Despite the presence of considerable research on techniques for reducing distress associated with childhood hospitalization, few studies have examined the more basic issue of whether the event negatively affects children after discharge. A meta-analysis was conducted of studies using the Posthospital Behavior Questionnaire (the most commonly used method of examining posthospital behavior) to determine whether hospitalization results in negative behavioral change, the duration of this reaction, if detected, and factors potentially related to its strength. The mean weighted effect size was +.29 (Confidence Interval .95 = ± .07). Thus, in the absence of interventions, negative behavior tends to increase significantly after discharge (z= +3.99;p< .00006). However, this response diminishes with time and has largely disappeared after 2 weeks. Contrary to expectations, neither age of subjects nor their medical condition was related to their degree of upset. Subjects hospitalized for periods of 2 to 3 days exhibited more behavioral distress than did those hospitalized for either shorter or longer periods.J Dev Behav Pediatr 14:28–35, 1993.Index terms:hospitalized child, stress, psychological adaption, children, child behavior, hospitalization.