Background: To provide a model for Public involvement (PI) in instrument development and other research based on lessons learnt in the co-production of a recently developed mental health patient reported outcome measure called Recovering Quality of Life (ReQoL). While service users contributed to the project as research participants, this paper focuses on the role of expert service users as research partners, hence referred to as expert service users or PI. Methods: At every stage of the development, service users influenced the design, content and face validity of the measure, collaborating with other researchers, clinicians and stakeholders who were central to this research. Expert service users were integral to the Scientific Group which was the main decision-making body, and also provided advice through the Expert Service User Group. Results: During the theme and item generation phase (stage 1) expert service users affirmed the appropriateness of the seven domains of the Patient Reported Outcome Measure (activity, hope, belonging and relationships, self-perception, wellbeing, autonomy, and physical health). Expert service users added an extra 58 items to the pool of 180 items and commented on the results from the face and content validity testing (stage 2) of a refined pool of 88. In the item reduction and scale generation phase (stage 3), expert service users contributed to discussions concerning the ordering and clustering of the themes and items and finalised the measures. Expert service users were also involved in the implementation and dissemination of ReQoL (stage 4). Expert service users contributed to the interpretation of findings, provided inputs at every stage of the project and were key decision-makers. The challenges include additional work to make the technical materials accessible, extra time to the project timescales, including time to achieve consensus from different opinions, sometimes strongly held, and extra costs. Conclusion: This study demonstrates a successful example of how PI can be embedded in research, namely in instrument development. The rewards of doing so cannot be emphasised enough but there are challenges, albeit surmountable ones. Researchers should anticipate and address those challenges during the planning stage of the project.
- Mental health
- Outcome measure
- Patient and public involvement (PPI)
- Patient reported outcome measure (PROM)
- Public involvement
- Service user