Age, depression, and attrition in the national survey of families and households

It might seem that following people over time provides the best indication of how people change with age, Sample attrition can undermine that assumption. This study describes the impact of health impairment, and depression on attrition in the Notional Survey of Families and Households. It analyzes the impact of that attrition on estimates of the age-specific changes in depression over a six-year period In doing so, it illustrates methods for assessing and perhaps correcting the effects of attrition. Results show that the cross-sectional relationship of baseline depression to age differs sharply for those who later drop out compared with those who stay in Much Of the difference, but not all, vanishes with adjustment for health and impairment. The probability of dropping out increases with poor health, impairment and depression at baseline. The impact of impairment and depression on attrition increases with age. Panel models that ignore the attrition imply that depression decreases in old age. Models that adjust for the hazard of attrition imply that depression riser by an amount that increases with age.