Early diagnosis of scoliosis based on school-screening.

A total of 8165 schoolchildren were screened for scoliosis by two teams of orthopaedic surgeons using the same procedures and criteria. Of 790 children who had positive physical signs, 689 were examined roentgenographically. Using 5 and 10 degrees as cut-off points, the prevalence of scoliosis was 6.58 and 2.4 per cent, respectively. A follow-up study of children who had been reported to have scoliosis at the age of eleven months showed that only half of them actually had scoliosis.

On the mathematical theory of globally optimal planned economic systems.

Applying a theorem of non-negative matrix to an economic system, we obtain the rate of growth of the system and the ratio between the sectors of production. Accordingly, we establish a positive eigenvector method for planning economics.