Ranking of liver tests for differential diagnosis of liver parenchymal diseases.

Liver function tests were ranked in the order useful to differentiate 8 liver parenchymal diseases in combination of tests by forward selection and backward elimination procedures in the likelihood method using a microcomputer. The orders were almost same in both procedures: indocyanine green plasma disappearance rate, glutamic pyruvic transaminase (GPT), zinc turbidity test, alkaline phosphatase, age, HBsAg, RA test, glutamic oxaloacetic transaminase (GOT)/GPT ratio, GOT, cholesterol, total protein, total bilirubin, albumin/globulin ratio and gamma-globulin. The first 9 tests had almost all informations of all tests. The first likelihood diagnosis using the 9 tests was correct in 53% and the first or the second diagnosis was correct in 71% of 444 cases of 8 liver parenchymal diseases. A score table of likelihood diagnosis using the 9 tests was presented for manual application to new cases.