Octopaminergic neurons have multiple targets in Drosophila larval mushroom body calyx and can modulate behavioral odor discrimination.

Discrimination of sensory signals is essential for an organism to form and retrieve memories of relevance in a given behavioral context. Sensory representations are modified dynamically by changes in behavioral state, facilitating context-dependent selection of behavior, through signals carried by noradrenergic input in mammals, or octopamine (OA) in insects. To understand the circuit mechanisms of this signaling, we characterized the function of two OA neurons, sVUM1 neurons, that originate in the subesophageal zone (SEZ) and target the input region of the memory center, the mushroom body (MB) calyx, in larval Drosophila We found that sVUM1 neurons target multiple neurons, including olfactory projection neurons (PNs), the inhibitory neuron APL, and a pair of extrinsic output neurons, but relatively few mushroom body intrinsic neurons, Kenyon cells. PN terminals carried the OA receptor Oamb, a Drosophila α1-adrenergic receptor ortholog. Using an odor discrimination learning paradigm, we showed that optogenetic activation of OA neurons compromised discrimination of similar odors but not learning ability. Our results suggest that sVUM1 neurons modify odor representations via multiple extrinsic inputs at the sensory input area to the MB olfactory learning circuit.

The association between nonrestorative sleep and health-related quality of life in Chinese adults: a cross-sectional study.

PURPOSE: Sleep problems are prevalent among the general population and can cause various health problems, which may lead to decreased quality of life. However, little is known about nonrestorative sleep and its implications. This study aimed to examine the association between nonrestorative sleep and health-related quality of life (HRQL) in Chinese adults. METHODS: Data were collected through a cross-sectional study of 500 adults in Hong Kong (66.4% female, average age of 39 years). The Short-Form-12 Health Survey version 2 (SF-12v2), Nonrestorative Sleep Scale (NRSS), Pittsburgh Sleep Quality Index, ENRICHD Social Support Instrument, Patient Health Questionnaire, Perceived Stress Scale, and Hospital Anxiety and Depression Scale were administered. Objective sleep parameters were based on participants' sleep condition over 1 week, as measured using an ActiGraph GT9X Link. RESULTS: Mean standardized scores for the physical component summary (PCS) and mental component summary (MCS) of the SF-12v2 and the NRSS were 50.33 ± 6.50, 49.00 ± 9.03, and 64.77 ± 12.75, respectively. After adjusting for sociodemographic and lifestyle characteristics, sleep quality, objective sleep parameters, social support, somatic symptoms, stress, anxiety, and depression, NRSS scores were associated with PCS (b = 0.12, 95%CI: 0.06 to 0.18, p < 0.001) and MCS (b = 0.08, 95%CI: 0.02 to 0.15, p = 0.013) scores. Furthermore, associations of NRSS score with PCS as well as MCS scores were stronger in women than in men. CONCLUSION: Nonrestorative sleep is a potentially modifiable risk factor for poor HRQL. Thus, interventions to relieve or decrease nonrestorative sleep could be beneficial for improving HRQL.

Swimming kinematics and hydrodynamics of barnacle larvae throughout development.

Changes in size strongly influence organisms' ecological performances. For aquatic organisms, they can transition from viscosity- to inertia-dominated fluid regimes as they grow. Such transitions are often associated with changes in morphology, swimming speed and kinematics. Barnacles do not fit into this norm as they have two morphologically distinct planktonic larval phases that swim differently but are of comparable sizes and operate in the same fluid regime (Reynolds number 100-101). We quantified the hydrodynamics of the rocky intertidal stalked barnacle Capitulum mitella from the nauplius II to cyprid stage and examined how kinematics and size increases affect its swimming performance. Cyprids beat their appendages in a metachronal wave to swim faster, more smoothly, and with less backwards slip per beat cycle than did all naupliar stages. Micro-particle image velocimetry showed that cyprids generated trailing viscous vortex rings that pushed water backwards for propulsion, contrary to the nauplii's forward suction current for particle capture. Our observations highlight that zooplankton swimming performance can shift via morphological and kinematic modifications without a significant size increase. The divergence in ecological functions through ontogeny in barnacles and the removal of feeding requirement likely contributed to the evolution of the specialized, taxonomically unique cyprid phase.

