Abstract: | We have classified patients referred for suspicion of the Brachmann–De Lange syndrome (BDLS) into two groups using techniques of numerical taxonomy. Patients with the syndrome share an array of abnormal characteristics, and those without it have different abnormal characteristics. A group of 30 characters that best distinguish the two groups of patients was used to construct a diagnostic index. The index score is expected to divide 99% of patients into those with and without the syndrome, leaving 1% in a “zone of doubt.” All 46 patients used to construct the index and 16 new patients had scores in either the BDLS or non-BDLS range and none were in the zone of doubt. A previously published index using metacarpal-phalangeal measurements, although less discriminatory, confirmed our findings in 84% of 25 patients tested, the remainder having scores in the zone of doubt for that index. |