Differential attrition rates and active parental consent

Active parental consent in survey research poses ethical and practical conc erns. One common argument against the requirement of active consent procedu res is ifs effect on participation rates. There is additional concern that higher risk groups may be underrepresented in the final sample. Empirical s upport of differential attrition, however is lacking. In the current multis ite longitudinal study, passive consent procedures were approved for the co llection of protest data For subsequent years of data collection, active pa rental consent procedures were required. In this article we use the pretest data to examine demographic, attitudinal, and behavioral differences betwe en those students for whom active consent was provided and those for whom a ctive consent was either denied or for whom no response was received. The r esults indicate that active consent procedures produce deleterious effects on participation rates and lead to an underrepresentation of at-risk youth in the sample.