributes of the space, affect the obtained result. However, it is beneficial to inspect the raw categorization and the participant integrity before interpreting the results further. In Hall (Dimension 2  =  0.32) and #Subway station (Dimension 2  =  0.47). Indoor scenes and limited outdoor scenes receive negative weights on Dimension 2, therefore, it can be assumed to describe the openness of the scene. Temporal aspects, both auditory and visual, seem to have no impact on Dimension 2, since Clusters #1 and #4 containing the calmest and busiest scenes obtain similar weights. Finally, Dimension 3 is more difficult to characterize by examining the environmental attributes. It seems, that scenes with people present in the view, such as #Hall (Dimension 3  =  0.46) and #Cafeteria (Dimension 3  =  0.43), have the highest weights on Dimension 3, whereas scenes with no people have negative weights.Dimension 2, on the other hand, appears to yield the highest weights for outdoor scenes, or distinctly large indoor spaces, such as #Inspection of κ  =  .62 according to κ ≤ .79 as substantial and κ > .80 as outstanding.The individual motives for categorization were inspected by analyzing the interview data. Correspondence analysis was used to relate the elicited perceptual attributes to the stimulus scenes and, at this point, attributes with only a few references in the data were excluded. In the analysis, only the 16 most frequent codes, presented in From the 16 most frequent codes, five are related to dominantly visual content, six to auditory and five can be considered as audiovisual, or bimodal, codes. However, the relative weights of the modalities were not inspected in this study, and thus we cannot state that only visual input affected to the codes labeled here as visual, and vice versa for the auditory labels. Each of the unimodal-labeled codes have most likely been impacted by both modalities to some extent. Calm) resides close to codes reflecting perceived pleasantness and calmness mainly induced by quietness and soundscape with recognizable auditory events. In addition, codes reflecting visual movement are on the opposite side of the map, implying that the visual scene was still, although there were not enough references to codes indicating visual stillness. Cluster #2 (Still) is best described in the perceptual map by attributes related to being outdoor or in an open place. The scenes in this category did not have any specific points of interest or events and the overall atmosphere was still. This is reflected in the ordination through the absence of attributes related to temporal aspects, in favor of gist-like attributes of scene openness and background sound.In Noisy) contained scenes with lots of mechanical noise. The noisiness is well reflected in the perceptual map. In addition, the participants paid attention to the sound source, namely traffic. According to the ordination, Cluster #4 (Vivid) is defined to contain scenes with a lot to attend, which is consistent with the clustering result. Especially, attention has been paid to the presence of people in the scenes. Interestingly, a spatial attribute of the soundscape, echo or reverberation, has been frequently mentioned. Finally, Cluster #5 (Open) is related with multiple attributes, the most common attribute being conversation. Attention was also paid to movement, enclosure and other recognizable sounds. Although all the scenes were somehow open spaces, the attributes related to openness are not ordinated close to the cluster. Apparently, with these scenes, other perceptual properties overruled the scene gist categorization.Cluster #3 , which is in accordance with previous research Movement, or the lack thereof, appears to be the most useful attribute in bimodal scene perception. As identified in previous research, visual movement and on-sets quickly draw our attention and direct fixations Narrow space and #Cyclists, the gist properties were the things that the participants noticed. Related to the size of a space, the perception of reverberation or echo was frequently mentioned with large indoor spaces. In previous research on soundscape perception, the spatial factors were seldom mentioned by test participants everyday listening, while in a laboratory the listening strategy is more analytic, musical listeningEven though the stimulus duration was 15 s, scene gist dimensions openness and expansion seem to be robust features also in dynamic audiovisual perception. These dimensions are perceived within a single glance of the visual world The auditory scene attributes appear to be divided to quiet scenes, scenes with recognizable or meaningful sound events (conversation), background sound and noise. The division is in accordance with the finding of event sequences and amorphous sequences Calm and #Pleasant, may not be readily usable for modeling, but need more elaborate investigation to relate them to perceivable scene properties. The effect of top-down information on real-world scene perception through attention allocation is also worth investigating. Arousal can