Slaapmiddelen en karaktertype

Before the war the Institute of Praeventive Medicine issued an inquiry about the personal use of narcotics by physicians, part of it regarding the influence of the character. The scheme of Heymans and Wiersma being considered most apt to render characterising numbers, questions were included to diagnose whether "activity", "emotionality" and/or "secondary function" are present. Statistical analysis of the returns from 1593 physicians, shows that emotionality highly enlarges the use of narcotics (not only by the fact that it is combined with more disturbances in sleep). Activity showed no influence, whereas it is possible that secondary function stimulates the use in a small degree. The different types of character act by their different amount of these three qualities only.