Nonrestorative sleep scale: a reliable and valid short form of the traditional Chinese version.

PURPOSE: Previous research has suggested the essential unidimensionality of the 12-item traditional Chinese version of the Nonrestorative Sleep Scale (NRSS). This study aimed to develop a short form of the traditional Chinese version of the NRSS without compromising its reliability and validity. METHODS: Data were collected from 2 cross-sectional studies with identical target groups of adults residing in Hong Kong. An iterative Wald test was used to assess differential item functioning by gender. Based on the generalized partial credit model, we first obtained a shortened version such that further shortening would result in substantial sacrifice of test information and standard error of measurement. Another shortened version was obtained by the optimal test assembly (OTA). The two shortened versions were compared for test information, Cronbach's alpha, and convergent validity. RESULTS: Data from a total of 404 Chinese adults (60.0% female) who had completed the Chinese NRSS were gathered. All items were invariant by gender. A 6-item version was obtained beyond which the test performance substantially deteriorated, and a 9-item version was obtained by OTA. The 9-item version performed better than the 6-item version in test information and convergent validity. It had discrimination and difficulty indices ranging from 0.44 to 2.23 and - 7.58 to 2.13, respectively, and retained 92% of the test information of the original 12-item version. CONCLUSION: The 9-item Chinese NRSS is a reliable and valid tool to measure nonrestorative sleep for epidemiological studies.

Health system responsiveness in Hong Kong: a comparison between South Asian and Chinese patients' experiences.

OBJECTIVES: Health system responsiveness is related to the way and the environment in which individuals are treated during their health system interaction. Generally, patients who are members of ethnic minority (EM) groups encounter more challenges in receiving healthcare services and bear a disproportionate burden of diseases compared with most counterparts. We aimed to compare the health system responsiveness perceived by South Asian (SA) EM people with that of local Chinese people in Hong Kong. STUDY DESIGN: The cross-sectional survey sample comprised 575 SA and 494 Chinese individuals. The health system responsiveness module of the World Health Survey 2002 was used for data collection. METHODS: We used propensity score weighting method to balance the two groups. Simple and multiple regressions were used to compare the perceived outpatient and inpatient health system responsiveness between SA and Chinese participants, respectively, before and after adjustment for demographics. All estimates were accompanied by 95% confidence intervals, and two-sided tests were conducted with significance concluded by a P value < 0∙05. RESULTS: Compared with the Chinese participants, the SA participants reported generally lower health system responsiveness for outpatient and inpatient services. The top three mean score difference (SA-Chinese) for outpatient care included autonomy (-0.78, P < 0.001), communication (-0.67, P < 0.001), and choice (-0.53, P < 0.001), and the top three mean score difference for inpatient care included communication (-0.90, P < 0.001), autonomy (-0.82, P < 0.001), and choice (-0.61, P < 0.01). In addition, SA participants also experienced lower responsiveness in access to community support (-0.81, P < 0.001) during hospitalization but perceived higher quality of basic amenities (0.29, P < 0.001) and confidentiality (0.44, P < 0.01) in outpatient settings. CONCLUSION: SA participants in an urbanized Chinese-oriented society reported generally lower health system responsiveness compared with the local Chinese group; however, SA participants perceived higher confidentiality and quality of basic amenities in their outpatient experience. Concerted efforts from healthcare providers and policymakers are required to improve the existing healthcare system for users of members of EM groups.

Nonrestorative sleep scale: reliable and valid for the Chinese population.

