OBJECTIVES: The lack of specific validated PROs in RD is a strong limitation in patient centric clinical research. However, the development of disease-specific PROs for more than 7,000 RD is not a realistic objective. We worked at maximizing existing knowledge on RD and optimizing use of existing PROs to better capture the patient voice in RD clinical research.

METHODS: Orphanet conducted a systematic documentation of the functional consequences of 551 RD using the Orphanet Disability Questionnaire (ODQ), derived from the International Classification of Functioning (ICF). A Multiple Factorial Analysis (MFA) was performed to synthesize and analyze complex information generated by the 343 ODQ items, with the objective to regroup RD sharing similar functional impacts. To identify PROs matching RD functional impact profiles, Mapi Research Trust (MRT) applies the same ICF coding rule to a selection of PROs identified in MRT PROQOLID™ database and from a survey conducted among 24 European Reference Networks (ERN).

RESULTS: The MFA summarized 343 variables into 22 dimensions with more than 1% of explained variance, explaining 69.3% of total variance. The 551 RD were grouped into 57 clusters, of which 21 include 6 to 58 RD.

317 PROs developed in RD and 200 PROs measuring functional impacts were selected from PROQOLID™. The ERN survey identified 150 additional PROs. A preliminary coding at item level was conducted on a sample of 10 generic, disease-and function-specific PROs.

CONCLUSIONS: This project delivered a pilot clustering of 551 RD into 57 clusters, half of which were large enough to define informative functional impact profiles. We have tested ICF coding rules to PRO items, allowing ICF-coded RD clusters and relevant PROs to be matched. The next steps are to implement the coding rules to the full set of 467 PROs and to operationalize the identification of PROs through a repository platform.