There are a suite of self-report mental health questionnaires that started with the GHQ-60 which emerged in a mongraph in 1972. That was followed by shortened forms: the GHQ-30, GHQ-28 and GHQ-12. In many ways the GHQ-60, and then the shortened forms, led the explosion of modern short generic measures (in contrast to unifocal measures such as the BDI). Various of the GHQ forms have been used as therapy OMs since 1972 but they were designed more for research and community survey work and are not free. It appears that the copyright is currently held by GL-assesment, see https://www.gl-assessment.co.uk/assessments/products/general-health-questionnaire/. For more general information about the GHQ see https://eprovide.mapi-trust.org/instruments/general-health-questionnaire.