Table 3.

Correlation matrix of PREM^a items.^b

Variable	Patient experiences					Access to care
						Waiting times				Unmet medical needs
	Time	Understand	Questions	Decisions	Overall quality	oWT	oWP	aWT	aWP	Travel	Visit	Intervention	Medication
Timec	1.00
Understandd	0.75	1.00
Questionse	0.77	0.77	1.00
Decisionsf	0.71	0.76	0.83	1.00
Overall qualityg	–0.79	–0.75	–0.78	–0.74	1.00
oWTh	0.35	0.30	0.34	0.24	–0.36	1.00
oWPi	0.42	0.43	0.38	0.38	–0.45	0.67	1.00
aWTj	0.17	0.16	0.11	0.14	–0.12	0.11	0.15	1.00
aWPk	0.42	0.32	0.38	0.35	–0.37	0.32	0.50	0.67	1.00
Travell	0.20	0.21	0.21	0.24	–0.16	0.17	0.33	0.05	0.38	1.00
Visitm	0.36	0.30	0.36	0.27	–0.32	0.14	0.40	0.10	0.36	0.61	1.00
Interventionn	0.17	0.16	0.20	0.19	–0.18	0.12	0.37	0.18	0.44	0.61	0.89	1.00
Medicationo	0.22	0.23	0.26	0.16	–0.17	0.16	0.33	0.15	0.43	0.47	0.66	0.67	1.00
eHEALSp	–0.03	–0.13	–0.04	–0.04	0.11	0.01	0.14	–0.04	–0.02	–0.02	0.00	0.02	–0.06
Last visitq	0.03	-0.01	0.00	0.01	–0.06	0.00	0.06	–0.10	–0.08	0.00	–0.07	–0.10	–0.04

^aPREM: OECD (Organisation for Economic Co-operation and Development)-proposed set of questions on Patients’ Experiences with Ambulatory Care.

^bPairwise tetrachoric correlations for binary item pairs, polychoric correlations for polytomous items, polyserial and biserial correlations between eHEALS scores and polytomous and binary items, respectively.

^cDoctor spending enough time with patient in consultation (4-point Likert scale; higher points indicate more problems).

^dDoctor providing easy-to-understand explanations (4-point Likert scale; higher points indicate more problems).

^eDoctor giving opportunity to ask questions or raise concerns (4-point Likert scale; higher points indicate more problems).

^fDoctor involving patient in decisions about care and treatment (4-point Likert scale; higher points indicate more problems).

^gOverall quality of last appointment (5-point Likert scale; higher points indicate better experience).

^hWaiting time to be seen on the day of consultation (office waiting time [oWT]).

ⁱProblem with waiting to be seen on the day of consultation (office waiting was a problem [oWP]).

^jWaiting time to get the appointment (appointment waiting time [aWT]).

^kProblem with waiting for appointment: yes (appointment waiting time was a problem [aWP]).

^lMissed visit due to travel burden.

^mMissed visit due to cost burden.

ⁿMissed intervention due to cost burden.

^oMissed medication due to cost burden.

^peHEALS: eHealth Literacy Scale.

^qTime of last visit: 4 categories; higher points indicate more time elapsed since last visit.