Table 1 Outcome measures per measurement properties

Self-reported outcome measurement development

Concept elicitation: sample size (evaluated based on COSMIN guidelines) [20, 22]

Cognitive interview study: number of patients per item

Comprehensiveness: number of patients per item

Content validity

Relevance (patients): number of patients per item

Comprehensiveness (patient): number of patients per item

Comprehensibility (patient): number of patients per item

Relevance (professionals): number of professionals per item

Structural validity

Exploratory factor analysis (EFA)

Confirmatory factor analysis (CFA)

Internal consistency

Continuous scores: Cronbach’s alpha or omega

Dichotomous scores: Cronbach’s alpha or KR-20

Item response theory (IRT)-based scores: SE (θ) or reliability coefficient

Reliability

Continuous scores: intraclass correlation coefficient (ICC)

Dichotomous/nominal/ordinal scores: kappa, weighted kappa (ordinal scores)

Cross-cultural validity

Whether the PROM shows similar structural validity and reliability when validated in another cultural context or translated to another language