Table 1.

Characteristics of studies included in the review

Study/Reference/Year/Location/NMedian Age, yr [Mean]Men, %CKD StageAimDesignSetting and Recruitment MethodParticipantsExclusion CriteriaHealth Literacy MeasureOutcome Variables TestedPrevalence of Limited Health Literacy, %
Adeseun (34)[52]68Incident dialysis (HD or PD)Examine relationship between health literacy and CV disease risk factorsCohort (baseline data)Adults from transplant evaluation clinics taking part in the Dialysis Heart and Bone Study100% with limited health literacy were black compared with 50% of those with adequate health literacyPrevious coronary revascularization, cardiac devices, or weight >350 lbSTOFHLABP, lipid profile, waist-to-hip ratio, BMI, tobacco use21
2012
US
72
Boulware (35)6040Nondialysis CKD 3–5Compare the effectiveness of educational interventions on preemptive living donor kidney transplantationCohort (baseline data)Nephrology clinics46% White, 47% black,<1% Hispanic<18 or >70 yr old, non-English speaking, previous transplant, cancer, heart failure, severe liver disease, PVD, HIV, unstable coronary artery diseaseREALM25
2013
US
130
Brice (24)Prevalent HDValidate TILS and SILS against STOFHLACross-sectionalAdults from seven HD centersEnglish (96%) and Spanish speakers (4%)<18 yr old, unable to speak English or Spanish, mental impairment defined by dialysis staff, poor visionSTOFHLA, SILS and TILS (English or Spanish)45 (STOFHLA),22 (SILS)
2014
US
277
Cavanaugh 1 (21)a6256Incident HDMeasure the prevalence and associations of limited health literacy and risk of all-cause mortalityCohortAdults “eligible for a patient education program” from 77 dialysis units, health literacy measured if low literacy was suspected by case manager52% White, 50% diabetic<18 yr old, patients on nonpermanent dialysis, known cognitive impairment, non-English speakers, nursing home residentsREALMMortality32
2010
US
480
Cavanaugh 2 (23)[52]51Prevalent HDValidate BHLS against REALM and STOFHLACross-sectionalAdults from four dialysis units73% Black<18 or >80 yr old, dialysis initiation <1 mo, non-English speakers, cognitive impairmentBHLS (0–15), REALM, and STOFHLA23 (BHLS) 27 (REALM) 8 (STOFHLA)
2015
US
143
Dageforde 1 (36)[48]64Incident transplantCompare health literacy between live and deceased donor kidney transplant recipients and live kidney donorsRetrospective chart reviewTransplant recipients and donors at single transplant center surveyed for health literacy preoperatively65% White LDR (n=103) DDR (n=152)<18 yr old, no recorded answer to BHLSBHLS (0–15)Donor type, education, and demographics12 (LDRs: 9%; DDRs: 14%)
2014
US
255
Dageforde 2 (37)[53]61Dialysis (n=14) and nondialysis CKD (n=90)Characteristics of attenders versus absentees for kidney transplant evaluation appointmentsCross-sectionalConvenience sample of patients scheduled for initial evaluation for kidney transplant at a single center46% White<18 yr old, non-English speakers, cognitive impairmentBHLS (0–15)Attendance versus nonattendance23 (14% dialysis; 24% CKD)
2015
US
104
Devraj (38)45% over 60 yr old47Nondialysis CKD 1–4Relationship between health literacy and eGFRCross-sectionalAdults attending follow-up nephrology outpatient appointments at a single center, given a $20 merchandise card to participate40% White, 41% Hispanic<21 yr old, non-English speaking, AKI, cognitive impairment defined by medical notes or if less than four on cognition screening test, poor visual acuityNVSeGFR (MDRD formula)63
2015
US
150
Foster (39)[58]54Prevalent dialysis (HD or PD)Assess disaster preparedness in patients on dialysisCross-sectionalAdults approached during dialysis at six dialysis units57% Black, 6% Spanish speaking, 94% English speaking<18 yr old, unable to understand consent processSTOFHLA (English or Spanish)Disaster preparedness49.5
2011
US
238
Gordon (18)a[47]57TransplantRelationship between health literacy, transplant knowledge, and graft functionCross-sectionalSequential transplant recipients from a single center recruited at post-transplant clinic visit for 30-min interview<18 yr old, non-English-speaking, visually impaired, too unwell to participateSTOFHLA and REALM-TDemographics and graft function9
2011
US
124
Green (19)a6457Prevalent HDDescribe prevalence and associations of limited health literacyCohort (baseline data)Patients from nine dialysis units included in an RCT of strategies for managing pain, sexual dysfunction, and depression40% Black<18 yr old, less than thrice-weekly dialysis, non-English speakers, cognitive impairment, considering switch to PD or transplantationREALMDemographics, SES, comorbidity16
2011
US
260
