Quantifying the negative impact of gambling: psychometric evaluation of the Spanish version of the Short Gambling Harm Scale (S-SGHS) among individuals engaged in gambling activities

Gambling-related harm (GRH) extends beyond addiction, affecting multiple life domains, yet validated tools for its assessment are currently lacking for the Spanish population. This study adapted and validated a Spanish version of the Gambling-Related Harm Checklist (GRH-CL) and developed a short form (S-SGHS) to quantify GRH and facilitate population-level metrics. A Spanish survey of 800 individuals, with gambling experience in the past year, assessed their gambling behaviors, GRH (via the 72-item GRH-CL), the Problem Gambling Severity Index (PGSI), and quality of life (SF-6D, TECVASP). Confirmatory Factor Analysis (CFA) supported a unidimensional structure for the 72-item. Using a genetic algorithm and manual Item Response Theory (IRT) selection, a 12-item short form (S-SGHS) was derived, showing strong internal consistency and gender invariance. The S-SGHS demonstrated good predictive validity over the PGSI for quality of life (SF-6D, TECVASP), highlighting its sensitivity to subtle harms. Results underscore the need for culturally tailored instruments. The S-SGHS enables nuanced public health evaluations, informing preventive strategies beyond clinical addiction frameworks. This study provides the first validated Spanish tool for GRH assessment, advancing insights into gambling’s multifaceted impacts.