have modulating effects on selective attention giving more attentional resources for the processing of the most salient stimuli while decreasing the processing of low priority stimuli Based on our exploratory results, humans tend to focus on perceived movement, noisiness and eventfulness when describing their experience of real-life urban environments. However, the relative weights of the modalities cannot be quantified with our data, and future studies will be needed. Moreover, some of the elicited attributes, namely #In conclusion, audiovisual perception of natural scenes was studied in this work. Perceptual similarity of 19 natural scenes reproduced with an immersive audiovisual display was evaluated through a categorization task followed by a semi-structured interview. Our exploratory results point out that a two-dimensional perceptual map of a set of natural audiovisual scenes depicting real-life urban environments is obtainable, and movement, noisiness and eventfulness of the scene are the most important perceptual attributes. Scene gist properties describing the size and openness of the space were present in the results, when there was an absence of salient events. However, we cannot state what exactly were the individual contributions of the modalities, or that the elicited perceptual attributes are stemming from perceptual saliency.Overall, when considering a real-world scene, including the auditory modality has an enormous impact on our perception. We propose that the study of natural scene perception should move forward to better understand the processes behind real-world scene processing including multiple modalities. Moreover, the question of how do we arrive from the gist of the visual scene to a thorough understanding of the multimodal reality is worth investigating. The current work is an exploratory study that demonstrates the existence of frequently used perceptual scene attributes. Further studies are needed to quantify the individual contributions of auditory and visual modalities on audiovisual perception of natural scenes.


Empirical evidence pertaining to the influence of treatment preferences on attrition, adherence and outcomes in intervention evaluation trials is inconsistent. The inconsistency can be explained by the method used for allocating treatment and measuring preferences. The current methodological study is designed to address these factors by implementing the two-stage partially randomized or preference trial design, and administering a validated measure to assess participants’ preferences for the treatments under evaluation. It aims to compare attrition, adherence and outcomes for participants allocated randomly or by preference to treatment. The study is in its final stages of data collection; its protocol is presented in this paper.A partially randomized clinical or preference trial is used. Eligible participants are randomized to two trial arms. First is the random arm involving random assignment to treatments, and second is the preference arm involving allocation to the chosen treatment. Participants with chronic insomnia are targeted. Two behavioral treatments are offered, stimulus control therapy and sleep restriction therapy, in the same format  and dose (two sessions given over a 4-week period). A participant log is used to collect data on attrition. Adherence is evaluated in terms of exposure and enactment of treatment. Sleep-related outcomes (sleep parameters and perceived insomnia severity) are measured at pretest, posttest, 6 and 12 month follow-up. Treatment preferences, adherence and outcomes are assessed with reliable and valid measures.The advantages and limitations of the preference trial design are highlighted. The challenges in implementing the trial are discussed relative to the distribution of participants in the groups defined by treatment received and method of treatment allocation.NCT02513017ClinicalTrials.gov Registry  Treatment preferences represent people’s choice of therapy . TreatmeThis paper describes the study protocol for conducting the two-stage partially randomized clinical or preference trial. The paper begins with an explanation of the rationale for the study. The trial protocol is described, and challenges in its implementation are presented. The advantages and limitations of the design are also discussed.The influence of treatment preferences on attrition, adherence, and outcomes has been investigated in several studies evaluating medical, behavioral and educational interventions for a variety of clinical conditions. The studies’ findings were synthesized in systematic reviews and meta-analyses. Overall, they point to inconsistencies as summarized next.Three individual studies –7 and onThe results of five individual studies were consistent in showing that assignment to treatment, matched to participants’ preferences, is associated with enhanced adherence operationalized as attendance at treatment sessions , 12–14 oThe findings of one systematic review  and two Conceptual and methodological factors could have contributed to the inconsistent