The effects of waiting time for outpatient psychotherapeutic interventions on patient-reported outcomes in adolescents and adults with eating disorders: a systematic review and meta-analysis.

内容摘要

To assess the effects of waiting time for outpatient psychotherapeutic interventions on patient-reported outcomes in adolescents and adults with eating disorders. MEDLINE, Embase, APA PsycInfo, CENTRAL and BASE were searched on 12 August 2025. Quantitative studies of adolescents (≥ 10 years) and adults with eating disorders that examined waitlist conditions prior to outpatient psychotherapeutic interventions and measured eating disorder pathology with the Children's Eating Attitudes Test (chEAT) or Eating Disorder Examination-Questionnaire (EDE-Q) were eligible. Risk of bias was assessed using the RoB 2 and ROBINS-I tools. A within-group random-effects meta-analysis was performed assessing pre-post change scores of the EDE-Q Global Score (primary analysis) and EDE-Q subscales (secondary analyses). A full protocol has been pre-registered on PROSPERO (registration number: CRD420251090691). Nine waitlist-controlled studies (total n = 647, waitlisted n = 283) including adult participants with bulimia nervosa, binge-eating disorder and 'eating disorder not otherwise specified' met our eligibility criteria. Eight studies (waitlisted n = 273) were included in the meta-analysis. Participants entered the waiting period with high EDE-Q Global Scores, ranging from 3.08 to 4.65 across studies. The pooled pre-post effect estimate was Hedges' g = - 0.17 (95% CI - 0.30 to - 0.05), indicating a negligible reduction in eating disorder pathology. Certainty of evidence was rated as moderate, given the high risk of bias across studies. Based on our results, waiting in waitlist control groups represents a period during which substantial eating disorder pathology and associated distress persist without therapeutic intervention. Further research is needed to better understand the effects of waiting time for regular eating disorder treatment outside a study setting. Study participants on a waitlist to be treated for bulimia nervosa, binge-eating disorder, and ‘eating disorder not otherwise specified’ continued to report high levels of eating disorder symptoms while waiting about 10 weeks for psychotherapy. This means that individuals may experience considerable distress during a delay in starting treatment. However, being on a study waitlist is not the same as waiting for treatment in everyday healthcare. In a study, participants know when and what kind of treatment they will get, which might already help reduce symptoms before treatment even starts. We could not find studies that assessed the effects of waiting time in everyday healthcare.