Table 2.

Summary of criteria to evaluate applicability of vision impairment PROMs based on FDA guidelines

Criteria	Definition
Validity	The capacity of the PROM to describe the trait it intends to measure  e.g., content-related, criterion-related, predictive
Reliability	The consistency of the measurements taken by the PROM  “How the person functions” in regards to their vision e.g., test–retest, internal consistency, inter-interviewer reproducibility
Sensitivity	The instruments’ ability to detect a change in the population  e.g., effect size, standard error
Representative populationa	A PROM should be developed with the target population for the target population  In the case of IRD, there are many subtypes and so a representative sample for PROM development consisting of IRD’s three electroretinogram subtypes (rod-cone dystrophy, cone/cone-rod dystrophy, and macular dystrophy)

PROM patient-reported outcome measure

^aAdditional criteria set out by the US Food and Drug Administration (FDA)