Virtual reality-delivered exposure for contamination concerns in adults with obsessive-compulsive symptoms: a single-arm pilot study
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
Background: Exposure and response prevention is a first line intervention for obsessive compulsive disorder (OCD), yet many individuals with contamination concerns do not access care. Virtual reality exposure (VRET) may improve scalability and acceptability.
Objective: This pilot study evaluated the feasibility and acceptability of a standardized single-session VRET protocol targeting contamination concerns, whether it elicited within-session anxiety and exploratory contamination symptom change at 1-month follow-up.
Methods: We conducted a single-arm, pilot in adults with elevated contamination concerns and no formal OCD diagnosis, recruited via convenience sampling. Participants completed a baseline survey, an in-lab VRET session using a standardized virtual public toilet environment, and a follow-up survey. Outcomes included momentary anxiety (Subjective Units of Distress Scale) during exposure, affect (Positive and Negative Affect Schedule) across time points, and contamination symptoms (Obsessive Compulsive Inventory Revised contamination subscale) at baseline and follow-up. Usability (System Usability Scale; SUS) and VR sickness were also assessed. Within-session outcomes used repeated-measures ANOVA or Friedman tests; symptom change used paired t tests (alpha = .05); point estimates include 95% CIs. Missing data were addressed using multiple imputation (random forest; m = 5); 37.5% of participants did not complete the follow-up survey (overall missingness: 5.47%).
Results: Sixteen participants were included (ages 18-32 years). Anxiety increased during exposure tasks and decreased after virtual hand washing in both trials (Exposure 1 Friedman’s Test: χ²(3) = 28.56, P < .001, W = 0.6); Exposure 2 repeated measures ANOVA: F(1.85, 27.81) = 5.35, P = .012, GES = 0.058 (Greenhouse-Geisser corrected). Negative and positive affect both changed significantly across time points (negative affect: Friedman’s Test: χ²(3) = 13.76, P = .003, W = 0.29); positive affect: repeated measure ANOVA: F(3, 45) = 4.60-4.71, P = .006-.007, GES = 0.07-0.073). Contamination symptoms did not significantly change from baseline to follow up (mean change 1.30, 95% CI -0.36, 2.96; P=.124). Usability was adequate (SUS mean 69.5, 95% CI 62.79, 76.21).
Conclusions: This study is among the first to systematically evaluate a standardized single-session contamination-focused VRET protocol in adults with elevated contamination concerns who did not meet diagnostic criteria for OCD, a subthreshold population underrepresented in prior VRET research, which has focused on clinically diagnosed samples and multi-session protocols. The protocol proved feasible and acceptable, eliciting within-session anxiety and providing benchmarks in existing clinical literature. Contamination symptom change at 1-month follow-up was not statistically significant, and the effect size estimate was sensitive to the missingness assumption, underscoring the need for adequately powered multi-session designs in future trials. The usability profile and VR sickness levels that did not prevent session completion suggest self-administered or minimally supervised delivery warrants evaluation, with implications for scalable early intervention in individuals with elevated contamination concerns who have not accessed formal treatment.
Objective: This pilot study evaluated the feasibility and acceptability of a standardized single-session VRET protocol targeting contamination concerns, whether it elicited within-session anxiety and exploratory contamination symptom change at 1-month follow-up.
Methods: We conducted a single-arm, pilot in adults with elevated contamination concerns and no formal OCD diagnosis, recruited via convenience sampling. Participants completed a baseline survey, an in-lab VRET session using a standardized virtual public toilet environment, and a follow-up survey. Outcomes included momentary anxiety (Subjective Units of Distress Scale) during exposure, affect (Positive and Negative Affect Schedule) across time points, and contamination symptoms (Obsessive Compulsive Inventory Revised contamination subscale) at baseline and follow-up. Usability (System Usability Scale; SUS) and VR sickness were also assessed. Within-session outcomes used repeated-measures ANOVA or Friedman tests; symptom change used paired t tests (alpha = .05); point estimates include 95% CIs. Missing data were addressed using multiple imputation (random forest; m = 5); 37.5% of participants did not complete the follow-up survey (overall missingness: 5.47%).
Results: Sixteen participants were included (ages 18-32 years). Anxiety increased during exposure tasks and decreased after virtual hand washing in both trials (Exposure 1 Friedman’s Test: χ²(3) = 28.56, P < .001, W = 0.6); Exposure 2 repeated measures ANOVA: F(1.85, 27.81) = 5.35, P = .012, GES = 0.058 (Greenhouse-Geisser corrected). Negative and positive affect both changed significantly across time points (negative affect: Friedman’s Test: χ²(3) = 13.76, P = .003, W = 0.29); positive affect: repeated measure ANOVA: F(3, 45) = 4.60-4.71, P = .006-.007, GES = 0.07-0.073). Contamination symptoms did not significantly change from baseline to follow up (mean change 1.30, 95% CI -0.36, 2.96; P=.124). Usability was adequate (SUS mean 69.5, 95% CI 62.79, 76.21).
Conclusions: This study is among the first to systematically evaluate a standardized single-session contamination-focused VRET protocol in adults with elevated contamination concerns who did not meet diagnostic criteria for OCD, a subthreshold population underrepresented in prior VRET research, which has focused on clinically diagnosed samples and multi-session protocols. The protocol proved feasible and acceptable, eliciting within-session anxiety and providing benchmarks in existing clinical literature. Contamination symptom change at 1-month follow-up was not statistically significant, and the effect size estimate was sensitive to the missingness assumption, underscoring the need for adequately powered multi-session designs in future trials. The usability profile and VR sickness levels that did not prevent session completion suggest self-administered or minimally supervised delivery warrants evaluation, with implications for scalable early intervention in individuals with elevated contamination concerns who have not accessed formal treatment.
Date Acceptance
2026-05-20
Citation
JMIR Serious Games
ISSN
2291-9279
Publisher
JMIR Publications
Journal / Book Title
JMIR Serious Games
Copyright Statement
Copyright This paper is embargoed until publication. Once published the Version of Record (VoR) will be available on immediate open access.
Publication Status
Accepted