PURPOSE: To conduct a linguistic and psychometric evaluation of a Chinese version of the Nonrestorative Sleep Scale (NRSS). METHODS: The Chinese NRSS was created from a standard forward-backward translation and trialed on 10 Chinese adults. Telephone interviews were then conducted with 100 adults, who completed the Chinese NRSS, the Pittsburgh Sleep Quality Index (PSQI), the Athens Insomnia Scale (AIS), the Center for Epidemiological Studies Depression Scale (CES-D), and the Toronto Hospital Alertness Test (THAT). A household survey was conducted with 20 subjects, followed by a confirmatory factor analysis (CFA), and a bifactor model was developed to evaluate the reliability and validity of the NRSS. RESULTS: The bifactor model had the root mean square error of approximation (RMSEA), standardized root mean square residual (SRMR), and comparative fit index (CFI) of 0.06, 0.06, and 0.97, respectively. Convergent validity was shown from the moderate associations with PSQI (r = - 0.66, P < 0.01), AIS (r = - 0.65, P < 0.01), CES-D (r = - 0.54, P < 0.01), and THAT (r = 0.68, P < 0.01). The coefficient omega (0.92), omega hierarchical (0.81), factor determinacy (0.93), H value (0.91), explained common variance (0.63), and percentage of uncontaminated correlations (0.80) derived from the bifactor CFA supported the essential unidimensionality of NRSS. CONCLUSIONS: The Chinese NRSS is a valid and reliable essential unidimensional tool for the assessment of nonrestorative sleep in the Chinese population.

Meteorological factors to fall: a systematic review.

There existed systematic review on studies investigating the association between hip fractures and external risk factors including meteorological factors. Albeit the fact that most serious common fall injury is a hip fracture, it cannot account for all injuries forms of fall. There was a lack of systematic review covering all fall-related injury or deaths to thoroughly summarise meteorological aspects of fall. This study aimed to systematically review epidemiological studies of fall and fall-related circumstances without restriction to hip fracture. A systematic search in three databases, namely PubMed, CINAHL Plus and EMBASE, was performed. Searches in two Chinese databases named the Wanfang Med Online and the China Journal Net were done in addition. A total of 29 studies were identified. The study site, fall cases identification, meteorological factors and findings of all the selected studies were being extracted. The quality of the studies was critically appraised. We identified some of the environmental risk factors to fall among those studies. Ranging from the lower ambient temperature, the presence of snow cover, seasonal factors, and time of the day to location of fall, these factors have different levels of impact related to higher incidence or mortality of fall. To conclude, a better understanding of injury mechanisms is a prerequisite for preventive interventions.

The use of social networking applications of smartphone and associated sexual risks in lesbian, gay, bisexual, and transgender populations: a systematic review.

The use of social networking applications (apps) on smartphones has the potential to impact sexual health and behaviour. This was the first systematic review to critically appraise and summarize the existing literature on the use of social networking apps on smartphones and their associated sexual health and sexual behaviour effects in lesbian, gay, bisexual and transgender populations. A systematic search was conducted in five databases (CINAHL Plus, PsycINFO, PubMed, SCOPUS and Sociological Abstracts), using controlled terms and keywords. Thirteen articles from 11 studies were included in this review. Studied outcomes included rates of unprotected sexual intercourse, the number of sexual partners, drug/alcohol use prior to/during sexual intercourse, sexually transmitted infections (STIs) testing and the prevalence of STIs. Among app users, the prevalence of unprotected sex ranged from 17.0% to 66.7%. The mean number of sexual partners ranged from 1.4 to 2.9 (last 1-month period), and from 46.2 to 79.6 (lifetime). Two studies found that the prevalence of HIV infection was 1.9% and 11.4%, respectively. The self-reported prevalence of prior diagnosis of STIs other than HIV ranged from 9.1% to 51.0%. It should be noted that the heterogeneity of the study design and outcome measures across different studies hindered the comparison of findings across different studies. Furthermore, the findings in some studies are not reliable due to methodological problems. Our results highlight the need for more research with rigorous methodology to understand the negative impacts of using these apps on sexual health and sexual behaviour. For future studies, the operational definition of outcomes, including social networking app use and unprotected anal intercourse (UAI), should be clearly outlined. The use of validated tools to measure sexual behaviour and biological measures of HIV and other STDs is preferable so that outcomes can be standardized to facilitate comparisons between studies and the pooling of data.

