IN RECENT YEARS there has been considerable interest in the effects of hospitalization and illness on children, particularly in those indications of psychological upset which outlast the period of hospitalization itself. Most investigators have relied primarily on the incidence (or changes in the incidence) of various "symptoms" for their measures of posthospital reactions, eg, enuresis, refusal to eat, night terrors, and temper tantrums. However, the relationships among symptoms have been ignored. For example, those who have combined data on particular symptoms into global measures of psychological upset (eg, Eckenhoff1) have not considered the homogeneity (or internal consistency) of such measures. Similarly, investigators who have distinguished subgroups of symptoms representing behavioral syndromes or types of responses (eg, Jackson et al2) have neither examined the actual relationships (eg, the correlations) among symptoms nor used such data in systematic analyses designed to distinguish subgroups of symptoms. The authors of the present