2. Overall study design
Participants were interviewed about their cancer-related PTSS and
underwent magnetic resonance imaging (MRI) at baseline. Participants
then completed four, 60-minute in-person KKC classes, following the
aforementioned standard procedures. KKC is a MAT that has been shown to
lower pain and emotional distress in pediatric cancer and other
populations, e.g., sickle cell, schoolchildren, adults with opioid use
disorder [11,18,19]. PTSS were re-assessed following the completion
of the four classes (Figure 1a ).
Cancer-related PTSS
We computed an overall PTSS severity score at baseline and
post-intervention, then change scores were computed to indicate response
to intervention, i.e., PTSS at baseline minus post-intervention, such
that higher scores indicate greater reductions in PTSS over time. PTSS
subtypes (i.e., re-experiencing, avoidance, negative affect,
hyperarousal) were also examined.
Gray matter volume analysis
See supplemental material.
Statistical Analyses
Related-Samples Wilcoxon Signed Rank Test was used to test for
within-subjects significant changes in PTSS over time (baseline vs.
follow-up). Regressions were used to examine whether baseline
hippocampal volumes were associated with baseline PTSS or PTSS change
scores, adjusting for total intracranial volume. Overall PTSS and
subtypes were examined. Follow-up analyses were conducted to test for
specificity of results to gray matter (GM) vs. white matter (WM). All
analyses were performed in SPSS v.27.0 [22] atp <0.05 (two-tailed).