What Matters Most? Developing a Core Patient Reported Outcome Set for Individuals With Genetic Intellectual Disabilities: An International Delphi Study

BACKGROUND: Improving care and research for individuals with genetic intellectual disabilities (GID) requires the identification and measurement of relevant patient reported outcomes (PROs). PROs represent the patient perspective on their health status. Currently, a myriad of potentially irrelevant PROs is being measured for individuals with GID. Therefore, the aim of this study is to identify the most relevant PROs through a Delphi survey and consensus meetings and develop a generic core PRO set applicable to the whole GID population to be used in care and research. METHODS: PROs, previously identified through a comprehensive literature review and a qualitative study, were integrated and conceptualised into a pilot generic core PRO set with an expert group. This pilot set was presented in a two-round Delphi survey with individuals with GID, caregivers and experts. Consensus was set at 60% or more of all participant groups rating a PRO as important for inclusion in the final core PRO set, or as not important for exclusion. The Delphi surveys were followed by two consensus meetings with individuals with GID, caregivers and experts to reach consensus on the undecided PROs. RESULTS: Twelve individuals with GID, 21 caregivers and 28 experts (total n = 61) participated in the first Delphi round. Twenty-nine PROs were presented to the participants. In the first round, consensus was reached on one important PRO 'fatigue'. In the second round, consensus was reached on 12 important PROs: fatigue, sleep, physical functioning/activities, quality of life, social functioning/participation, perceived health, cognitive functioning, depressive symptoms, mobility/functioning of the lower extremities, receptive communication, expressive communication and sensory overresponsivity. During the consensus meetings, consensus was reached on seven additional important PROs: pain, anxiety/stress, anger, vision, hearing, gastrointestinal symptoms and mental functioning. This resulted in a final generic core PRO set including the 19 PROs. CONCLUSIONS: This study identified the most relevant PROs for GID, marking the final step in developing a generic core PRO set for the whole GID population. This GID core PRO set provides a framework to guide care, research and policymaking. The next step involves selecting and validating corresponding patient reported outcome measures (PROMs) to adequately measure these PROs: the GID core PROM set.