A summary of the results of a series of studies of nonresponse and measurement error in the National Household Survey on Drug Abuse (NHSDA) is given in this chapter. Two studies not previously reported, the Skip Pattern Experiment and the Census Match Study, are the primary focus of the chapter. The Skip Pattern Experiment involved a test of a modified NHSDA questionnaire that made extensive use of skip patterns in drug use questions. Compared to the standard NHSDA method, which avoids skip patterns, the modified questionnaire tended to produce lower rates of reported drug use. The Census Match Study involved linking 1990 NHSDA nonrespondent cases with data from the 1990 Decennial Census. Household and individual data for NHSDA nonrespondents were obtained from the Census and used to characterize NHSDA nonresponse patterns in detail. A multilevel logistic model of response propensity identified the important predictors of nonresponse, including characteristics of the sampled person, the selected household, the neighborhood, and the interviewer.
