Assessing outcomes in liver disease patients: reliability and validity of the Spanish version of the Liver Disease Quality of Life Questionnaire (LDQOL 1.0).

OBJECTIVE: To assess the reliability and validity of a Spanish version of the LDQOL 1.0 (Liver Disease Quality of Life questionnaire).
METHODS: Observational, cross-sectional study in Spanish patients awaiting liver transplantation (LT). Feasibility was assessed by analyzing administration times and missing responses. Ceiling and floor effects were calculated and reliability was tested by examining internal consistency (Cronbach's alpha). Convergent validity was tested by examining correlations between LDQOL disease-specific and Short Form health survey with 36 questions (SF-36) dimensions. Known groups' validity was tested by examining the LDQOL's capacity to discriminate between groups defined by etiology and Child-Turcotte-Pugh (CTP) scores.
RESULTS: A total of 200 patients were included for analysis. Mean age (SD) was 52.6 (9.8) years and 73% of the sample were male. The most common indication for LT was liver cancer (34%). Mean (SD) time to complete the questionnaire was 35.8 minutes (21.2 minutes). Missing responses were highest on the dimensions of sexual functioning and symptoms of liver disease. Ceiling effects were over 20% on 7 of the LDQOL's 12 disease-specific scales. Cronbach's alpha coefficients were over 0.70 on all but 2 dimensions. Correlations between SF-36 and LDQOL disease-specific dimensions generally fulfilled the hypotheses, with 35 of the 40 highest and lowest correlations (87.5%) being in the expected direction. The LDQOL discriminated well between patients in CTP class A and C, and as hypothesized, hepatocarcinoma and alcoholic cirrhosis patients scored better on most dimensions than patients with hepatitis C virus or other etiologies.
CONCLUSIONS: The Spanish version of the LDQOL 1.0 has shown satisfactory reliability and validity.