The relative efficacy and efficiency of single- and multi-session exposure therapies for specific phobia: A meta-analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of clinical intervention studies
PubMed 36323055 · doi:10.1016/j.brat.2022.104203
What was done
A systematic search of PsycINFO, Embase, MEDLINE, and Cochrane identified peer-reviewed studies assessing multi-session (k = 30) and single-session (k = 55) in vivo exposure therapy for specific phobia in clinical populations (n = 1758). A random-effects model synthesized and compared pre-to-post treatment effect sizes (Hedges' g) for approach behavior and self-reported symptoms at post-treatment and follow-up, with phobia subtype evaluated as a moderator.
What was found
Mean total treatment time was significantly longer for multi-session exposure than single-session exposure. There were no statistically significant differences in pooled effect sizes between single- and multi-session exposure at post-treatment or follow-up, with effect sizes classified as large for all outcomes. Phobia subtype significantly moderated effect sizes for both treatment formats, with association directions differing by outcome measure. Specific numerical effect sizes and confidence intervals were not reported in the abstract.
Why it matters
Single-session exposure provides symptom reduction and behavioral improvements comparable to multi-session formats while substantially reducing overall treatment duration. Facilitating access to single-session protocols could markedly increase efficiency in clinical settings.
Limits
The synthesis compares pooled pre-post effect sizes across study arms rather than exclusively pooling direct head-to-head randomized comparisons. Exact numerical effect sizes, dispersion metrics, and follow-up lengths are omitted from the abstract. Dropout rates, acceptability, and long-term durability beyond general follow-up were not reported.
Cited by
- supports Exposure reduces phobic fear and anxiety, whereas avoidance exacerbates fear.