

Randomization at the provider level, with each provider coaching only one of the strategies, would reduce the risk of contamination. Some participants in each group might even adopt elements of both strategies, and neither group would demonstrate the impact of its intended strategy.
Define collaboratory trial#

There are also compelling practical reasons for randomizing clusters rather than individuals ( Cook et al 2016). (See also "What Is Contamination, and Why Does it Matter?" immediately below). Contamination occurs when aspects of an intervention are adopted by members of the group that was randomized to not receive that intervention. Second, a CRT might be preferred when there is a significant potential for contamination in the study. For example, while a traditional RCT may be better suited to determining whether a novel therapy works in patients with a given disease or condition, a CRT is better able to evaluate whether a new standard of care, guideline recommendation, or other practice-wide, hospital-wide, or system-wide change is affecting patient outcomes. First, a CRT might be preferred when the target of the intervention is a collective or system rather than a particular person, such as a patient. There are several reasons why CRT designs might be preferred to or more suitable than a traditional RCT. Watch the video module: Understanding Clustering in Cluster Randomized Trials CRTs are in common use in areas such as education and public health research they are particularly well suited to testing differences in a method or approach to patient care (as opposed to evaluating the physiological effects of a specific intervention). Cluster randomized trials (CRTs) differ from individually randomized RCTs in that the unit of randomization is something other than the individual participant or patient.
