Development and results of a kidney disease knowledge survey given to patients with CKD

Background: Little is known about disease-specific knowledge in patients with chronic kidney disease (CKD). We developed and examined the results of a survey to characterize kidney disease knowledge.

Design: Survey about kidney disease knowledge, with questions developed by experts.

Setting & participants: 401 adult patients with CKD (stages 1-5) attending a nephrology clinic from April-October 2009.

Outcomes & measurements: We calculated survey reliability using the Kuder-Richardson-20 coefficient and established construct validity by testing a priori hypotheses of associations between survey results and patient characteristics. We descriptively analyzed survey responses and applied linear regression analyses to evaluate associations with patient characteristics. Health literacy was measured using the Rapid Estimate of Adult Literacy in Medicine.

Results: Participants' median age was 58 (25th-75th percentile, 46-68) years, 83% were white, 18% had limited literacy, and 77% had CKD stages 3-5. The 28-question knowledge survey had good reliability (Kuder-Richardson-20 coefficient = 0.72), and mean knowledge score was 66% ± 15% (SD). In support of the construct validity of our knowledge survey, bivariate analysis shows that scores were associated with age (β = -0.01/10 years; 95% CI, -0.02 to -0.005; P = 0.003), formal education (β = 0.09; 95% CI, 0.03-0.15; P = 0.004), health literacy (β = 0.06; 95% CI, 0.03-0.10; P = 0.001), kidney education class participation (β = 0.05; 95% CI, 0.01-0.09; P = 0.009), knowing someone else with CKD (β = 0.05; 95% CI, 0.02-0.08; P = 0.001), and awareness of one's own CKD diagnosis (β = 0.07; 95% CI, 0.04-0.10; P < 0.001). Findings were similar in adjusted analyses.

Limitations: Recruitment from 1 clinic limits generalizability of findings.

Conclusions: For patients with CKD, this Kidney Knowledge Survey (KiKS) is reliable and valid and identifies areas of and risk factors for poor kidney knowledge. Further study is needed to determine the impact of CKD knowledge on self-care behaviors and clinical outcomes.