Case-mix adjustments for patient reported experience and outcome measures in primary care: an empirical approach to identify patient characteristics as case-mix adjusters based on a secondary analysis of an international survey among patients and their general practitioners in 34 countries

Journal of Patient-Reported Outcomes

Table 7 Overview of potential case-mix adjusters and whether or not adjustment is indicated

	Communi-cation	Access	Continuity	Comprehen-siveness	Self-reported health	Enable-ment
Age	Yes	Yes	Yes	Yes	Yes	Yes
Sex	No fixed effect	No fixed effect	Yes	No fixed effect	Yes	Yes
Education	No; slope effect important	Yes	Yes	Yes	Yes	Yes
Household income	Yes	Yes	No fixed effect	Yes	Yes	Yes
Ethnicity	No; slope effect important	Yes	Yes	Yes	Yes	Yes
Place of living	No; slope effect important	No; slope effect important	Yes	Yes	Yes	Yes
Self-rated health	Yes	Yes	No; slope effect important	Yes	-	Yes
Longstan-ding disease	Yes	No fixed effect	Yes	Yes	Yes	No fixed effect