To compare the preliminary efficacy of the intervention group across
time, GEE analyses were run for the overall sample comparing the primary
and secondary outcome variables from pre-treatment to posttreatment
and 3-month follow-up in the intervention group. An exchangeable
correlation matrixwas selected to reduce the cost of the degrees
of freedom needed from a relatively small sample size. Pairwise
contrasts were made to test additional symptom change between
post-treatment and 3-month follow-up.