ABSTRACTBackground: There are many validated and widely used assessments within aphasiology. Few, however, describe language and life with aphasia from the perspective of the person with aphasia. Across healthcare, patient experience and user involvement are increasingly acknowledged as fundamental to person-centred care. As part of this movement, Patient Reported Outcome Measures (PROMs) are being used in service evaluation and planning.Aims: This paper reports the quantitative aspects of a mixed methods study that developed and validated a concise PROM, the Aphasia Impact Questionnaire (AIQ), co-produced with People with Aphasia (PWA).Methods & Procedures: The AIQ was developed within the social model of disability and all stages of the development of the AIQ were performed in partnership with PWA. It was adapted from a pre-existing and lengthier PROM for PWA, the Communication Disability Profile. The first iterations of the AIQ focused on domains of communication, participation and well-being/emotional state. Subsequently the AIQ was extended to include additional items relating to reading and writing (AIQ-21). The research design was iterative. Initially, concurrent validity, internal consistency, and sensitivity of the AIQ-prototype were obtained. The AIQ-prototype was modified to become the AIQ-21. Statistical testing with a new group of PWA was performed, investigating internal consistency and concurrent validity of the AIQ-21.Outcomes & Results: Results for both the AIQ-prototype and AIQ-21 showed statistically significant concurrent validity and good internal consistency. Repeated measurement using the AIQ-prototype demonstrated statistically significant change after PWA accessed a community intervention.Conclusions: The AIQ-21 is a PROM that has great potential to be one of the core set of aphasia tests for clinical and research use. Results can be used alongside language assessment to enable person-centred goal setting and partnership working for people with aphasia.