Should randomised controlled trials be the “gold standard” for research on preventive interventions for children?

Abstract

Should randomised controlled trials be the 'gold standard' for research on preventive interventions for children. Abstract (152 words)Randomised Controlled Trials (RCTs) have been offered a privileged position in terms of the evidence base for preventive interventions for children, but there are practical and theoretical issues that challenge this research methodology. Well recognised issues include the impossibility of blinding participants, the problem of identifying a pre-eminent outcome measure for complex interventions, and problems with limiting access to equivalent interventions in real world settings. A further theoretical problem is the exclusion from RCTs of families who are most ready to change, resulting in an apparently reduced level of intervention effectiveness. Qualitative evidence from a recent RCT suggests that this problem could be operating in some prevention trials. Increasing sample sizes can overcome some of these problems, but the cost of the necessarily huge trials becomes disproportionate to the low cost of preventive interview. Given the limitations on RCTs in preventive settings, their privileged position in terms of research evidence maybe undeserved. Summary of policy and practice implications (135)Policy makers and commissioners value certainty and RCTs are considered most likely to provide that certainty. In times of scare resources, interventions without an RCT evidence base are an easy target for cuts and/or decisions not to invest. In the context of preventive services for children this view is debatable. Because social, educational and public health interventions are complex and are offered in the context of a complex world, it is simplistic to believe that one research approach can provide all the necessary information on what works. A more sophisticated understanding of RCTs and complex interventions suggest that we should rebalance the hierarchy of evidence and give more credence to good studies of other designs. This might make policy makers and commissioners lives more complex and less certain, but it might improve outcomes for children. Category 2 Methodological Issues and DevelopmentsWord Count 3684

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