In this overview of the measurement of prevalence of youth problem gambling literature commissioned by the Department of Family and Community Services, the researchers have confined the task to a review of instruments for measuring problem gambling prevalence, the application and results of selected prevalence studies and a discussion of methodological considerations. The researchers were invited to present their conclusions or recommendations for the future.
Specifically, in relation to existing prevalence studies on youth problem gambling we able to conclude:
- there is ‘no gold standard’, no single instrument that is better than another; and while the desire of researchers is to establish one internationally accepted gold standard measure, few advances have been made in this regard;
- the use of different instruments and differences in criteria and thresholds leads to quite different prevalence rates even when administered to the same sample. The threshold or cut off can be applied conservatively or liberally, so that ‘no prevalence estimate exists independent of the criteria used to determine the disorder’ (Shaffer). This statement is confirmed in our review of prevalence studies;
- prevalence rates are partially a product of the screening tools used;
- the Productivity Commission noted that ‘it is difficult to measure problem gambling among populations, and no existing single test instrument is perfect. The Commission used SOGS, self assessment methods and other methods to assess harm and prevalence rates, arguing that ‘ a three way approach is better than relying on a single measure.’ (6.1);
- based on the review of available screens, if a major national prevalence study were to be undertaken then consideration should be given to the use of DSM-IVMR- J for adolescents as it has a low reading age that should facilitate accurate responses. It would also be advisable to include a second screening instrument in a self-assessment, paper and pencil exercise and we advise that the SOGS-RA should be included. We advise using two screens with several groups. While there is no gold standard the choice of SOGS-RA and DSM-IV-MR-J are likely to facilitate better international comparisons;
- a longitudinal study where gambling issues are integrated into broader health issues may in fact, be the preferred approach. It is clear that gambling preferences (and opportunities) change with age while high youth prevalence rates do not appear to translate into equally high rates for adults. Documenting changes in preferences would be part of any longitudinal study. Other issues would include: does gambling frequency peak and then decline; need to separate wagering from gambling, ability to test hypotheses in longitudinal study. Time interval is important for measuring rate or prevalence.
A longitudinal study would represent a more comprehensive approach to understanding youth gambling behaviours. It could be incorporated in a much broader study including for example with leisure, health and well-being or substance use surveys. The design of such a study would need to consider the following:
- sample of Year 8-12 secondary students;
- followed up at two year intervals;
- follow up at least three times to ensure that the age range was approximately 13- 24 over the life of the study;
- use of two screening instruments included in the survey;
- obtain three snapshots or point in time estimates by applying the two screens at three different intervals;
- survey design capable of obtaining information on changing preferences with age;
- longitudinal study has the potential to capture the impact of changing technologies and up take of new technology for gambling or wagering;
- potential benefit if New Zealand would also be involved to provide international comparison; and
- how to incorporate self-awareness feedback in the design of such a study.