The positive deviance approach: challenges and opportunities for the future.

The positive deviance (PD) approach offers an alternative to needs-based approaches for development. The "traditional" application of the PD approach for childhood malnutrition involves studying children who grow well despite adversity, identifying uncommon, model practices among PD families, and designing an intervention to transfer these behaviors to the mothers of malnourished children. A common intervention for child malnutrition, the so-called "hearth," brings mothers together to practice new feeding and caring behaviors under the encouragement of a village volunteer. Hearths probably work because they modify unmeasured behavioral determinants and unmonitored behaviors, which, in turn, result in better child growth. Some health outcomes require a better understanding of behavioral determinants and are not best served by hearth-like facilitated group skills-building. We propose testing "booster PD inquiries" during implementation to confirm behavioral determinants and efficiently focus interventions. We share early experience with the PD approach for HIV/AIDS and food security. The attributable benefit of the PD approach within a program has not been quantified, but we suspect that it is a catalyst that accelerates change through the processes of community attention getting, awareness raising, problem-solving, motivating for behavior change, advocacy, and actual adopting new behaviors. Program-learners should consider identifying and explicitly attempting to modify the determinants of critical behavior(s), even if the desired outcome is a change in health status that depends on multiple behaviors; measure and maintain program quality, especially at scale; and creatively expand and test additional roles for PD within a given program.