INTRODUCTION: Randomization is the most optimal design for evaluating program-effectiveness. In practice, however, conducting a randomized controlled trial is not always feasible. For a non-randomized...
BACKGROUND: The approximately 1100 medical journals now active in China are publishing a rapidly increasing number of research reports, including many studies identified by their authors as randomized...
Drawing inferences on a causal relationship between a particular intervention and the observed outcome requires to conduct a clinical experiment which controls for study conditions and systematic erro...
In clinical research, randomized trials are widely accepted as the definitive method of evaluating the efficacy of therapies. Random assignment of patients to treatment ensures internal validity of th...
During the design phase of any research, an investigator addresses internal and external threats to validity and develops mechanisms to minimize these threats. Controlling for threats to study validit...
Randomized lard and butter oil were conpared with native lard and butter oil for their effects on cholesterol-induced atherosclerosis in rabbits. In each experiment there was also a group fed corn oil...