Abstract
We experimentally evaluate inexpensive interventions to increase response fractions in two alcohol surveys. Residents on the New Zealand General and Maori electoral rolls were randomized to receive a survey pack with or without an offer of entry to a $500 prize draw. Subsequent randomization of sample members who did not initially respond allowed estimation of effects of offering a $5 donation to charity as an incentive to respond. Offering prize draw entry did not significantly increase responses in either population. Contrary to expectation, promising a $5 donation to non-respondents reduced subsequent responding in the group previously offered the prize draw incentive.