Real-time estimation of the hospitalization fatality risk of influenza A(H1N1)pdm09 in Hong Kong.

During the early stage of an epidemic, timely and reliable estimation of the severity of infections are important for predicting the impact that the influenza viruses will have in the population. We obtained age-specific deaths and hospitalizations for patients with laboratory-confirmed H1N1pdm09 infections from June 2009 to December 2009 in Hong Kong. We retrospectively obtained the real-time estimates of the hospitalization fatality risk (HFR), using crude estimation or allowing for right-censoring for final status in some patients. Models accounting for right-censoring performed better than models without adjustments. The risk of deaths in hospitalized patients with confirmed H1N1pdm09 increased with age. Reliable estimates of the HFR could be obtained before the peak of the first wave of H1N1pdm09 in young and middle-aged adults but after the peak in the elderly. In the next influenza pandemic, timely estimation of the HFR will contribute to risk assessment and disease control.

Assessment of the severity of Ebola virus disease in Sierra Leone in 2014-2015.

The current Ebola virus disease (EVD) epidemic in West Africa is unprecedented in scale, and Sierra Leone is the most severely affected country. The case fatality risk (CFR) and hospitalization fatality risk (HFR) were used to characterize the severity of infections in confirmed and probable EVD cases in Sierra Leone. Proportional hazards regression models were used to investigate factors associated with the risk of death in EVD cases. In total, there were 17 318 EVD cases reported in Sierra Leone from 23 May 2014 to 31 January 2015. Of the probable and confirmed EVD cases with a reported final outcome, a total of 2536 deaths and 886 recoveries were reported. CFR and HFR estimates were 74·2% [95% credibility interval (CrI) 72·6-75·5] and 68·9% (95% CrI 66·2-71·6), respectively. Risks of death were higher in the youngest (0-4 years) and oldest (⩾60 years) age groups, and in the calendar month of October 2014. Sex and occupational status did not significantly affect the mortality of EVD. The CFR and HFR estimates of EVD were very high in Sierra Leone.

Automated otolith image classification with multiple views: an evaluation on Sciaenidae.

Combined multiple 2D views (proximal, anterior and ventral aspects) of the sagittal otolith are proposed here as a method to capture shape information for fish classification. Classification performance of single view compared with combined 2D views show improved classification accuracy of the latter, for nine species of Sciaenidae. The effects of shape description methods (shape indices, Procrustes analysis and elliptical Fourier analysis) on classification performance were evaluated. Procrustes analysis and elliptical Fourier analysis perform better than shape indices when single view is considered, but all perform equally well with combined views. A generic content-based image retrieval (CBIR) system that ranks dissimilarity (Procrustes distance) of otolith images was built to search query images without the need for detailed information of side (left or right), aspect (proximal or distal) and direction (positive or negative) of the otolith. Methods for the development of this automated classification system are discussed.

Successful Semi-Ambulatory Veno-Arterial Extracorporeal Membrane Oxygenation Bridge to Heart-Lung Transplantation in a Very Small Child.

Lung transplantation (LTx) may be denied for children on extracorporeal membrane oxygenation (ECMO) due to high risk of cerebral hemorrhage. Rarely has successful LTx been reported in children over 10 years of age receiving awake or ambulatory veno-venous ECMO. LTx following support with ambulatory veno-arterial ECMO (VA ECMO) in children has never been reported to our knowledge. We present the case of a 4-year-old, 12-kg child with heritable pulmonary artery hypertension and refractory right ventricular failure. She was successfully bridged to heart-lung transplantation (HLTx) using ambulatory VA ECMO. Initial resuscitation with standard VA ECMO was converted to an ambulatory circuit using Berlin heart cannulae. She was extubated and ambulating around her bed while on VA ECMO for 40 days. She received an HLTx from an oversized marginal lung donor. Despite a cardiac arrest and Grade 3 primary graft dysfunction, she made a full recovery without neurological deficits. She achieved 104% force expiratory volume in 1 s 33 months post-HLTx. Ambulatory VA ECMO may be a useful strategy to bridge very young children to LTx or HLTx. Patient tailored ECMO cannulation, minimization of hemorrhage, and thrombosis risks while on ECMO contributed to a successful HLTx in our patient.