findings and the small-to-moderate effect sizes quantifying the impact of treatment preferences on outcomes. These factors include differences in the characteristics of the target populations (e.g. patients with depression or heart disease), the types of treatment under investigation , the context of treatment implementation , the method of allocation to treatment, and the method for assessing preferences. The latter two methodological factors are of concern because they could have attenuated the estimates of the association between preferences and outcomes and they can be addressed in future research aimed to evaluate the influence of treatment preferences. Most previous studies consisted of randomized clinical trials in which participants, whose preferences were assessed at baseline, were randomized to treatment groups. The random method of assignment ignored participants’ preferences; however, these preferences were accounted for at the stage of data analysis by generating a match-mismatch (i.e. whether the received treatment was congruent with the preferred treatment) between-subject factor. The extent to which active involvement of participants in treatment selection and allocation to the preferred treatment make a difference in attrition, adherence, and outcomes has not been extensively investigated.In the majority of trials reviewed, the method for assessing preferences consisted of administering one item inquiring about participants’ choice, which has three limitations. First, the use of one item, with no demonstrated psychometric properties, could have introduced measurement error, raising questions about the accuracy of the expressed treatment preference in reflecting participants’ choice. Second, the trials’ reports provided minimal details regarding the treatment-related information presented to participants prior to eliciting their preferences, and the format in which such information was given. The content and format for presenting treatment-related information affect participants’ perception of the treatment options –20.Third, single items do not capture the complexity of treatment preferences, which are based on careful evaluation of the treatments’ attributes such as effectiveness, severity of side effects, and convenience of implementing the treatment in daily life –23. TherThe two methodological factors were addressed in the current study. The method of allocation to treatment was examined by applying the two-stage partially randomized clinical trial  that invTo compare participants randomized to treatment and participants allocated to the preferred treatment on: attrition, adherence to treatment, and outcomes.Among randomized participants, to compare those who received matched (i.e. congruent with expressed preferences) and those who received mismatched (i.e. incongruent with expressed preferences) treatment on: attrition, adherence to treatment, and outcomes.The goal of the current study was to clarify the contribution of treatment preferences in intervention evaluation research. The specific study objectives were:A two-stage partially randomized clinical or preference trial (PRCT), originally described by Rücker , was useThe treatments investigated in the current study are two behavioral therapies that demonstrated efficacy in the management of chronic insomnia: stimulus control therapy and sleep restriction therapy . EligiblParticipants with insomnia are recruited through community media advertisements in local newspapers, radio station, and local newsletters targeting middle-aged and older adults. Flyers advertising the study are distributed to community health centers, hospital outpatient clinics, a leisure complex for older adults and sleep clinics.Persons with insomnia are eligible for the study if they 1) are non-institutionalized adults (≥40 years of age) as insomnia is prevalent in middle-aged and older adults , 2) haveThe sample size is estimated to attain adequate power to determine the effects of treatment preferences on attrition, adherence, and sleep outcomes. Sample size estimation also considers the repeated measure feature of the design. Within-subject designs require a smaller number of participants than between-subject designs, to achieve the same statistical power . A mediuStimulus control therapy is a behavioral treatment for the management of chronic insomnia. It aims to assist persons with insomnia to re-associate the bed and the bedroom with falling asleep or back to sleep, and to acquire a consistent sleep pattern. This therapy entails specific instructions that focus on developing new sleep habits, such as avoiding activities  in bed, getting out of bed if unable to fall asleep or back to sleep within 15–20 min and engaging in quiet activities until sleepy, going to bed only when sleepy, and waking up at the same time everyday.Sleep restriction therapy consists of limiting the amount of time spent in bed to a specific sleep time. Sleep time is individualized, based on the persons’ total sleep time identified by reviewing the daily sleep diary kept at pretest. A