Description

The Kidney Disease Quality of Life-36 (KDQOL-36) is a standardized, disease-specific health-related quality of life (HRQoL) instrument developed to assess the physical, psychological, social, and disease-specific impact of chronic kidney disease (CKD) on patients’ daily lives. It is one of the most widely used and internationally validated patient-reported outcome measures (PROMs) for individuals with chronic kidney disease, including those receiving hemodialysis, peritoneal dialysis, conservative treatment, or living with a kidney transplant.

The questionnaire consists of 36 self-report items and integrates two complementary components:

  • General Health-Related Quality of Life, assessed through the SF-12 Health Survey, which measures physical and mental health status.
  • Kidney Disease-Specific Domains, evaluating the unique burden of chronic kidney disease on patients’ everyday functioning, emotional well-being, symptoms, treatment burden, and satisfaction with care.

The KDQOL-36 examines several important dimensions of patients’ experiences, including:

  • Physical Health, evaluating physical functioning, fatigue, pain, and limitations in everyday activities.
  • Mental and Emotional Health, assessing emotional well-being, psychological distress, depression, anxiety, and overall mental functioning.
  • Burden of Kidney Disease, measuring the perceived impact of kidney disease on independence, lifestyle, family life, and daily responsibilities.
  • Symptoms and Problems, evaluating the frequency and severity of symptoms commonly experienced by patients with chronic kidney disease.
  • Effects of Kidney Disease on Daily Life, examining how the disease influences work, social relationships, mobility, and quality of life.
  • Patient Satisfaction and Treatment Experience, assessing perceptions of treatment effectiveness, healthcare services, and disease management.

Because the questionnaire combines generic and disease-specific health measures, it provides a comprehensive evaluation of patients’ overall quality of life while capturing the unique challenges associated with chronic kidney disease.

The KDQOL-36 is extensively used in nephrology, renal medicine, nephrology nursing, transplantation medicine, dialysis centers, rehabilitation, clinical trials, epidemiology, public health, and health services research, serving as an essential outcome measure for evaluating patient-centered care and treatment effectiveness.

Data Analysis and Use

The analysis of data obtained from the Kidney Disease Quality of Life-36 (KDQOL-36) involves comprehensive psychometric and statistical procedures designed to evaluate the multidimensional impact of chronic kidney disease on patients’ quality of life. Participant responses are transformed into standardized quantitative scores representing both generic health status and kidney disease-specific quality of life domains.

Psychometric evaluation includes the assessment of internal consistency, typically measured using Cronbach’s alpha coefficient, together with test–retest reliability, construct validity, criterion validity, content validity, and exploratory and confirmatory factor analyses to verify the multidimensional structure of the questionnaire.

Additional psychometric analyses frequently include item-total correlations, composite reliability, convergent validity, discriminant validity, predictive validity, responsiveness to clinical change, and cross-cultural measurement invariance, ensuring reliable assessment across different clinical populations and healthcare settings.

Statistical analyses commonly include descriptive statistics, calculation of means and standard deviations, correlation analyses, multiple regression models, multivariate analyses, repeated-measures analyses, structural equation modeling (SEM), longitudinal follow-up studies, and comparative analyses evaluating differences according to age, disease stage, dialysis modality, kidney transplantation, treatment duration, comorbidities, and healthcare interventions.

The KDQOL-36 is widely applied in nephrology clinics, dialysis units, transplantation programs, clinical trials, quality improvement initiatives, and health outcomes research. The findings assist clinicians in identifying patients experiencing reduced quality of life, tailoring individualized treatment strategies, monitoring disease progression, evaluating therapeutic interventions, and optimizing multidisciplinary patient care.

Objective

The primary objective of the Kidney Disease Quality of Life-36 (KDQOL-36) is to provide a reliable, valid, and comprehensive assessment of health-related quality of life in individuals living with chronic kidney disease. The questionnaire enables nephrologists, nurses, psychologists, researchers, and other healthcare professionals to evaluate how kidney disease and its treatment influence patients’ physical functioning, emotional well-being, social participation, and overall daily life.

The instrument facilitates the identification of patients experiencing substantial physical, emotional, or psychosocial burden while supporting individualized treatment planning and patient-centered clinical care. It also enables researchers to evaluate treatment effectiveness, compare therapeutic approaches, monitor longitudinal changes in patient outcomes, and assess the impact of healthcare interventions on quality of life.

The KDQOL-36 is particularly valuable in nephrology, renal replacement therapy, kidney transplantation, public health, epidemiology, nursing, rehabilitation medicine, behavioral medicine, and clinical research, where standardized assessment of patient-reported outcomes contributes to evidence-based healthcare and improved long-term patient management.

Scoring

The Kidney Disease Quality of Life-36 (KDQOL-36) consists of 36 self-report items, with responses primarily recorded using Likert-type response scales. Individual items are scored according to standardized KDQOL-36 scoring procedures and transformed into 0–100 standardized scores, allowing direct comparison across subscales.

The questionnaire generates scores for both the generic SF-12 health domains and the kidney disease-specific subscales, providing a comprehensive profile of patients’ health-related quality of life.

Higher scores generally indicate better perceived health status, fewer disease-related symptoms, lower treatment burden, improved physical and emotional functioning, greater social participation, and better overall quality of life, whereas lower scores reflect greater symptom burden, poorer physical and psychological functioning, increased disease impact, and reduced health-related quality of life.

The KDQOL-36 is particularly useful for monitoring changes over time, comparing different treatment modalities, evaluating rehabilitation outcomes, and assessing the effectiveness of interventions designed to improve the well-being of patients with chronic kidney disease.

Interpretation of questionnaire results should be supported by comprehensive psychometric evaluation, including Cronbach’s alpha coefficients, construct validity, factor analysis, criterion validity, responsiveness, and cross-cultural validation, ensuring reliable assessment across diverse clinical populations.

References

Hays, R. D., Kallich, J. D., Mapes, D. L., Coons, S. J., & Carter, W. B. (1994). Development of the Kidney Disease Quality of Life (KDQOL) Instrument. Quality of Life Research, 3(5), 329–338.

Cameron, J. I., Whiteside, C., Katz, J., & Devins, G. M. (2000). Differences in Quality of Life Across Renal Replacement Therapies: A Meta-Analytic Comparison. American Journal of Kidney Diseases, 35(4), 629–637.

Peipert, J. D., Bentler, P. M., Klicko, K., & Hays, R. D. (2018). Psychometric Properties of the Kidney Disease Quality of Life 36-Item Short Form Survey (KDQOL-36) in the United States. American Journal of Kidney Diseases, 71(4), 461–468.

Ware, J. E., Kosinski, M., & Keller, S. D. (1996). A 12-Item Short-Form Health Survey: Construction of Scales and Preliminary Tests of Reliability and Validity. Medical Care, 34(3), 220–233.