Analysis of potential changes in seriousness of influenza A and B viruses in Hong Kong from 2001 to 2011.

Continued monitoring of the seriousness of influenza viruses is a public health priority. We applied time-series regression models to data on cardio-respiratory mortality rates in Hong Kong from 2001 to 2011. We used surveillance data on outpatient consultations for influenza-like illness, and laboratory detections of influenza types/subtypes to construct proxy measures of influenza activity. In the model we allowed the regression coefficients for influenza to drift over time, and adjusted for temperature and humidity. The regression coefficient for influenza A(H3N2) increased significantly in 2005. The regression coefficients for influenza A(H1N1) and B were relatively stable over the period. Our model suggested an increase in seriousness of A(H3N2) in 2005, the year after the appearance of the A/Fujian/411/2002(H3N2)-like virus when the drifted A/California/7/2004(H3N2)-like virus appeared. Ongoing monitoring of mortality and influenza activity could permit identification of future changes in seriousness of influenza virus infections.

Successful lung transplant in a child with cystic fibrosis and persistent Blastobotrys rhaffinosifermentans infection.

Fungal respiratory infections in patients with CF are a significant concern both pre- and post-lung transplantation (LTx). Fungal infection is associated with increased mortality post-LTx, and in the past decade, the prevalence of fungal colonization in Canadian pediatric patients with CF has increased. The emergence of novel fungal pathogens is particularly challenging to the transplant community, as little is known regarding their virulence and optimal management. We present a case of a successful double-lung transplant in a pediatric patient with CF who was infected pretransplantation with a novel yeast, Blastobotrys rhaffinosifermentans. This patient was treated successfully with aggressive antifungal therapy post-transplantation, followed by extended fungal prophylaxis. The significance of fungal colonization and infection in children with CF pre- and post-LTx is reviewed.

Telomere length and early severe social deprivation: linking early adversity and cellular aging.

Accelerated telomere length attrition has been associated with psychological stress and early adversity in adults; however, no studies have examined whether telomere length in childhood is associated with early experiences. The Bucharest Early Intervention Project is a unique randomized controlled trial of foster care placement compared with continued care in institutions. As a result of the study design, participants were exposed to a quantified range of time in institutional care, and represented an ideal population in which to examine the association between a specific early adversity, institutional care and telomere length. We examined the association between average relative telomere length, telomere repeat copy number to single gene copy number (T/S) ratio and exposure to institutional care quantified as the percent of time at baseline (mean age 22 months) and at 54 months of age that each child lived in the institution. A significant negative correlation between T/S ratio and percentage of time was observed. Children with greater exposure to institutional care had significantly shorter relative telomere length in middle childhood. Gender modified this main effect. The percentage of time in institutional care at baseline significantly predicted telomere length in females, whereas the percentage of institutional care at 54 months was strongly predictive of telomere length in males. This is the first study to demonstrate an association between telomere length and institutionalization, the first study to find an association between adversity and telomere length in children, and contributes to the growing literature linking telomere length and early adversity.

Preliminary inferences on the age-specific seriousness of human disease caused by avian influenza A(H7N9) infections in China, March to April 2013.

Between 31 March and 21 April 2013, 102 laboratory-confirmed influenza A(H7N9) infections have been reported in six provinces of China. Using survey data on age-specific rates of exposure to live poultry in China, we estimated that risk of serious illness after infection is 5.1 times higher in persons 65 years and older versus younger ages. Our results suggest that many unidentified mild influenza A(H7N9) infections may have occurred, with a lower bound of 210­550 infections to date.

