[Is severity related to the utilization of resources? An exploration of the Duke Severity of Illness Scale (DUSOI)]

To measure the distribution of the seriousness of illnesses and patients in primary care with the Duke Severity of Illness Scale (DUSOI) and relate it to resource use.

Observational prospective study.

Eight primary care centres from the centre sub-section of the Catalan Health Service.

For the first two months of the study, patients who attended for consultation at 9 general/family doctors' clinics were systematically sampled. 1,868 patients were selected and observed for 6 months.

The DUSOI was used to work out the seriousness of the illness and of the patient. The variables used as indicators of the use of resources for an illness were: the number of attendances, the time and costs of care. The same for the patient were: the number of attendances, number of episodes and costs of care. The average score for the seriousness of the episode was 31.4 with a standard deviation (SD) of 16.4. The correlations between use of resources and seriousness were under 0.4. The seriousness of the patient had an average of 44.9 (SD 21.3) and statistically significant correlations above 0.6 with the use of resources.

The seriousness of the illnesses attended in primary care is low and is related moderately to the use of resources. DUSOI could be better employed in research, inasmuch as there are systems for classifying patients which have greater explanatory power and can be constructed from pre-existing data.