Economic Status Proxies in Studies of Fertility in Developing Countries: Does the Measure Matter?

Author(s): Bollen K A, Glanville J L, Stecklov G

Year: 2001

Abstract:
Practically every empirical study of fertility in developing countries includes economic variables as either a primary focus variable or as an important control variable. Yet economic status variables are included in various ways, and researchers have little guidance as to the implications of alternative approaches. This paper investigates the consequences of using different economic status proxies on the estimated impact of economic status and other determinants of fertility. Using micro survey data from Ghana and Peru and techniques for comparing non-nested models, we find that the proxies for income that best predict fertility are a principal components score of various consumer durable goods and an index that is constructed by summing ownership of those durable goods. The choice of the proxy used influences the predicted effects of some of the control variables, but overall the substantive conclusions are quite consistent. We also compare the results from using a restricted set of proxies such as those typically available in the Demographic and Health Surveys to the results obtained when we have a lengthier set of proxies. Though our focus is on childbearing, our results suggest implications beyond this specific dependent variable, providing researchers with an awareness of the sensitivity of microanalyses to the treatment of economic status. Our results also suggest practical recommendations for survey data collection.