Growth Hormone Response to Apomorphine-Reply

Reply.— Dr Ferrier and his colleagues emphasize the fact that a sex difference in the growth hormone response to apomorphine has been previously reported and they argue that this is a likely explanation of our findings. In reply, we would stress two points. First, we reported a difference not only between "Schneider-positive" and "Schneider-negative" psychotic patients but also between "Schneiderpositive" patients and control subjects matched for both age and sex. The differences between controls and these patients therefore cannot be solely attributed to sex differences. Second, age, sex, and diagnosis each contribute to the growth hormone response, and these factors may interact in quite complex ways, but the small number of subjects studied precluded appropriate statistical analysis of these interactions. In the light of these results, we have extended our studies to include many more drug-free psychotic patients. We can confirm, as emphasized by Ferrier and colleagues, that the