Cluster randomized trials CRTs have undeniable strengths, but also complications. This paper addresses the logistical challenges of achieving methodological 'best practice' in CRTs, drawing on the experience of implementing a CRT within a running community-based health insurance CBHI scheme in Gujarat, India.
Our CRT is seeking to improve the equity impact - i.e. reduce the differential in claims submission for hospitalization between poor and less poor - of this CBHI in rural areas.
Six main challenges are identified and discussed:
- assigning control clusters;
- implementing multiple interventions simultaneously across twelve sub-districts;
- minimizing leakage across intervention groups;
- piggy-backing on a continually changing scheme;
- designing interventions that are financially and administratively sustainable.
The challenges identified are not likely to be unique to low-income settings, although the last two issues are particularly likely when working with relatively small and resource-constrained programmes. While compromises to methodological best-practice may reduce internal validity, they make the intervention more 'real', and potentially more applicable, to other programmes and settings.
Canadian Journal of Public Health (2006) 97 (1) 72-75