Trends in diagnosis over a 10-year period in a Swedish primary care district.

In a study that covers ten years, the panorama of diagnosis was studied at three health centres in a Swedish primary care district with the aid of an encounter form. Frequencies for the different diagnosis groups varied considerably. In the case of malignant tumours, diseases of the thyroid, other endocrine diseases, symptoms and check-up visits there were more than 3-fold differences in diagnosis frequencies between various years. The results for individual years, therefore, were not representative of diagnosis distribution in the long-term perspective. Both systematic changes and temporary fluctuations occurred during the period. There was no evident lowest common denominator for the six diagnosis groups that increased (benign tumours, diseases of the thyroid and symptoms) or decreased (urinary tract infections, other urogenital diseases and back complaints). Although frequencies for individual diagnosis groups varied sharply from year to year, the diagnosis panorama in its entirety did, however, not change decisively. Permanent district physicians took charge mainly of the chronically ill, while other doctors were more involved with acute illness. It can be concluded that with such a varied diagnosis panorama in primary care it is difficult, based on temporary statistics from individual health centres, to draw general conclusions about the composition of patients. Thus, reliable figures on diagnosis should probably be founded on continuous registration at each clinic rather than on data collected periodically from especially selected reference centres.