This paper assesses the options available to researchers analysing multilevel (including
longitudinal) data, with the aim of supporting good methodological decision-making. Given …

Multiple imputation is a tool for parameter estimation and inference with partially observed
data, which is used increasingly widely in medical and social research. When the data to be …

Background Quantifying changes in the levels of biological and cognitive markers prior to
the clinical presentation of Alzheimer's disease (AD) will provide a template for …

Physical activity provides multiple health benefits to seniors, and urban parks are one of
theprimary settings where seniors engage in physical activity. However, seniors' park-based …

Initiatives that promote mental well‐being are formally recommended for all British workers,
with many practices targeting change in individual workers' resources. While the existing …

Many datasets used in the social sciences have a hierarchical structure, where lower units of
aggregation are 'nested'in higher units. In many disciplines, such data are analyzed using …

This study evaluates the effectiveness of the KiVa antibullying program in the Netherlands
through a randomized controlled trial of students in grades 3–4 (Dutch grades 5–6). The …

Background/objectives Different genetic variants are associated with larger body size in
childhood vs adulthood. Whether and when these variants predominantly influence …

The ideal method of identifying frailty is uncertain, and data on long-term outcomes is
relatively limited. We examined frailty indices derived from population-scale linked data on …

Testing null hypotheses of the form “β= 0,” by the use of various Null Hypothesis
Significance Tests (rendering a dichotomous reject/not reject decision), is considered …