There is ample empirical evidence supporting the view of emotional disturbances in children with recurrent abdominal pain (RAP) as well as in their parents. However, controlled studies have reported that such manifestations can also be found in patients with other chronic ailments. In order to characterize further the nature of emotional factors in RAP patients, we conducted a controlled psychological evaluation of 46 consecutive new patients with RAP, aged 7-17 years, (group A) by means of structured interviews and questionnaires. Two control groups of pediatric patients with chronic illnesses were also assessed using the same methodology. Group B consisted of 22 individuals with chronic abdominal pain and endoscopy-proven peptic ulcer or duodenitis, and group C consisted of 24 individuals with chronic, stable, non-gastroenterological diseases (e.g., diabetes mellitus or physical handicaps). Parents were evaluated for depressive symptoms. One-way analysis of variance and contingency tables were used for statistical comparisons. There was a higher proportion of female patients in group A than in group B (70 vs 41%; p < 0.05). There were significantly more patients in group A than in group B that reported that their abdominal pain: a) never appeared during sleep, b) began soon after the patient's arousal in the morning, c) remitted completely or was alleviated during school holidays, d) its remission was usually spontaneous during the day and e) did never interfere with recreational activities. Emotional problems were significantly more prevalent in patients in group B than in those in group A (p = 0.016). Past diagnosis of depression was more frequent in group A mothers (40%) than in those in group B (27%), or group C (17%), but these differences did not attain statistical significance. These results suggest that psychological profiles of children suffering from certain chronic conditions (and those of their parents) may be more complex and particular than hitherto recognized. The role of type II error and of some potential socioeconomic and demographic confounding factors must be considered when analyzing the validity of these data.