African Americans patients were less likely to use telehealth than other races, and utilization of telehealth did not improve their no show rate unlike patients from other racial backgrounds.
Analysts often use different conceptual definitions of a cohort effect, and therefore different statistical methods, which lead to differing empirical results. A definition often used in sociology ...assumes that cohorts have unique characteristics confounded by age and period effects, whereas epidemiologists often conceive that period and age effects interact to produce cohort effects. The present study aims to illustrate these differences by estimating age, period, and cohort (APC) effects on obesity prevalence in the U.S. from 1971 to 2006 using both conceptual approaches. Data were drawn from seven cross-sectional waves of the National Health and Nutrition Examination Survey. Obesity was defined as BMI
≥
30 for adults and ≥95th percentile for children under the age of 20. APC effects were estimated using the classic constraint-based method (first-order effects estimated and interpreted), the Holford method (first-order effects estimated but second-order effects interpreted), and median polish method (second-order effects are estimated and interpreted). Results indicated that all methods report significant age and period effects, with lower obesity prevalence in early life as well as increasing prevalence in successive surveys. Positive cohort effects for more recently born cohorts emerged based on the constraint-based model; when cohort effects were considered second-order estimates, no significant effects emerged. First-order estimates of age–period–cohort effects are often criticized because of their reliance on arbitrary constraints, but may be conceptually meaningful for sociological research questions. Second-order estimates are statistically estimable and produce conceptually meaningful results for epidemiological research questions. Age–period–cohort analysts should explicitly state the definition of a cohort effect under consideration. Our analyses suggest that the prevalence of obesity in the U.S. in the latter part of the 20th century rose across all birth cohorts, in the manner expected based on estimated age and period effects. As such, the absence or presence of cohort effects depends on the conceptual definition and therefore statistical method used.
The China birth cohort study (CBCS) Yue, Wentao; Zhang, Enjie; Liu, Ruixia ...
European journal of epidemiology,
03/2022, Letnik:
37, Številka:
3
Journal Article
Recenzirano
Odprti dostop
The China birth cohort study (CBCS) is a prospective longitudinal, mega-cohort study and the first national-based birth cohort study, aiming to establish a birth cohort covering representative ...geographical areas of the whole of China to investigate risk factors for birth defects and develop strategies for their reduction. Pregnant women who are of Chinese nationality, are 6–13
+6
weeks of gestation, plan to attend the routine antenatal examination and deliver in the study site, and give their informed, written consent are eligible to participate in this study. All participants are followed-up through an in-person interview at 20–23
+6
weeks and again at 28–33
+6
weeks of gestation, and at delivery, respectively. CBCS has been divided into three phases from 20th November 2017 to 31st December 2021, and the first two phases have now been completed on 29th February 2020, enrolling 120 377 eligible pregnant women during this period. During the same period a total of 40 837 participants had been followed up to the end of pregnancy. Study recruitment will continue until December 2021 to achieve the target of 500 000 participants. Meanwhile, biological samples including peripheral blood, amniocytes, cord blood, placenta, or umbilical cord tissue have been collected from participants according to various conditions. The incidence of birth defects in this group is 2.5% and congenital heart disease is the most common type of birth defect seen so far. A website is in the advanced stages of planning, to allow seamless data transfer and facilitate collaboration with groups around the world.
BackgroundQ-Motor assessments have been used in a number of large multicenter clinical studies in Huntington’s disease and beyond. Q-Motor has proven to be a robust and sensitive tool to track and ...compare motor performance cross-sectionally or longitudinally, reducing placebo effects and rater bias compared to clinical scales.AimsThe current study investigated whether the application of Q-Motor assessments in a large population-based sample is feasible, and whether it provides the opportunity to generate normative data and to investigate the effects of demographic variables on Q-Motor measures.MethodsThe BiDirect study is an observational, prospective cohort study conducted at the University of Muenster in Germany. All participants, including the population-based control cohort, performed the Q-Motor speeded tapping (digitomotography) and grasping & lifting (manumotography and choreomotography) tasks. Normative data was gathered with regard to age and sex, thereby considering further mediating variables. Effects were estimated using univariate multiple linear regression analyses.ResultsThe use of Q-Motor assessments was feasible in the setting of this longitudinal cohort study. Normative data was generated for all tasks applied and measures proposed. The applied models showed significant effects of age and sex on some tapping speed measures and involuntary movements: participants showed decreasing performance with increasing age. Moreover, women tended to tap slower than men, and the non-dominant hand showed reduced performance compared to the dominant hand across tests.ConclusionsQ-Motor assessments are feasible for population-based cohort studies. The normative data generated here will enable comparative analysis in other studies and clinical trials, including more robust conclusions about clinical change.
Background
During the past 25 years, many pregnancy and birth cohorts have been established. Each cohort provides unique opportunities for examining associations of early‐life exposures with child ...development and health. However, to fully exploit the large amount of available resources and to facilitate cross‐cohort collaboration, it is necessary to have accessible information on each cohort and its individual characteristics. The aim of this work was to provide an overview of European pregnancy and birth cohorts registered in a freely accessible database located at http://www.birthcohorts.net.
Methods
European pregnancy and birth cohorts initiated in 1980 or later with at least 300 mother–child pairs enrolled during pregnancy or at birth, and with postnatal data, were eligible for inclusion. Eligible cohorts were invited to provide information on the data and biological samples collected, as well as the timing of data collection.
Results
In total, 70 cohorts were identified. Of these, 56 fulfilled the inclusion criteria encompassing a total of more than 500 000 live‐born European children. The cohorts represented 19 countries with the majority of cohorts located in Northern and Western Europe. Some cohorts were general with multiple aims, whilst others focused on specific health or exposure‐related research questions.
Conclusion
This work demonstrates a great potential for cross‐cohort collaboration addressing important aspects of child health. The web site, http://www.birthcohorts.net, proved to be a useful tool for accessing information on European pregnancy and birth cohorts and their characteristics.
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