Background and aims-To develop and assess a disease specific instrument for measuring health related quality of life (HRQL) in patients with chronic liver disease (CLD). Methods-Based on responses from 60 patients with chronic liver disease, from 20 liver experts, and from a Medline search of the literature, items potentially aVecting the HRQL of these patients were identified. A separate sample of 75 patients identified which items they found problematic and rated their importance. Results were explored using factor analysis; domains were chosen and items placed within domains. Redundant questions were eliminated and the final questionnaire was pretested in 10 patients. Using this instrument, HRQL was assessed in a further 133 patients with various types and stages of liver disease. Results-Patients, experts, and the literature search identified 156 items of potential importance. Of these, 35 proved important to over 50% of 75 respondents in the item reduction sample. The factor analysis suggested six domains. After eliminating redundancies, the Chronic Liver Disease Questionnaire (CLDQ) included 29 items in the following domains: fatigue, activity, emotional function, abdominal symptoms, systemic symptoms, and worry. In pretesting, patients found the CLDQ clear and easy to complete in 10 minutes. In another 133 patients, the CLDQ showed a gradient between patients without cirrhosis, Child's A cirrhosis, and those with Child's B or C cirrhosis. CLDQ has evidence for moderate reliability at six months and seems to be responsive. Conclusion-The CLDQ is short, easy to administer, produces both a summary score and domain scores, and correlates with the severity of liver disease. (Gut 1999;45:295-300) Keywords: quality of life; liver disease; liver specific quality of life; well beingThe traditional "biomedical model" of health which is based on the basic sciences (molecular biology, genetics, physiology, biochemistry, etc.) is being integrated with the "social science model" of health, based on a psychosocial and economic foundation. This integrated approach to clinical practice and research in medicine requires not only monitoring the traditional physiological and biochemical outcomes but also health related quality of life (HRQL).

We conclude that chronic liver disease substantially reduces HRQL, and this impact does not differ markedly by type of disease. Older age and measures of disease severity were associated with poorer HRQL.

Patients with cholestatic liver disease (PBC and PSC) showed substantial impairment of HRQL, which is further affected by worsening disease severity. Disease-specific measures were better able to discriminate patients with varying severities.

Hepatitis C RNA testing has been used extensively to assess the efficacy of antiviral therapy and has increasingly become an integral part of clinical management of patients with chronic hepatitis C. A variety of commercially available hepatitis C virus (HCV) RNA tests are used to detect HCV RNA qualitatively or quantitatively. These commercial tests have fundamental differences that are reflected on the values they generate. We compared two widely used assays, HCV SuperQuant (SQ) and Amplicor HCV Monitor (M1 and M2), in sera of patients with chronic hepatitis C. A total of 506 sera from 79 patients were tested with both assays. The data were logarithmically transformed and analyzed by linear regression and measurement of agreement. Two hundred thirty-eight sera had HCV RNA values within the dynamic range of both assays. The correlation between the assays was fair, with a correlation coefficient (r) of 0.699. Overall, SQ generated higher values than M1 with a mean difference of 0.558 log (SD = 0.624). One hundred ninety-four (38%) and 121 (24%) of the sera were below the dynamic range of M1 and SQ, respectively. Seventy-three sera, undetectable by M1, were positive by SQ. The Amplicor HCV Monitor 2.0 (M2) was performed in 66 sera. All were positive by SQ and M2, but only 38 were within the dynamic range of M1. The correlations between these tests were good (r = 0.68-0.78), but the agreement was rather poor. In conclusion, this study confirms that both SQ and M2 are more sensitive than M1. Additionally, our results show rather poor agreements between these assays. The recent attempts in standardizing the reporting of these assays should make their results more easily interchangeable.