Evaluation of clinical severity in sickle cell disease

For a severity classification of sickle cell disease to be accepted, it is necessary that clinicians agree upon relative disease severity between patients. This condition was shown to be satisfied for a randomly selected group of patients evaluated by four persons. All rank correlation coefficients between observer pairs were highly significant. Representative severity indices based on history and recent hospital events also correlated significantly with evaluator ranking. The results show that, in principle, a classification of sickle cell disease patients by severity is possible. Such a classification would be most useful to evaluate the prognostic significance of particular signs or symptoms, or the success of various treatments in affecting severity of disease.