Table 4a.

Content validity assessment of the SAPSS.

	PROM development study 1	PROM development study 2	Content validity study	Rating of reviewers	Overall rating per PROM	Quality of evidence
Self-administered patient satisfaction scale	Development study [67]	Development study [20]	NA	+/−/?	+/−/±	High, moderate, low, very low
Relevance
1. Are the items relevant to the construct of interest?	–	–		+
2. Are the included items relevant for the target population of interest?	–	–		+
3. Are the included items relevant for the context of interest?	+	+		+
4. Are the response options appropriate?	–	–		+
5. Is the recall period appropriate?	–	–		?
Relevance rating	–	–	NA	+	±	Low
Comprehensiveness
6. Are all key concepts included?	–	–		–
Comprehensiveness rating	–	–	NA	–	–	Low
Comprehensibility
7. Are the PROM instructions understood by the population of interest as intended?	–	–
8. Are the PROM items and response options understood by the population of interest as intended?	–	–
9. Are the PROM items appropriately worded?				+
10. Do the response options match the question?				+
Comprehensibility rating		–	NA	+	±	Low
Content validity rating					–	Low

Legend: - Fail + Pass ? Insufficient information ± Inconsistent.