Quantitative liver function tests as surrogate markers for end-points in controlled clinical trials: A retrospective feasibility study

摘要: Quantitative liver function tests such as the determination of galactose elimination capacity (GEC) or aminopyrine breath test (ABT) may have potential to serve refined entry criteria and surrogate markers for end-points in controlled clinical trials. The magnitude a statistically detectable difference results period observation required document must be known properly design Therefore, we explored retrospectively time course changes GEC ABT their reproducibility from cohort patients with alcoholic cirrhosis followed 12 42 months, median 34 months. In 15 who stopped drinking, improved significantly by 0.64 mg/min/kg within 1 year (mean; 95% confidence interval [CI]: 0.42; 0.86). contrast, it deteriorated 0.53 (95% CI: 0.32; 0.74) another 17 continued drink (P < .01). residual standard deviation respect patients' initial values was 0.43 0.52). addition, 0.14% dose · kg/mmol CO2 0.09; 0.18) abstinent group, 0.09% 0.06; 0.13) nonabstinent group above sense 0.08% 0.10). These data indicate that trials sample size n = 20 each achieve absolute differences (ADs) 0.6 0.7 reach statistical significance at 5% 1% level, respectively. present study, 11 months necessary observe differences. corresponding are 0.11% (9 follow- up; level) 0.13% (11 observation; level), Provided diseases treated drugs similar disease investigated this numbers could planning trials, which control is likely deteriorate expected improve. Trials based on would require only 37 30 patient years compared 444 (range, 50-2,100 years) reported various published using survival analysis.