Development of the Rotterdam Renal Replacement Knowledge-Test (R3K-T)

Introduction: There is currently a lack of validated or standardized measures to test the level of knowledge among renal patients regarding kidney disease and available treatment options. We conducted a pilot study to develop a questionnaire measuring knowledge of kidney disease, dialysis and transplantation options. The main aim of this study was to develop such an instrument for further use in research and practice.
Method: An initial 61 item pool was generating by searching the literature and consulting experts in this area for additional items. This questionnaire was completed by 182 renal disease patients from 4 dialysis centers in the Rotterdam municipality. A factor analysis was conducted using the maximum likelihood factor method followed by direct oblimin rotation to obtain variance explained by each factor. Questions that loaded ≥ .30 on a factor were included.
Results: Twenty-seven patients (24%) were in the pre-RRT phase, 60 (54%) were undergoing haemodialysis, 16 (14%) were undergoing peritoneal dialysis, and 9 (8%) had a graft failure. Forty (36%) were female and 72 (64%) were male. Age range 19-87 (median = 59). A factor analysis was conducted to reduce the number of items. This resulted in 30 items consisting of 5 subscales regarding knowledge on: kidney disease (5 items, α = .37), peritoneal dialysis (4 items, α = .73), haemodialysis (4 items, α = .41), kidney transplantation (12 items, α = .86), quality of life (5 items, α = .59).
Discussion: This study aimed to develop an instrument with which knowledge of kidney disease and the related treatment options can be reliably measured. This study resulted in a short and easy to administer knowledge questionnaire. We intend to further explore the psychometric properties of this instrument and develop norm scores for the general public and patients at various stages of the disease and treatment. We have also considered translated versions of this questionnaire.