The effect of recombinant human growth hormone (rhGH) treatment on the quality of life was studied in adults with growth hormone deficiency (GHD). Twenty-four adults who satisfied strict criteria for GHD took part in a double-blind, placebo-controlled, 6-month trial. 'Quality of life' assessment was performed at entry into the trial and after 1 month and 6 months, by means of self-rating questionnaires. Entry data were also compared with a control group of healthy subjects matched for age, gender, ethnic origin, socio-economic class and area of residence. Significantly lower scores on 'quality of life' assessment in the growth hormone (GH) deficient patients were reported at entry into the trial compared with matched controls, indicating that patients with GHD may be psychologically compromised. Preliminary analysis of the results shows that after 6 months patients receiving human growth hormone (hGH) treatment experienced less perceived illness than the placebo group. Significant psychological improvement was noted in the hGH-treated patients' perception of their energy level and mood compared to the placebo group.