sleep-wake schedule is planned to fit the persons’ lifestyle. The sleep-wake schedule is changed to accommodate improvements in the persons’ sleep, over time.Both treatments are given by Master’s prepared therapists, trained in the implementation of the behavioral therapies. The sessions are offered in a small group (4–6 persons) format, based on availability of participants and to avoid any delay in treatment receipt. The treatments are delivered in the same dose: two sessions of 90 min each, once every 15 days, over a 4-week treatment period.The results of two systematic reviews consistently demonstrated the effectiveness of stimulus control therapy and sleep restriction therapy , 31. TheSocio-demographic characteristics of participants are assessed with standard questions gathering information on age, sex, marital status, level of education, employment status, and ethnicity.Clinical characteristics relate to the type of insomnia , whether the insomnia is primary  or comorbid (associated with the occurrence of such problems), and duration of insomnia. These are assessed with relevant items of the Insomnia Interview Schedule developed and validated by Morin [by Morin . ParticiPreferences for treatment are measured with an adapted version of the Treatment Acceptability and Preference scale [not at all (0) to very much (4) is used. The second section of the Treatment Acceptability and Preference (TAP) presents the description of the alternative treatment, and the items for rating it. The third section includes two questions asking participants to indicate if they have a preference for any treatment and, if they do, the preferred treatment. In this study, the nine items rating the attributes of the two behavioral therapies are internally consistent  and valid, evidenced by significant associations between the treatments’ ratings and the expressed preferences. The order for presenting the treatment options is randomized to avoid an order effect.ce scale . It contAttrition is noted and documented in a log. The research assistants record the following information for each participant: completion of pretest measures, attendance at treatment sessions, completion of post-test, 6-month and 12-month follow-up measures, time at which the participant withdraw and reasons for withdrawal as reported by participants. Attrition rate will be computed as the percentage of participants who drop out of the study at any time after providing consent to take part in the trial.Two components of adherence to treatment are examined: exposure and enactment. Exposure is operationalized as participants’ attendance at the planned treatment sessions. The therapist facilitating the sessions records the presence of each participant and the total number of sessions attended will be counted. Enactment represents the extent to which participants apply the treatment recommendations in daily life. It is assessed by having participants complete a checklist. The checklist was developed following the procedure described by Stein and colleagues [lleagues . It inclSleep outcomes include sleep parameters and perceived insomnia severity. The sleep parameters are assessed with the daily sleep diary (DSD) completed for a week, at each data collection point and during the 4-week treatment period. The DSD is a self-administered log of nightly sleep behaviors, developed by Morin [by Morin . Particiby Morin . RelevanPerceived insomnia severity is measured with the Insomnia Severity Index (ISI). The ISI has seven items assessing distress with the sleep problem and satisfaction with sleep patterns. The ISI demonstrated acceptable internal consistency reliability (α ≥ .85) and validity as evidenced by correlation with other subjective and objective measures of insomnia severity .Objective 1: Chi-square test will be used to compare the number of participants who withdrew from the study across the four study groups defined by the type of treatment received (stimulus control therapy and sleep restriction therapy) and the method of allocation to treatment (random and preference). One-way analysis of variance will be applied to examine differences in level of adherence (i.e. attendance to treatment sessions and enactment of treatment recommendations), and the pattern of change (estimated with a slope) in the sleep outcomes, across groups.Objective 2: Chi-square test will compare the number of dropouts between participants in the random arm who receive matched and mismatched treatment. Independent samples t-test will examine differences between the matched and mismatched subgroups in levels of adherence (exposure and enactment) to treatment and the pattern of change in the sleep outcomes.In addition to descriptive statistics to characterize the participants in terms of their demographic and clinical characteristics, the following analyses are planned to address the study objectives:The study is in its final stage of collecting outcome data for the 12-month follow-up. To date, 421 persons showed interest and agreed to undergo initial screening.The study extends previous