“…Since the positive hyphaema treatment results, referred to in the introduction, are calculated from combined prospective/retrospective materials with varying degrees of physical activities in the different parts of the studies, (Bramsen 1976(Bramsen , 1977(Bramsen , 1979 and from materials including patients with sickle cell trait, (Crouch & Frenkel 1976), these results all seem to be based on patient materials, being less equivalent than the present material.…”