Identifying the core and peripheral criteria for gambling and gaming disorders within the World Health Organization diagnostic framework in a nationally representative sample.

Gambling disorder and gaming disorder are increasingly recognized as significant contributors to affective disorders, highlighting the need to better understand their diagnostic frameworks. The aim of this study was to compare "core" and "peripheral" diagnostic criteria for gaming disorder and evaluate these distinctions within gambling disorder for the first time. A nationally representative sample of 1074 British adults completed online assessments of gambling and gaming disorders per the World Health Organization's (WHO) eleventh revision of the International Classification of Diseases (ICD-11). Condition Inferential Tree analyses identified which criteria best predicted high-risk behavior. Prevalence was low for gambling disorder (0.49 %) and gaming disorder (0.30 %), though high-risk cases were more frequent (2.47 % and 2.27 %, respectively). In gambling disorder, the experience of significant distress/impairment (criterion 4), increased priority (criterion 2), and continuation/escalation (criterion 3) emerged as core criteria while impaired control (criterion 1) was peripheral. For gaming disorder, the experience of significant distress/impairment (criterion 4), continuation/escalation (criterion 3), and impaired control (criterion 1) were core and increased priority (criterion 2) peripheral. It is feasible to distinguish core from peripheral criteria in both disorders, but doing so requires a careful, severity-sensitive approach. The findings imply that distinguishing core from peripheral diagnostic criteria in gambling and gaming disorders provides a useful severity-sensitive framework that clarifies their links with affective disorders. Specifically, this distinction helps clinicians target the symptoms most likely to worsen mood dysregulation and guides research into shared mechanisms, improving prevention and treatment for comorbid affective and behavioral disorders.