research on the role of treatment preferences in intervention evaluation research in two ways. First, the two-stage PRCT design is applied, which is considered the most appropriate design for evaluating the influence of treatment preferences because of its advantages. The PRCT design is useful to dismantle the influence of treatment preferences from the impact of treatment on attrition, adherence and outcomes. This is accomplished by creating groups of participants who receive the same treatment randomly or by preference; comparison of these groups indicates the contribution of treatment preferences to attrition, adherence and outcomes. The PRCT design also minimizes the potential for selection bias resulting from non-comparability of participants assigned to different treatments randomly or on the basis of preference , 10. TheSecond, the study uses a systematic method for assessing treatment preferences. The method begins by providing information on the treatments’ goals, components, activities, mode and dose of delivery, benefits and risks; it proceeds by having participants rate each treatment relative to four attributes prior to indicating their preferences. The TAP measure operationalizes this systematic method, has sound psychometric properties, and is expected to accurately capture participants’ preferences.Despite its advantages, there are some challenges in carrying out a two-stage PRCT. The first challenge relates to the first stage of randomization. Through the process of obtaining informed consent, participants are informed of the two stages and of the method for treatment allocation within each arm. Participants with strong treatment preferences may be unwilling to leave treatment choice to chance and they may desire allocation to the preference arm. If randomized to the random arm, they may react unfavorably  and withThe second challenge in the implementation of the two-stage PRCT relates to the method of treatment allocation applied in the second stage of the trial. At this stage, participants in the random arm are randomized to treatment, yielding a balanced number of participants assigned to the treatment groups. However, the equality of the treatment groups’ sizes is not achieved in the preference arm if most participants choose one treatment over the other. Large differences in group sizes may yield unequal within-group variances; if not addressed with appropriate statistical formula, unequal variances may reduce the power to detect significant treatment and preference effects . The valThe third challenge in conducting the two-stage PRCT relates to the reactions of participants assigned to treatment on the basis of chance or preference. Specifically, participants in the random arm may have preferences for the treatments under investigation. Those randomized to the non-preferred treatment may react unfavorably. In contrast, participants in the preference arm may react favorably because they get the treatment they desire. These reactions may influence the participants’ adherence and responses to the allocated treatment.Empirical evidence suggests that preferences for treatment contribute, to some extent, to participants’ attrition and adherence, and achievement of outcomes. Research designs, methods, and strategies are needed to account for treatment preferences and explore their influence on attrition, adherence, and outcome achievement with the ultimate goal of enhancing validity of conclusions in intervention evaluation research. The two-stage PRCT design is a viable alternative that allows for comparisons of participants representing the same target population and assigned to the same treatment on the basis of chance or preference. Just like other designs, the two-stage PRCT has advantages and limitations, and its application poses some challenges. The challenges relate to ignoring participants’ preferences in the random arm of the trial; this in turn, may trigger a sense of disappointment and dissatisfaction associated with depriving participants with the act of choosing the treatment.Assignment to the preferred treatment within the context of intervention research is consistent with the process of treatment selection advocated and often applied in the context of day-to-day practice. In the latter context in which the patient-centered approach to care is emphasized, patients are informed of alternative treatments for the management of the presenting clinical problem, involved in treatment decision making, and provided the treatment that is responsive to their needs and preferences . Results


