Table 1.

Number of items, words, Flesch-Kincaid Grade and reading age of questionnaires

Instrument	No of items	Word count	Flesch-Kinkaid Grade	Reading age
Health Confidence Score	4	50	2.8	8
Health Literacy Questionnaire	44	1001	7.2	12
ICECAP-A	5	281	5.2	10
My Health Confidence	2	83	4.8	10
Patient Activation Measure (PAM-13)	13	299	8.2	13
Patient Health Engagement Scale	5	144	5.1	10
Stanford self-efficacy for managing chronic disease 6-item scale (Stanford 6)	6	212	8.5	14