IQ, prognosis and Duchenne muscular dystrophy.

The verbal scales (VS-IQ) of the IQs of 25 boys with Duchenne muscular dystrophy, the total population in Western Australia older than five yrs, were recorded. All the results of those 20 yrs of age and older lay within the normal range. The mean VS-IQ of those less than 20 yrs and less than 18 yrs is compared with the mean VS-IQ of those 20 yrs and older, and 18 yrs and older, respectively. The differences between the groups are statistically significant, and it is postulated that an active management programme has revealed a population of boys with normal intelligence who have an increased chance of prolonged survival.