Validation of the gambling harm measure across three independent samples

Gambling-related harm (GRH) has become an increasingly popular topic in gambling research. However, several issues concern existing measures of gambling-related harm. The objective of this study was to validate a new measure of GRH, the Gambling Harm Measure (GHM). The GHM is a 16-item instrument that assesses varying levels of harm across six different life domains: financial, psychological, relationship, physical, work/study, and legal. A secondary analysis of data from three independent samples (n = 9,913) was conducted to determine the GHM's factor structure and its association with alternative measures of gambling-related harm and gambling intensity. Confirmatory factor analyses provided the strongest support for a unidimensional factor structure, indicating that the GHM is best scored as the sum of items endorsed. This factor structure was invariant to differences between samples, age groups, and sexes. Correlational analyses revealed stronger associations between total score on the GHM and alternative measures of GRH compared to measures of other substance-related and behavioral addictions. Finally, generalized linear mixed modeling demonstrated a positive effect of gambling intensity on GHM scores. This study provides support for the use of the GHM as a valid, unidimensional measure of gambling-related harm.