Person-Driven Mixed Methods Single Case Study Design - Rationale and Feasibility Study of a New Evaluative Service User Perspective Approach

The evaluation of psychiatric services from the perspective of service users faces considerable methodological challenges. Usually, the samples are small, there is a lack of control groups and recovery instruments are generally not reliable outcome measures. The person-driven mixed methods single case study design is an approach that attempts to deal with these methodological problems. Study participants are interviewed several times longitudinally using qualitative and quantitative interviews. The first interview acts as a control condition. In contrast to conventional mixed methods studies, the quantitative part is also defined from the perspective of the participating service users (PSYCHLOPS methodology). The paper explains the methodological background of the approach and reports on a feasibility study.