Paternal age at birth is associated with offspring leukocyte telomere length in the nurses' health study.

STUDY QUESTION: Is the association between paternal age at birth and offspring leukocyte telomere length (LTL) an artifact of early life socioeconomic status (SES)? SUMMARY ANSWER: Indicators of early life SES did not alter the relationship between paternal age at birth and offspring LTL among a population of white female nurses. WHAT IS KNOWN ALREADY: Telomere length is considered a highly heritable trait. Recent studies report a positive correlation between paternal age at birth and offspring LTL. Maternal age at birth has also been positively associated with offspring LTL, but may stem from the strong correlation with paternal age at birth. STUDY DESIGN, SIZE AND DURATION: The Nurses' Health Study (NHS) is an ongoing prospective cohort study of 121 700 female registered nurses who were enrolled in 1976. Great effort goes into maintaining a high degree of follow-up among our cohort participants (>95% of potential person-years). In 1989-1990, a subset of 32 826 women provided blood samples from which we selected participants for several nested case-control studies of telomere length and incident chronic disease. We used existing LTL data on a total of 4250 disease-free women who also reported maternal and paternal age at birth for this study. PARTICIPANTS/MATERIALS, SETTING AND METHODS: Nested case-control studies of stroke, myocardial infarction, cancers of the breast, endometrium, skin, pancreas and colon, as well as colon adenoma, were conducted within the blood sub-cohort. Each study used the following study design: for each case of a disease diagnosed after blood collection, a risk-set sampling scheme was used to select from one to three controls from the remaining participants in the blood sub-cohort who were free of that disease when the case was diagnosed. Controls were matched to cases by age at blood collection (± 1 year), date of blood collection (± 3 months), menopausal status, recent postmenopausal hormone use at blood collection (within 3 months, except for the myocardial infarction case-control study), as well as other factors carefully chosen for each individual study. The current analysis was limited to healthy controls. We also included existing LTL data from a small random sample of women participating in a cognitive sub-study. LTL was measured using the quantitative PCR-based method. Exposure and covariate information are extracted from biennial questionnaires completed by the participants. MAIN RESULTS AND THE ROLE OF CHANCE: We found a strong association between paternal age at birth and participant LTL (P = 1.6 × 10(-5)) that remained robust after controlling for indicators of early life SES. Maternal age at birth showed a weak inverse association with participant LTL after adjusting for age at blood collection and paternal age at birth (P = 0.01). We also noted a stronger association between paternal age at birth and participant LTL among premenopausal than among postmenopausal women (P(interaction) = 0.045). However, this observation may be due to chance as premenopausal women represented only 12.6% (N = 535) of the study population and LTL was not correlated with age at menopause, total or estrogen-only hormone therapy (HT) use suggesting that changes in in vivo estrogen exposure do not influence telomere length regulation. LIMITATIONS AND REASONS FOR CAUTION: The women in our study are not representative of the general US female population, with an underrepresentation of non-white and low social class groups. Although the interaction was not significant, we noted that the paternal age at birth association with offspring LTL appeared weaker among women whose parents did not own their home at the time of the participant's birth. As telomere dynamics may differ among individuals who are most socioeconomically deprived, SES indicators may have more of an influence on the relationship between paternal age at birth and offspring LTL in such populations. WIDER IMPLICATIONS OF THE FINDINGS: As of yet, our and prior studies have not identified childhood or adult characteristics that confound the paternal age at birth association with offspring LTL, supporting the hypothesis that offspring may inherit the longer telomeres found in sperm of older men. The biological implications of the paternal age effect are unknown. A recent theory proposed that the inheritance of longer telomere from older men may be an adaptive signal of reproductive lifespan, while another theory links telomere length attrition to female reproductive senescence. However, we are unaware of any data to substantiate a relationship between paternal age at birth and daughter's fertility. Generalizability of our study results to other white female populations is supported by prior reports of paternal age at birth and offspring telomere length. Furthermore, a confounding relationship between paternal or maternal age at birth and SES was not observed in a study of SES and telomere length. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Institutes of Health (grants numbers: CA87969, CA49449, CA065725, CA132190, CA139586, HL088521, CA140790, CA133914, CA132175, ES01664 to M.D.); and by the American Health Association Foundation. We have no competing interests to declare.