Tracheobronchopathia osteochondroplastica (TPO) is a rare benign disorder of the lower part of the trachea and the upper part of the main bronchi. A case of tracheobronchopathia osteochondroplastica (TPO) diagnosed at the time of intubation in an intensive care unit due to difficulty when advancing the endotracheal tube beyond the vocal cords, is reported. A problem was encountered which had not been reported previously in TPO: repeated cuff rupture at the time of surgical tracheostomy occurred possibly because of bony and cartilaginous tissue located in the tracheal wall.In addition to difficulty of intubation, TPO may cause tracheostomy tube cuff rupture, which could be explained due to bonny calcification in the tracheal wall.  Tracheobronchopathia osteochondroplastica (TPO) is a rare benign disorder of the lower part of the trachea and the upper part of the main bronchi -3. RokitThe etiology, pathology, and natural history of TPO are unclear. Aschoff attributed it to a cartilaginous metaplasia of the sub epithelial connective tissue, which might well involve both calcification and ossification. It has also been suggested that it arises as a final evolutive stage of tracheobro -nchial amyloïdosis. Other hypotheses have been formulated: exostosis arising from the cartilaginous ring, local metabolic or inflammatory factors and infections, or chemical irritation. No direct relationship with either calcium or phosphorus metabolism has been established. Most patients affected with TPO are asymptomatic; and, rarely, the first presentation may be in the operating room during intubation, as has been presented previously in literature -8.A case of TPO, with difficult intubation during airway management in an intensive care unit and with repeated rupture of the tracheostomy tube cuff at the time of surgical tracheostomy, is presentedA 67-year-old man was brought to emergency room with vertigo and ataxia 8 hours prior to admission. His head CT showed hypodencity in the left side of the medulla. His old chart showed that the basilar artery had 90 percent stenosis in a 4-vessel angiography. Following this, he has been scheduled for stent placement but it had been canceled because of the inability to intubate the patient after general anesthesia. He was subsequently referred to an optional ENT visit, which didn’t show any problem in indirect laryngoscopy, and a fibroptic evaluation of the lower airway was recommended. The following day, he developed dense right sided hemiplegia and respiratory distress and it was decided to intubate the patient; however, it was not possible to pass the 8.0 mm endotracheal tube (ETT) beyond the vocal cords. A smaller diameter tube  was placed in the larynx; however, the ETT was no able to advance but for a few centimeters from the vocal cords and it was fixed at 18 cm from the lips. The patient was transferred to an intensive care unit while he was conscious with right-sided weakness and had a massive air leak around the ETT during mechanical ventilation. Direct laryngoscopy was performed and the ETT was changed to a larger one; however, it was not possible to advance the ETT deeper into the trachea. Fibroptic bronchoscopy (FOB) showed nodular mucosal hypertrophy, all over the trachea extending to the carina and main bronchi, which spared the membranous part; therefore, TPO was diagnosed bronchos- copically as the reason for difficult intubation . An Armored ETT (size 8) was passed into the trachea. Spiral chest CT showed that the trachea had very irregular borders ,3.In the following days he had a drop in his consciousness and repeat head CT showed more hypodencity in the pons and new hypodencities in the cerebellum. He was scheduled for surgical tracheostomy. During the open surgical tracheostomy, which was done by a thoracic surgeon, the trachea was stony hard and a tissue was sent for pathology from the tracheal wall, which showed fibrofatty tissue with bone formation . Another issue was repeated perforation of the tracheostomy tube cuff, which occured even after changing the tube 3 times during the tracheostomy procedure. There was a massive air leak around the tracheostomy tube after transferring the patient to ICU. Because of the inability to ventilate the patient, a laryngeal mask airway (LMA) was placed and the distal end and was clamped as a way to prevent massive air leak. Then the tracheostomy tube was removed and another one was passed into the trachea and this time the ETT cuff showed no perforation. TPO presented at the time of intubation has been reported previously during general anesthesia -7. The sAnother problem, which has not been reported previously, was repeated perforation of the tracheostomy tube cuff, which was encountered by the thoracic surgeon at the time of surgical tracheostomy. Perforation of cuff had occurred three times during tracheostomy tube insertion. Considering the fact that there was calcification and ossification observed during tissue biopsy, repeated rupture of the tracheostomy cuff could be explained by the trauma to the cuff due to the presence of bonny tissue in the tracheal wall. Due to large amounts of air leaks post tracheostomy, because of the damaged tracheostomy cuff, a classic laryngeal mask airway was used as a temporary measure to block the air leak through the mouth.Use of the laryngeal mask to prevent massive air leak at the time of trachioplasty has been reported previously by Eckhardt et al. . TPO may present itself for the first time during ICU admission and the tracheostomy cuff may be damaged by the bony growth in the tracheal wall.