|Chronic Energy Deficiency : Consequences and Related Issues (International Dietary Energy Consultative Group - IDECG, 1987, 201 pages)|
|Social and economic development: Report of working group 3*|
|2. Designs for studying the effects of low energy intake on behavior|
There are several alternative designs that can be utilized to assess the relationship of energy intake to behavior and to examine the socioeconomic consequences at the level of the individual, the household and the community. In a strict sense, it may be argued, as the anthropologist Edward Sapir suggested many years ago, that it is only the individual who thinks, feels, eats and acts - that behavior is a property of individuals.
However, we are concerned here not only with the consequences of chronically low energy intake for the individual, but also with the consequences for the organization and function of households and communities in which the individual members are subjected to low intake. Thus, the research design selected must permit assessment at three levels, which is to say that the study should have the community, the household, and the individual as units of analysis.
The behavioral impact of low intake can be examined in terms of 1 ) the effects of short-term deficits of energy intake relative to usual intake/expenditure patterns, or 2) the long-term effects of chronically low intake. Since energy deficits in relation to expenditure cannot be maintained over long periods of time, the focus on long-term consequences is essentially an assessment of the effects of achieving and maintaining energy balance at low levels of energy intake. The designs that follow can be used either for the purpose of assessing the behavioral and socioeconomic consequences of achieving energy balance at low levels or identifying short-term behavioral responses.
There are two general types of designs that are applicable: "observation studies" and "intervention studies". In the former type, the independent variable(s) represent some dimensions of the economic, social and cultural environment of the household and are measured as a phenomenon outside of investigator control. In contrast, "experimental studies" are characterized by a direct manipulation of the independent variable(s).