Affordable Access

Publisher Website

Reliability and Validity of the NIDDK-QA Instrument in the Assessment of Quality of Life in Ambulatory Patients With Cholestatic Liver Disease

Wiley Blackwell (John Wiley & Sons)
Publication Date
DOI: 10.1053/jhep.2000.19067
  • Medicine


Abstract The NIDDK-QA instrument, developed and widely used in liver transplant recipients, assesses quality of life (QOL) in four domains, including liver disease symptoms, physical function, health satisfaction, and overall well-being. We investigated whether the instrument may be used as a disease-specific instrument in ambulatory patients with cholestatic liver disease. The NIDDK-QA instrument was administered in 96 patients with primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) seen at the Mayo Clinic. The SF-36, a well-established generic instrument, was also administered. Standard measures for test-retest reliability, internal consistency, and discriminant and concurrent validity were examined. All patients were ambulatory with mostly normal levels of serum bilirubin and albumin concentrations. The reliability of the NIDDK-QA, as measured by test-retest correlation (Pearson coefficients: 0.82-0.99, P < .01) and by internal consistency (Cronbach's alpha: 0.87-0.94) exceeded conventional acceptability criteria. The correlation between domain scores of the NIDDK-QA and SF-36 was clear and logical in that the physical function domain of NIDDK-QA strongly correlated with the physical component summary score of SF-36 ( r = 0.86, P < .01). The overall well-being domain of the NIDDK-QA was closely associated with the mental summary score of SF-36 ( r = 0.69, P < .01). Among PBC patients, there was a modest yet significant correlation between the Mayo risk score and overall well-being ( r = −0.26, P = .03). In the assessment of QOL in patients with cholestatic liver disease, NIDDK-QA is found reliable and valid. These data, combined with our previous study, demonstrate its applicability in a wide spectrum of disease severity, ranging from early, ambulatory-phase disease to decompensated cirrhosis necessitating liver transplantation. (Hepatology 2000;32:924-929.)

There are no comments yet on this publication. Be the first to share your thoughts.