Methodological problems in research on treatments for pathological gambling.

These common methodological problems affect the usefulness of pathological gambling (PG) treatment research: (1) Most PG etiological models derive from substance abuse; (2) Most PGs recover on their own and few seek treatment, so PGs in treatment studies may not be representative; (3) Data on treatment-seeking PG women, older adults, and minority group members, or on group, marital, and psychodynamic approaches to PG, are sparse; (4) Little research has examined the impact of comorbidity on PG treatment response; (5) Design deficiencies burden many PG treatment studies.