Abbas F Jawad
University of Pennsylvania Prelem School of Medicine
and the Children’s Hospital of Philadelphia
USA
Title: Cluster randomization trials in schools setting: design and analysis
Biography
Biography: Abbas F Jawad
Abstract
Cluster randomization trials (CRT) are commonly used in the evaluation of non-theraputic interventions such improvement of educaiton programs, health educations and enovation in behavioral and enviromental improvement in schools and communities. Cluster as a unit of randomization varies in in sizes, It could be a housholds or families, entire communities, religious institution, hospitals units, classrooms. Unlike individually randomized trials, CRT can measure the interventions efect on a targetted group of individuals. However, it prones to be less efficient and weaker statistical power, hence requires more clusters. During the past two decade, CRT designs and methodology has been intensely improved, although scattered, it cover a wide range of applications. Fisher’s thoery of experiemtal desing assumed that the randomization unit is the same unit of analysis. The uniqness of CRT is that the randomization unit is the clusters, and the analysis target clusters’ the members. In school setting,measurements obtianed from students within a school are expected to be more correlated than measurments obtianed from students in a different schools, similarly, for classes within schools. Such correlation should be accounted for during the statistical analysis stage. Another source of chalanges are related to the collaboration of the gatekeepers and stakeholdre in these schools, consisitnacy reliability of tools used, consistency among therapists, teachers. Also, seasonal effects as well as uncontroled school ‘schanges related to personnels and budget cutting. CTR require approval of the athical committees desgniated witin schools, which requires better understanding of study design since gatekeepers can’t consent on behalf of stdents.