Is more health always better? Exploring public preferences that violate monotonicity

Abásolo and Tsuchiya (2004a) report on an empirical study to elicit public preferences regarding the efficiency-equality trade-off in health, where the majority of respondents violated monotonicity. The procedure used has been subject to criticisms regarding potential biases in the results. The aim of this paper is to analyse whether violation of monotonicity remains when a revised questionnaire is used. We test: whether monotonicity is violated when we allow for inequality neutral preferences and also if we allow for preferences that would reject any option which gives no health gain to one group; whether those who violate monotonicity actually have non-monotonic or Rawlsian preferences; whether the titration sequence of the original questionnaire may have biased the results; whether monotonicity is violated when an alternative question is administered. Finally, we also test for symmetry of preferences. The results confirm the evidence of the previous study regarding violation of monotonicity.