The ordering of gambling severity and harm scales: A cautionary tale

Question-order effects are known to occur in surveys, particularly those that measure subjective experiences. The presence of context effects will impact the comparability of results if questions have not been presented in a consistent manner. In this study, we examined the influence of question order on how people responded to two gambling scales in the Australian Capital Territory Gambling Prevalence Survey: The Problem Gambling Severity Index and the Short Gambling Harm Screen. The application of these scales in gambling surveys is continuing to grow, the results being compared across time and between jurisdictions, countries, and populations. Here we outline a survey experiment that randomized the question ordering of these two scales. The results show that question-order effects are present for these scales, demonstrating that results from them may not be comparable across jurisdictions if the scales have not been presented consistently across surveys. These findings highlight the importance of testing for the presence of question-order effects, particularly for those scales that measure subjective experiences, and correcting for such effects where they exist by randomizing scale order.