Feasibility, acceptability, and tolerability of operation calm: a mixed-methods evaluation with children, parents, and clinicians

Background Anxiety related to medical and dental procedures is common in childhood. Brief, portable interventions that combine immersive virtual reality (VR), mindfulness, and nature exposure may help children practice self-regulation, but the feasibility, acceptability, and tolerability of Operation Calm require evaluation before clinical efficacy testing. Methods This protocol describes a community-based, single-arm, dynamic mixed-methods pre–post feasibility study. Approximately 50 children and adolescents aged 6–17 years, up to 50 parents or legal guardians, and 50 pediatric clinicians or supervised trainees will be recruited across Canada. Children will complete one approximately 10-minute self-guided Operation Calm session using a smartphone-compatible VR headset and one of five 360° nature scenes paired with standardized mindfulness narration. Parents and clinicians will review one scene in an approved web-based format. Primary domains are recruitment and procedural feasibility, acceptability, engagement, usability, appropriateness, perceived usefulness, implementation feasibility, and child tolerability. Children will complete the Children's Anxiety Meter–State and a current calmness rating immediately before and after VR, the Pediatric Simulator Sickness Questionnaire after VR, and a child evaluation. Parents and clinicians will complete group-specific evaluations with quantitative and open-ended items. Results Feasibility and evaluation outcomes will be summarized descriptively with transparent denominators and confidence intervals where informative. Exploratory paired pre–post changes in child anxiety and calmness will be analyzed using paired-samples t tests or Wilcoxon signed-rank tests, with effect sizes and confidence intervals. Open-ended responses will undergo qualitative content analysis, and quantitative and qualitative findings will be integrated using a convergent mixed-methods approach. Scene-level profiles will be descriptive rather than confirmatory. Conclusions This early-stage study will determine whether Operation Calm can be delivered safely and consistently outside hospital care and identify refinements needed before a clinical feasibility study or randomized trial. Immediate pre–post changes will be interpreted as exploratory and will not establish efficacy. Clinical Trial Registration https://clinicaltrials.gov , ClinicalTrials.gov NCT07694934.