Age
Longitudinal physical activity and sedentary behavior in preschool-aged children with cerebral palsy across all functional levels
This study had three aims: to describe habitual physical activity and sedentary behavior in young children with cerebral palsy (CP) from 1 year 6 months to 5 years of age, to compare habitual physical activity between time points, and to examine the rate of change in habitual physical activity and sedentary behavior across all gross motor functional capabilities.
The study sample was drawn from two population-based cohort studies conducted in Queensland, Australia. Eligible children were born between 2006 and 2009 and diagnosed with CP by a physician; and for this study, children had to have completed 3-day physical activity monitoring at any of the follow-up time points in the cohort studies (at 18 months – 2 years, 2 years 6 months – 3 years, 4 years, and 5 years of age).
Study participants were classified for gross motor function at each follow-up visit. Physical activity was measured using an accelerometer worn for 3 days, and with an activity diary kept by parents. The authors used a linear mixed-effects model to assess the association between physical activity and gross motor functional capabilities. This model was chosen to account for non-independence of repeated measures on the same participants.
http://onlinelibrary.wiley.com.ucsf.idm.oclc.org/doi/10.1111/dmcn.13439/abstract
Time Since Study Enrollment
Substance use patterns and factors associated with changes over time in a cohort of heterosexual women at risk for HIV acquisition in the United States
The aim of this study was to analyze substance use patterns in a large, geographically diverse cohort of women at increased risk for HIV infection.
The study sample is a multisite, longitudinal cohort of women at elevated risk of HIV infection. Eligible women were enrolled in 2009 and 2010 from 10 urban and peri-urban communities in six geographic regions of the US. Women were recruited during randomly selected venue-time intervals within each community (e.g. women entering the venue during a recruitment interval were approached for screening), and included if they reported unprotected sex with a man in the previous six months and at least one other personal or partner HIV risk characteristic.
Women meeting the inclusion criteria (for this analysis, all women reporting substance use at baseline were included) were followed at 6-month intervals for either 6 or 12 months. Self-reported substance use (drug use and/or binge drinking) in the past six months was assessed by type of substance and frequency. The association between substance use (specifically decreased substance use between baseline and the follow-up visit) and baseline predictors of substance use was assessed by bivariate and multivariate log regression (is this the same as logistic regression?).
Other Time Dimension
Radiation effects on cognitive function among atomic bomb survivors exposed at or after adolescence
The aim of this study was to investigate the effects of radiation on pre-dementia cognitive decline among participants who did and did not develop dementia during follow-up.
The study population consisted of participants in the original Adult Health Study cohort consisting of atomic bomb survivors who were within a set distance of the Hiroshima atomic bomb, and age- and sex-matched subjects who were beyond a set distance to the same, and who were >= 60 years of age in 1992. Participants from the cohort were included if they did not meet a set of exclusion criteria based on completeness of data, age, and timing of dementia onset.
Participants were followed every two years, and cognitive function was assessed at baseline using the Cognitive Abilities Screening Instrument (CASI) and thereafter using a short version of the CASI at each follow-up visit. Dementia was assessed for using criteria in the DSM, 4th edition. Radiation dose was estimated using the Dosimetry System 2002. The authors used a random coefficient regression model to estimate the association between radiation exposure and cognitive decline and cognition level in both demented and cognitively intact individuals.
http://www.sciencedirect.com.ucsf.idm.oclc.org/science/article/pii/S0002934315009109