> The problem is most of these things are not easily and correctly measured by a questionnaire. You need more expertise to get this information out of a patient

> The problem is most of these things are not easily and correctly measured by a questionnaire. You need more expertise to get this information out of a patient. It sounds like you're agreeing. Mental health is subjective feelings. When we want to study it, we reduce it to an objective measure of a few dimensions, like those diagnostic questionnaires. This removes its complexities, but also allows some level of standardisation across studies.