Presentation Matters: Effects of Cigarette Purchase Task Design on Systematic Data and Purchasing Behavior

Hypothetical purchase tasks (HPTs) are effective tools for evaluating participants' demand for substances. The present study evaluated the effect of task presentation on producing unsystematic data and purchasing behavior in a sample of individuals who smoke cigarettes. Participants (n = 365) were recruited from Amazon Mechanical Turk and randomly assigned to complete two of three HPT presentations: List (prices on one page in an increasing order), Ascending (one price per page in an increasing order), or Random (one price per page in a random order). We evaluated outcomes using a mixed model regression with a random effect for participants. We observed a significant effect of task presentation on passing the criterion assessing consistency in effects of contiguous prices (i.e., Bounce; X2(2) = 13.31, p = .001). A significant effect of task presentation on Trend or Reversals from Zero was not observed. For purchasing behavior, we observed a significant effect of task presentation on R2, X2(2) = 17.89, p < .001; BP1, X2(2) = 13.64, p = .001; ln(α), X2(2) = 332.94, p < .001; and ln(Omax), X2(2) = 20.26, p < .001; we did not observe a significant effect of task presentation on ln(Q0) or ln(Pmax). We recommend against using the Random HPT presentation to avoid unsystematic data. While the List and Ascending presentations do not differ across unsystematic criteria or purchasing behavior, the List presentation may be preferred due to participant experience. Public Health Significance The present study evaluated the presentation of hypothetical purchase tasks on unsystematic data and purchasing behavior. We report that purchase task presentation influences the rate of systematic data and certain indices of demand for cigarettes in a cigarette purchase task.