Endoscopic submucosal dissection of gastric lesions by using a master and slave transluminal endoscopic robot: an animal survival study.

BACKGROUND AND STUDY AIMS: The feasibility of performing endoscopic submucosal dissection (ESD) using the Master and Slave Transluminal Endoscopic Robot (MASTER), a robotics-enhanced surgical system, has been shown in our previous study. This study aimed to further explore, in an animal survival study, the 2-week outcome of using MASTER to perform ESD. PATIENTS AND METHODS: In this prospective study, ESD was performed on five female pigs (weighing 32.4 - 36.8 kg) under general anesthesia using the MASTER. The animals were observed for 2 weeks before being humanely killed for necropsy examination. The main outcome measures were completeness of resection, procedure-related complications, and survival at 2 weeks. RESULTS: The procedure was successfully completed in all five pigs. It took a mean of 21.8 minutes (range 6 - 39 minutes) to complete the ESD of each gastric lesion. All lesions were excised en bloc; the average dimension of the lesions was 77 mm (range 25 - 104 mm). One pig sustained a small intraoperative perforation which was identified and successfully clipped. After completion of the ESD procedures, all pigs survived well for 2 weeks. Necropsy was performed, with intraoperative gastroscopy identifying all the ESD sites as healed. Histopathologic examination showed all ESD sites had healed with partial epithelialization. Microbiological tests of the peritoneal fluid showed only microbes typically found in pigs. CONCLUSION: Performing ESD with MASTER was feasible and safe in this 2-week animal survival study.

Interobserver reliability in the endoscopic diagnosis and grading of Barrett's esophagus: an Asian multinational study.

BACKGROUND AND STUDY AIM: The establishment of precise and valid diagnostic criteria is important for any disease. We determined the interobserver reliability in the endoscopic diagnosis and grading of Barrett's esophagus. PATIENTS AND METHODS: Video clips of endoscopy in 21 patients with/without Barrett's esophagus were used for training (n = 3) and for diagnosis/grading (n = 18) of Barrett's esophagus by endoscopists from seven hospitals in Asia. Barrett's esophagus was graded using the Prague C & M Criteria whereby the circumferential extent of the Barrett's segment (C value), maximum extent of Barrett's segment (M value), location of the gastroesophageal junction, and location of the diaphragmatic hiatus were scored. The intraclass correlation coefficients (ICC) were calculated as a measure of interobserver reliability. RESULTS: A total of 34 endoscopists participated. ICC values for the scores of the C value, M value, location of the gastroesophageal junction, and location of the diaphragmatic hiatus were: 0.92 (95 % confidence interval [CI] 0.88 - 0.97), 0.94 (95 %CI 0.90 - 0.98), 0.86 (95 %CI 0.78 - 0.94), and 0.81 (95 %CI 0.71 - 0.92), respectively, indicating excellent interobserver agreement. The differences in region/country, endoscopists' experience, case volume of participating centers, or primary practice type had no significant effect on the reliability. The ICC values for recognition of Barrett's esophagus of > or = 1 cm were 0.90 (95 %CI 0.80 - 1.00) and 0.92 (95 %CI 0.87 - 0.98) for the C and M values, respectively, whereas the corresponding ICC values for Barrett's segment of < 1 cm were 0.18 (95 %CI 0.03 - 0.32) and 0.21 (95 %CI 0.00 - 0.51), respectively. CONCLUSIONS: Despite the uncommon occurrence of Barrett's esophagus in Asia, our endoscopists exhibited excellent agreement in the endoscopic diagnosis and grading of Barrett's esophagus using the Prague C & M Criteria. However, in view of the low interobserver reliability in recognizing Barrett's segments of < 1 cm, future studies in Asia should take this into account when selecting the study population.