Diagnostic tests for alcoholism in primary health care: compared efficacy of different instruments

Alcoholism is an uncommon diagnosis in normal medical activity despite being a prevalent health problem in Spain. One of the main obstacles that make diagnosis difficult is the lack of valid, reliable instruments of detection. The aim of the present study is to validate different tests for diagnosing alcoholism (CAGE, Alcohol Clinical Index, MCV, GGT, GOT/GPT and GGT/AP) in primary care and compare their diagnostic efficacy.

The diagnostic efficacy and discriminating power of each of the tests were calculated from the results obtained from 219 patients (out of 698 aged over 15 years) who answered the CAGE questionnaire. Patients were selected from doctors surgeries in an urban health centre. The diagnosis of alcoholism was based on the presence of DSM-III criteria and/or a daily alcohol consumption of 60 grams or more in men and 30 or more in women.

The CAGE questionnaire showed a sensitivity of 69.86% and specificity of 80.46%, with the cut-off point at 1. The remaining tests showed a poorer diagnostic efficacy. The CAGE questionnaire scoring was the parameter that best distinguished alcoholic patients from non-alcoholic patients.

The CAGE questionnaire demonstrates the greatest efficacy and discriminating power for diagnosing patients with alcoholism in primary care.