The population prevalence of problem gambling: methodological influences, standardized rates, jurisdictional differences, and worldwide trends
Av: Williams, R.J., Volberg, R.A. & Stevens, R.M.G.
The primary purpose of the present research was to standardize problem gambling prevalence rates so as to facilitate comparisons between jurisdictions as well as within the same jurisdiction over time. The first step in this process was the identification and collection of all published and unpublished studies that involve a jurisdiction-wide adult prevalence survey of problem gambling. A total of 202 studies were conducted between 1975 and 2012. All pertinent information was extracted from each of these 202 studies and is reported in Appendices A, B, C, and D. These Appendices represent the most complete collection of problem gambling prevalence studies to date and will serve as a database for future researchers. In addition, the demographic, characterological, environmental, and gambling format correlates of problem gambling in these 202 studies are summarized and reported in Appendices E, F, G, and H. The second step in this process was the examination of the impact of methodological differences on obtained problem gambling prevalence rates. The main methodological elements influencing obtained problem gambling prevalence are: a) which assessment instrument is used; b) the time frame used to assess the presence of problem gambling (i.e., past year, lifetime); c) how the survey is described to prospective participants; d) how the survey is administered (i.e., face-to-face, telephone, self-administered); and e) the threshold criterion that determines when problem gambling questions are asked. The methodological approach (within each of these elements) that produced the most valid prevalence rate was identified, as well as weighting factors that could be applied to obtain rates that would have been obtained using the more valid approach. The third part of this report presents the results of applying these weighting factors to create standardized past year problem gambling prevalence rates for all studies.