Table 2. Study outcome and results.

Study	Prevalence of Low Health Literacy	Health Literacy Measure	Other Outcome Measures	Results
Bhat et al. (2008)[12]	REALM –89/447 (20%)	REALM	HAQ, and VAS for pain,fatigue, and stiffness.	Multivariate analysis found that levels of health literacy (low or adequate) did not have significant relationship with baseline or post-intervention health status i.e. disability (HAQ), pain, fatigue or stiffness.
Buchbinder et al. (2006) [13]	7/80 (9%) on TOFHLA and 8/80on REALM (10%).*	TOFHLA, REALM	Educational level	Significant numbers of patients with RA have low health literacy.
Hirsh et al. (2010) [15], Hirsh et al. (2011) [16]	35% inadequate or marginal(S-TOFHLA), 49% below highschool reading level (REALM),30% ‘somewhat confident’ orless (SILS).	2010: S-TOFHLA, REALM, SILS	Global assessment of disease state (based on MD-HAQ and DAS-28 scores), completed by patients and by health professionals.	Low health literacy independently associated with the extent of discrepancy between patient’s own assessment of health status as compared to physician’s assessment (p<0.001), with lower S-TOFHLA scores associated with wider gap between assessments (after adjustment for covariates). Limited health literacy REALM and TOFHLA) not associated with disease activity (DAS-28), including stiffness, pain, or steroid/biologic use.
Gordon et al. (2002) [14]	18/123 (15%) had REALMscores ≤60.	REALM	Interview and case record review for demographic data and clinic attendance. Functional status throughHAQ and HAD.	Low health literacy associated with anxiety (p = 0.011) and socioeconomic deprivation (p = 0.0064). Those with low literacy had more outpatient clinic visits than age and sex-matched literate (6 vs 2 visits/year) but HAQ score, sex, age, disease duration, joint replacement and number of previous disease modifying drugs not significantly different,
Kim et al. (2009)[17]	43 subjects (42%) had ascore<5, indicating lowhealth literacy	Korean version of TOFHLA	Questionnaire on educational level, and comorbidconditions	Individuals with low health literacy had significantly higher prevalence of arthritis than literate group (51% vs. 22%, p = 0.003). After adjusting for age and income, those with low health literacy had lower levels of physical function and subjective health, and more pain and limitations in activity.
Rudd et al.(2009) [19]	21% in the standard care and16% in intervention group werebelow high school levelreading	A-REALM (arthritis specific)	Adherence-scale, Lorig’s self-efficacy scale, Medical intervention satisfaction scale, appointment keeping, HAQ, mental health (subsection of SF-36)	Mental health significantly better (p = 0.04) in the intervention group at 6 months post intervention (but not significant at 12 months, p = 0.11); self-efficacy significantly better at 12 months (p = 0.04); other primary outcomes (adherence, satisfaction, appointment keeping) did not show any difference.
Quinlan et al. (2010) [18]	4/125 inadequate,5/125 marginal	Modified brief version of TOFHLA	Morisky Medication Adherence Scale, and adapted Arthritis Knowledge Questionnaire	In multivariate regression, level of health literacy was predictive of health knowledge (p = .002). However, level of health literacy was not a predictor of adherence (p  = .896) after controlling for health knowledge and patient covariates.
Swearingen et al. (2010) [20]	35/194 (18%) with REALM;24% with A-REALM	REALM, A-REALM (arthritis specific)	HAQ and MD-HAQ; physical function, pain, global status and laboratory tests	Univariate analysis: those with low health literacy had significantly poorer global status (p<0.05) and non-significantly poorer physical function, pain, fatigue, and inflammatory markers

Abbreviations: DAS 28 = 28 joint count disease activity score- measures swelling and tenderness in 28 joints; HAD = Hospital Anxiety and Depression questionnaire; HAQ = Health Assessment Questionnaire; health literacy = health literacy; MD-HAQ = multidimensional health assessment questionnaire; VAS = Visual Analogue Scale where an X on a line indicates a score between ‘very well’ and ‘very poorly’; RA = Rheumatoid Arthritis; SILS = single item literacy screener “how confident are you filling out medical forms by yourself?”.