Agreement Between Retrospective Accounts of Substance Use and Earlier Reported Substance Use

This present study examined agreement between retrospective accounts of substance use and earlier re ported substance use in a high school age sample. Three issues were addressed: (1) extent of overall agreement; (2) evidence for the presence of a response-shift bias; and (3) extent to which current use biases recall of substance use. Subjects were 415 high school students who took part in a smoking prevention program. At the last measurement, which took place 2½ years after the pretest, the students were asked to recall pretest use of tobacco, alcohol, and marijuana, and use one year earlier. Results showed an overall tendency for students to recall less use of uncontrolled substances than had been previously reported. For the one controlled substance included in the questionnaire, marijuana, current nonusers tended to recall less use than they had reported at the time, whereas current users tended to recall more use than had been re ported. The present study found no evidence for a response-shift bias. It is suggested that the explicitly worded anchors on the response scales helped prevent such a bias. Finally, the results suggest that current use biases recall of past use to a substantial extent, and that this bias affects recall of alcohol use most se verely.