Development and Performance of an Algorithm to Estimate the Child-Turcotte-Pugh Score From a National Electronic Healthcare Database

Abstract

BACKGROUND & METHODS The Child-Turcotte-Pugh (CTP) score is a widely used and validated predictor of long-term survival in cirrhosis. The CTP score is a composite of 5 subscores, 3 based on objective clinical laboratory values and 2 subjective variables quantifying the severity of ascites and hepatic encephalopathy. To date, no system to quantify CTP score from administrative databases has been validated. The Veterans Outcomes and Costs Associated with Liver Disease study is a multicenter collaborative study to evaluate the outcomes and costs of hepatocellular carcinoma in the U.S. Veterans Health Administration. We developed and validated an algorithm to calculate electronic CTP (eCTP) scores by using data from the Veterans Health Administration Corporate Data Warehouse. METHODS Multiple algorithms for determining each CTP subscore from International Classification of Diseases version 9, Common Procedural Terminology, pharmacy, and laboratory data were devised and tested in 2 patient cohorts. For each cohort, 6 site investigators (Boston, Bronx, Brooklyn, Philadelphia, Minneapolis, and West Haven VA Medical Centers) were provided cases from which to determine validity of diagnosis, laboratory data, and clinical assessment of ascites and encephalopathy. The optimal algorithm (designated eCTP) was then applied to 30,840 cirrhotic patients alive in the first quarter of 2008 for whom 5-year overall and transplant-free survival data were available. The ability of the eCTP score and other disease severity scores (Charlson-Deyo index, Veterans Aging Cohort Study index, Model for End-Stage Liver Disease score, and Cirrhosis Comorbidity) to predict survival was then assessed by Cox proportional hazards regression. RESULTS Spearman correlations for administrative and investigator validated laboratory data in the HCC and cirrhotic cohorts, respectively, were 0.85 and 0.92 for bilirubin, 0.92 and 0.87 for albumin, and 0.84 and 0.86 for international normalized ratio. In the HCC cohort, the overall eCTP score matched 96% of patients to within 1 point of the chart-validated CTP score (Spearman correlation, 0.81). In the cirrhosis cohort, 98% were matched to within 1 point of their actual CTP score (Spearman, 0.85). When applied to a cohort of 30,840 patients with cirrhosis, each unit change in eCTP was associated with 39% increase in the relative risk of death or transplantation. The Harrell C statistic for the eCTP (0.678) was numerically higher than those for other disease severity indices for predicting 5-year transplant-free survival. Adding other predictive models to the eCTP resulted in minimal differences in its predictive performance. CONCLUSION We developed and validated an algorithm to extrapolate an eCTP score from data in a large administrative database with excellent correlation to actual CTP score on chart review. When applied to an administrative database, this algorithm is a highly useful predictor of survival when compared with multiple other published liver disease severity indices.

A Comparative Study of Albumin-Bilirubin Score with Child-Pugh Score, Model for End-Stage Liver Disease Score and Indocyanine Green R15 in Predicting Posthepatectomy Liver Failure for Hepatocellular Carcinoma Patients

“…Recently, some flaws of the Child-Pugh score have been proposed [4, 5, 25]. First, some indexes included in the Child-Pugh score are interrelated, such as ascites and serum albumin level.…”

“…The Child-Pugh grade has been used to predict the short-term and long-term outcomes of HCC patients undergoing hepatic resection for years. However, some drawbacks of the Child-Pugh grade have been described recently [4, 5]. The MELD score was mainly used to assess the prognosis of chronic liver diseases and apply for the allocation of donor livers [6, 7], and was thereafter developed to predict postoperative outcomes for patients undergoing hepatic resection [8].…”

The Child–Turcotte Classification: From Gestalt to Sophisticated Statistics and Back

“…More importantly, Kaplan et al in this and a previous study (6, 7), have made great strides in defining the two CTP clinical variables, ascites and encephalopathy, aspects of the CTP classification that have been considered its major shortcoming because they are subjective and are confusing not only in the stratification of patients in clinical trials but even more challenging when analyzing administrative databases.…”

“…Therefore, the strategy adopted by Kaplan et al (6, 7) was to take a longitudinal view of these clinical variables so as to faithfully represent the clinical staging of cirrhosis with well-defined prognostic implications (8). For ascites, a CTP score of 3 is assigned to patients with refractory ascites requiring frequent large volume paracentesis or TIPS as well as patients with a history of spontaneous bacterial peritonitis; a score of 2 is assigned to patients requiring diuretic therapy for control of ascites but without any of the previously mentioned complications.…”

Reply to Risk Stratification in Acute Variceal Bleeding: Child-Pugh Versus Model for End-stage Liver Disease

“…Recently, these “subjective” variables could be successfully obtained retrospectively using a large administrative database that showed an excellent survival discrimination among the 3 different CTP classes and, in fact, showed a better prognostic value than MELD which only discriminated 1–5-year outcomes accurately in patients with a CTP score >11 3 . Not including decompensating events (mainly ascites) in a model, does not allow for proper stratification of patients into the two main prognostic stages of cirrhosis, compensated and decompensated.…”