Executive summary

The term "positive deviance" has been used to describe the performance (regarding health, growth, and development) of certain children vis-à-vis the performance of other children in the community and the family. It has been seen as a form of social, behavioural, and physiological adaptability to nutritional stress.

From the perspective of young-child nutrition, positive deviants are children who grow and develop adequately in low-income families living in impoverished environments, where a majority of children suffer from growth retardation and malnutrition. A number of observers of this phenomenon, like Wray and Greaves, have called for greater attention to be given to this process of apparent adaptation so that any common themes or principles occurring in different situations might be identified and described.

In searching for possible explanations, it is necessary to determine the critical factors that contribute to this positive deviance, and in particular to try to identify which factors are predominantly behavioural, which are biological and environmental, which are innate, and which are acquired.

The major purpose in studying positive deviance is to learn from adaptive child-care and feeding behaviours, as well as from the social networks that support them, in order to design policies and develop programmes that reinforce and transfer these adaptive mechanisms to the malnourished. While other works have concentrated on socio-demographic and physiological variables associated with good growth, this stateof-the-art paper focuses on psychosocial and behavioural considerations.

The paper places positive deviance in an evolutionary context as a form of adaptation and reviews theories linking infant development to nutrition, from pre-natal life to breast-feeding, the introduction of solids, and the transition to an adult diet, following the infant up to two or three years of age. The book consists of two parts.

The first part documents the literature and its policy and programme implications. It defines positive deviance, presents an overview of what has already been written on the subject, gives overall conclusions, and makes policy recommendations. It seeks to link psychosocial and behavioural characteristics to child growth, and analyses the most proximate caretaker-child interaction, associated individual temperaments, and the social support systems in which such interaction is formed and nurtured. The section is designed to assist programme managers and policy-makers in the application of approaches that may be relevant to local socio-cultural and environmental conditions.

The second part examines considerations for research in positive deviance, underlining assumptions for research and relating that research to epidemiological methods. It presents a model for conducting programme-relevant research, a conceptual framework for this research, and an overview of important concepts and variables. It goes on to review a series of methodological problems and ways of dealing with them. Its purpose is to provide the type of methodological information needed to assist nutritionists and other social and biological scientists in developing research on positive deviance.

The emphasis placed on research considerations distinguishes this paper from other state-ofthe-art papers prepared for the WHO/UNICEF Joint Nutrition Support Programme (JNSP), which are much more application-oriented. The need to deal with research so extensively is predicated on the fact that the positive-deviance approach is relatively new to nutrition; as a result, little systematic research has hitherto been done in this area, and further study is needed in order to identify broadly applicable themes.