California Center for Population Research

Data from three waves of the Indonesia Family Life Survey (IFLS) are used to examine follow-up and attrition in the context of a large scale panel survey conducted in a low income setting. Household-level attrition between the baseline and first follow-up four years later is 6%; the cumulative attrition between the baseline and second follow-up after a five year hiatus is 5%. Attrition is low in the IFLS because movers are followed: around 12% of households that were interviewed had moved from their location at baseline. About half of those households were "local movers." The other half, many of whom had moved to a new province, were interviewed during a second sweep through the study areas ("2 nd tracking"). Regression analyses indicate that in terms of household-level characteristics at baseline, households interviewed during 2 nd tracking are very similar to those not interviewed in the follow-up surveys. Local movers are more similar to the households found in the baseline location in the follow-ups. The results suggest that the information content of households interviewed during 2 nd tracking is probably high. The costs of following those respondents is relatively modest in the IFLS. While the analytical value of re-interviewing movers will vary depending on the specifics of the research, we conclude that, in general, tracking movers is a worthwhile investment in longitudinal household surveys conducted in settings where communication infrastructure is limited.