850 and .839, and .542 and .538, for perceived benefits and perceived barriers, respectively. Meanwhile, the Cronbach’s alpha was .857 and .859, and the intraclass correlation coefficient for test-retest reliability was .979 and .960 for perceived benefits and perceived barriers respectively. The findings provided evidence for measurement invariance of DB-M for the male and female samples. The final CFA model fit the data well for both male sample (CFI = .975, TLI = .964, SRMR = .040, RMSEA = .052) and female sample (CFI = .965, TLI = .949, SRMR = .044, RMSEA = .058). CONCLUSIONS The translated version of the DB-M was valid and reliable for assessing the level of perceived benefits and perceived barriers in exercise among university students in Malaysia.Prospective studies are key study designs when attempting to unravel health mechanisms that are widely applicable. Understanding the internal validity of a prospective study is essential to judge a study’s quality. Moreover, insights in possible sampling bias and the external validity of a prospective study are useful to judge the applicability of a study’s findings. SB203580 We evaluated participation, retention, and associated factors of women in a multicenter prospective cohort (FemCure) to understand the study’s validity.Chlamydia trachomatis (CT) infected adult women, negative for HIV, syphilis, and Neisseria gonorrhoeae were eligible to be preselected and included at three sexually transmitted infection (STI) clinics in the Netherlands (2016-2017). The planned follow-up for participants was 3 months, with two weekly rectal and vaginal CT self-sampling and online questionnaires administered at home and at the clinic. We calculated the proportions of preselected, included, and retained (completed follow-up) women. Associations with non-preselection, noninclusion, and non-retention (called attrition) were assessed (logistic and Cox regression).Among the 4,916 women, 1,763 (35.9%) were preselected, of whom 560 (31.8%) were included. The study population had diverse baseline characteristics study site, migration background, high education, and no STI history were associated with non-preselection and noninclusion. Retention was 76.3% (n = 427). Attrition was 10.71/100 person/month (95% confidence interval 9.97, 12.69) and was associated with young age and low education. In an outpatient clinical setting, it proved feasible to include and retain women in an intensive prospective cohort. External validity was limited as the study population was not representative (sampling bias), but this did not affect the internal validity. Selective attrition, however (potential selection bias), should be accounted for when interpreting the study results.In this study, two parasites on the fins of Homatula variegata were recorded from March to September 2016. A dissection mirror was used to examine the distribution and quantity of the ectoparasitic Gyrodactylus sp. and Paragyrodactylus variegatus on the host Homatula variegata in different seasons. The present study explored possible explanations for the site specificity of gyrodactylid parasites in 442 Homatula variegata infected with 4307 Gyrodactylus sp. (species identification is incomplete, only characterized to the genus level) and 1712 Paragyrodactylus variegatus. These two gyrodactylid parasites were collected from fish fins, and the fish were harvested in China’s Qinling Mountains.The results indicated that the highest number of Gyrodactylus sp., which was numerically the dominant species, appeared on the fish fins in April, while the highest number of Paragyrodactylus variegatus was found on the fish fins in March. The two parasite species appeared to be partitioned spatially, with Gyrodactylus sp. occurring more frequently on pectoral and pelvic fins, and P. variegatus occurring more frequently on caudal fins. However, Gyrodactylus sp. appeared to occur on fish of all lengths, while P. variegatus tended to occur more abundantly on shorter fish rather than on longer fish. At lower Gyrodactylus sp. infection levels ( less then 100), the pelvic and pectoral fins were the main locations of attachment, followed by the dorsal fin. For infections of more than 100 parasites, more samples of Gyrodactylus sp. were located on the pectoral fin. For a low number of Paragyrodactylus variegatus infections ( less then 100), the pelvic and pectoral fins were the preferred locations of attachment, followed by the caudal fin. Between April and September, there were many monogenean parasites on fish fins, and the fish size was within the range of 5-10 cm. However, when a fish was longer than 10 cm long, the number of parasites on its fins greatly decreased.OBJECTIVE Atrial fibrillation (AF) is associated with adverse outcomes in the general population, but its impact on patients with chronic kidney disease (CKD) remains unclear. In this study, we assessed the association between AF and risks of all-cause mortality and stroke in Chinese adults with CKD. METHODS We enrolled adults aged 45 years or older with CKD (defined as an estimated glomerular filtration rate less then 60 mL/min per 1.73 m2 and/or proteinuria identified using the urine dipstick method) from the Kailuan study between 2008 and 2014. AF was identified by 12-lead electrocardiography or hospital discharge diagnostic codes. Mortality data were collected from the provincial vital statistics, and physician-diagnosed ischemic or hemorrhagic stroke was confirmed in the biennial interview. RESULTS Among the 21587 CKD adults, 216 patients were identified with AF, the median follow-up duration was 5.21 years (5.69 ± 1.96 years); During follow-up, there were 70 cases of death, and 16 cases of ischemic stroke and 6 cases of hemorrhagic stroke in the participants with AF in comparison with 2572 cases of death and 656 cases of ischemic stroke and 184 cases of hemorrhagic stroke among the participants without AF. After adjustment for potential confounders, AF was associated with an 86% increase in the rate of death (hazard ratio [HR], 1.86; 95% confidence interval [CI], 1.33-2.59, P less then 0.001), a 104% (HR, 2.04; 95% CI, 1.09-3.83, P = 0.026) and 325% (HR, 4.25; 95% CI, 1.74-10.36, P = 0.001) increase in the rate of ischemic stroke and hemorrhagic stroke, respectively. These associations were still consistent and strong after propensity score-matched analysis. CONCLUSION Our study shows that AF is independently associated with increased risk of all-cause mortality, ischemic and hemorrhagic stroke in Chinese CKD adults. Future studies are required to elucidate the physiological mechanisms underlying this association.