Design and Methods of the New Zealand National Gambling Study, a Prospective Cohort Study of Gambling and Health: 2012–2019

By Abbott, M., Bellringer, M., Garrett, N., & Kolandai-Matchett, K.

Abstract: This paper describes the design, sampling, recruitment, and data analysis of the prospective, nationally representative New Zealand National Gambling Study. Particular aspects of the study were critical for its success as a longitudinal epidemiologic study, making its methodology beneficial for replication in other jurisdictions. At baseline (2012), 6251 adults were interviewed and followed-up in 2013, 2014, and 2015. An additional cohort of 106 moderate-risk/problem gamblers interviewed at baseline (2014–2015) and follow-up (2015–2016) increased the number of these groups in the study. Measures included gambling commencement, gambling frequency, gambling risk levels, at-risk and problem gambling development (incidence), comorbidity, problem gambling cessation, and relapse. Future stages include a follow-up assessment in 2019 and a qualitative study. The study design enables assessment of population and individual level changes and transitions over time, identification of risk and protective factors, and comparisons with previous similarly designed prospective studies. Methods for enhancing response rates and retention are discussed.

Abbott, M., Bellringer, M., Garrett, N., & Kolandai-Matchett, K. (2017). Design and Methods of the New Zealand National Gambling Study, a Prospective Cohort Study of Gambling and Health: 2012–2019. International Journal of Mental Health and Addiction, 15(6), 1242–1269.



The Longitudinal Relationships Between Psychiatric Disorders and Gambling Disorders

Hartmann, M. & Blaszczynski, A.

The literature has consistently reported an association between gambling disorders and various comorbid psychiatric and substance conditions. The majority of studies have been cross-sectional in nature, and therefore fail to describe the temporal sequences between these conditions. To investigate these temporal sequences we conducted a scoping review of empirical longitudinal studies that have explored the relationships between gambling disorders and comorbid psychiatric disorders, including any mood and anxiety disorders, suicidal ideations and attempts, and illicit substance, nicotine and alcohol use and dependence. A search was conducted for peer reviewed and unpublished articles, and government reports published between January 2000 and March 2015, with a main focus on the temporal sequence between these two conditions. Studies were only included if they were in English, prospective in nature, studied treatment and population samples and included any form of gambling. A total of 35 publications were identified and the findings discussed in terms of three populations: (i) specific populations, (ii) children, adolescents, and young adults, and (iii) adults. On the basis of these longitudinal findings it is suggested that psychiatric disorders can represent both a precursor and a consequence of problem gambling, and that there are underlying interactive factors, such as impulsivity that can predict and drive both temporal sequences. Screening for comorbid psychiatric conditions upon entering treatment for problem gambling should form an integral part of clinical assessments. However, the extent to which comorbid conditions contribute causally to the development of gambling disorders remains to be conclusively established.

Hartmann, M. & Blaszczynski, A. Int J Ment Health Addiction (2016). doi:10.1007/s11469-016-9705-z

Changes in risky gambling prevalence among a New Zealand population cohort

Evidence suggests that problem gambling is an unstable state where gamblers move into and out of risk over time. This article looks at longitudinal changes in risky gambling and the factors associated with an increased risk (measured by the Problem Gambling Severity Index [PGSI]) in the current New Zealand context, which has experienced a doubling of the electronic gaming machine (EGM) market over the last two decades. Respondents from a nationally representative baseline sample (n = 2672) were recontacted two years later to assess changes in gambling behaviours. Among the 901 respondents reached at follow-up, average gambling risk increased over time, and the prevalence of those who had at least some level of gambling risk (i.e. low-risk or greater) more than doubled (from 4.7% to 12.4%). The majority (80.2%) of those who were at risk at follow-up had not been at risk at baseline. Multivariate linear regression analyses show that the predictors of low to moderate increased risk include Pacific ethnicity; high neighbourhood deprivation status; baseline frequent, continuous gambler type; baseline PGSI status; and playing EGMs. These findings highlight the need to develop theories of gambling addiction trajectories and to identify the earliest point along the trajectory where public health interventions should occur.

Kruse, K., White, J., Walton, D. K., & Tu, D. (2016). Changes in risky gambling prevalence among a New Zealand population cohort. International Gambling Studies, 0(0), 1–19.