Grubbs (20)a[52]66Prevalent HDAssociation of poor health literacy with access to transplantationCross-sectionalAdults approached during dialysis session in five dialysis units73% Black<18 or >75 yr old, ethnicity other than black or white, <9 mo on dialysis, previous transplant, cognitive impairmentSTOFHLAReferral for transplant evaluation, wait listing, or transplantation32
2009
US
62
McNaughton (40)5557CKD 3–5, including dialysis or transplant if eGFR<60 ml/min per 1.73 m2Relationship between limited health literacy and BP at ED presentationCross-sectionalAdults attending ED at a large quaternary hospital screened for health literacy as part of admission nursing assessmentStudy included 31,902 patients, of whom 851 (3%) had kidney disease, 60% white<18 yr old, nursing assessment or health literacy measure not completed, admitted with preeclampsia or alcohol withdrawalBHLS (0–15)BP at hospital presentation (in all ED attenders)26b
2014
US
851b
Miller-Matero (41)Referred for transplantation (dialysis or advanced CKD)Assess health literacy of patients referred for solid organ transplantationCross-sectionalPatients considered for solid organ transplantation at a single centerREALMDemographics, cognitive impairment, reading ability, numeracy (in all organ transplant recipients)37.8
2015
US
95
Ricardo (42)[58]54Nondialysis CKD 1–4Association of limited health literacy with kidney function and CV risk factorsCross-sectionalAdults with CKD recruited from seven clinical centers52% White, 48% black<21 or >74 yr old, polycystic kidney disease (43), Hispanic ethnicitySTOFHLAeGFR (MDRD formula), BP, LDL cholesterol <100 mg/dl, HbA1c<7%, self-reported CV disease16 (Black, 28%; white, 5%)
2014
US
2340
Robinson (43)[50]59Prevalent transplantValidate a sun-protection education programRCT (baseline data)Adults from two transplant programs35% Black, 28% Hispanic, 36% white<2 or >24 mo after transplant, non-Spanish speakers, <18 or >70 yr old, poor vision, ethnicity other than black, white, or HispanicSTOFHLA (English or Spanish)36 (Black, 58%; Hispanic, 54%;white, 0%)
2015
US
170
Taylor (44)5462Incident dialysis (HD or PD), incident transplant and transplant waitlisted (prevalent dialysis and nondialysis CKD)Describe prevalence and associations of limited health literacyCohort (baseline data)Adults approached for notes review and survey from all 71 United Kingdom renal unitsRepresentative nationwide sample, 79% white, patients with CKD not on dialysis were all preemptively waitlisted for transplant<18 or >75 yr old or unable to provide informed consentSILSDemographics, SES, comorbidity16 (Dialysis, 18%; CKD wait listed, 9%; incident transplant, 12%)
2015
UK
5520
Weng (45)[55]60Prevalent transplantPrevalence and correlates of medication nonadherenceCross-sectionalAdults approached during a transplant clinic visit at a single center, offered $1558% White, 27% black, median 2.9 yr post-transplant<6 mo Post-transplant, <18 yr old, non-English speakers, unable to consent, dual organ transplantSTOFHLAMedication nonadherence2.4
2013
US
252
Wright (47)a5853Nondialysis CKD 1–5Measure awareness and knowledge of CKD to develop a CKD knowledge surveyCross-sectionalAdults attending a follow-up nephrology clinic appointment at a single center, offered $1083% White<18 yr old, non-English speakers, kidney transplant or dialysis, vision or cognitive impairmentREALMKidney disease knowledge18
2011
US
401
Wright-Nunes (46)5854Nondialysis CKD 1–5Assess feasibility and effect of a physician-delivered education tool to increase CKD knowledgeClinical trial, (baseline data)Adults at single center asked to complete a survey (written or read aloud), offered monetary compensation77% White, 78% CKD 3–5<18 yr old, non-English speakers, kidney transplant or dialysis, vision or cognitive impairmentREALM22
2013
US
154c
  • Outcome variables are listed only if statistical models included health literacy as an exposure variable. US, United States; HD, hemodialysis; PD, peritoneal dialysis; CV, cardiovascular; STOFHLA, Short Test of Functional Health Literacy in Adults; BMI, body mass index; PVD, peripheral vascular disease; REALM, Rapid Evaluation of Adult Literacy in Medicine; —, data unavailable or no outcomes tested; TILS, Two-Item Literacy Screener; SILS, Single-Item Literacy Screener; BHLS, Brief Health Literacy Screener; LDR, live donor recipient; DDR, deceased donor recipient; NVS, Newest Vital Sign; MDRD, Modification of Diet in Renal Disease; REALM-T, transplant-specific version of the Rapid Estimate of Adult Literacy in Medicine; RCT, randomized controlled trial; ED, emergency department; HbA1c, hemoglobin A1c;UK, United Kingdom; SES, socioeconomic status.

  • a Studies included in the 2012 review by Fraser et al. (17).

  • b Frequencies from personal communication with the authors (C. McNaughton).

  • c After excluding 401 from ref. 48.