Effectiveness of the 'SELF-program' on nurses' activity encouragement behavior and nursing home resident's ADL self-reliance; a cluster-randomized trial.

Background: Nurses play a crucial role in encouraging nursing home resident's activity and independent functioning. However, nurses often take over tasks unnecessarily, which can deprive resident's remaining abilities. The Function-Focused Care philosophy offers guidance for developing programs that support nurses to optimize activity and independence of older people.

Young children's performance on a design fluency task: longitudinal data on total number of designs, clustering and switching, and regression-based norms.

Introduction: Design fluency (DF) tasks are commonly used to assess executive functions such as attentional control, cognitive flexibility, self-monitoring and strategy use. Next to the total number of correct designs, the standard outcome of a DF task, clustering and switching can help disentangle the processes underlying DF performance. We present the first longitudinal study of 4-8-year-old children's developmental DF trajectories.

Cluster Randomized Trials with a Pretest and Posttest: Equivalence of Three-, Two- and One-Level Analyses, and Sample Size Calculation.

In a cluster randomized trial clusters of persons, for instance, schools or health centers, are assigned to treatments, and all persons in the same cluster get the same treatment. Although less powerful than individual randomization, cluster randomization is a good alternative if individual randomization is impossible or leads to severe treatment contamination (carry-over). Focusing on cluster randomized trials with a pretest and post-test of a quantitative outcome, this paper shows the equivalence of four methods of analysis: a three-level mixed (multilevel) regression for repeated measures with as levels cluster, person, and time, and allowing for unstructured between-cluster and within-cluster covariance matrices; a two-level mixed regression with as levels cluster and person, using change from baseline as outcome; a two-level mixed regression with as levels cluster and time, using cluster means as data; a one-level analysis of cluster means of change from baseline.

Best (but oft forgotten) practices: Efficient sample sizes for commonly used trial designs.

Designing studies such that they have a high level of power to detect an effect or association of interest is an important tool to improve the quality and reproducibility of findings from such studies. Since resources (research subjects, time, and money) are scarce, it is important to obtain sufficient power with minimum use of such resources. For commonly used randomized trials of the treatment effect on a continuous outcome, designs are presented that minimize the number of subjects or the amount of research budget when aiming for a desired power level.