In most depression studies, researchers rely on self-report questionnaires to measure symptoms. But members of our PPIE group told us these questionnaires can sometimes feel distressing, confusing, or too impersonal — and don’t always capture the changes in depression that matter most to them.

This raises important ethical and scientific questions:

• whether research participants are experiencing unnecessary distress?
• whether participants and researchers interpret the items in the same way?
• whether these questionnaires are sensitive to changes in the features of depression considered important by the patients we aim to help?

We don’t think anyone has looked at these issues in a systematic way.