ICPC AS A STANDARD CLASSIFICATION IN NORWAY

Background. The International Classification for Primary Care (ICPC) h as been the standard classification for diagnoses on sickness certific ates and bills for services to the National Insurance Administration i n Norway since 1992. Coding according to ICPC is compulsory for all ge neral practitioners. Objective. The objective of the present study was to describe the introduction of ICPC in Norway, to comment on introdu ction problems, and to examine the compliance and validity of coding. Methods. The study was based on statistics for episodes of sickness ce rtification in the National Benefit Absence Register. Results. In 1994 , the underlying medical diagnosis was coded in 98% of the sickness ab sence episodes lasting more than 2 weeks. Component 1 codes (symptom c odes) were used in 23% of episodes, compared with 26-31% in practice s tudies. Conclusions. ICPC-coded data in a large Norwegian register app ear promising. Most doctors do accurate and careful work in coding, an d data appear to be of acceptable quality for further analysis. It is a matter of concern, however, that as many as 23% of episodes had comp onent 1 codes, since these certificates were issued during follow-up e ncounters. The introduction of ICPC coding has enabled researchers to use diagnoses in the analyses of sickness absence. The growing use of ICPC in general practice has made multi-practice studies possible. The introduction of criteria is mandatory for the improvement of validity in diagnostic coding.