Statistical analysis
pre-DBS +
SECONDARY
Change scores for each secondary outcome measure were calculated individually across five separate time periods: pre-surgery versus post-surgery (month 1 minus consent), pre-rehab-only versus post-rehab-only (month 3 minus month 1), pre-DBS + rehab versus post-DBS + rehab (month 8–12 minus month 4), pre-rehab carryover versus post-rehab carryover (month +2 minus month 8–12) and post-DBS + rehab to end of long-term follow-up (month ‘+10’ versus month 8–12). Due to skewed distributions, change scores are summarized using medians with interquartile ranges. Wilcoxon signed-rank tests were used to test for a significant change at each time period by comparing change scores for each phase to zero. Descriptive statistics with confidence intervals, for the full sample and for the sample stratified by functional preservation at baseline, are presented in the Statistical analyses of PET data focused on the effect of therapy and its correlation with change in arm function per the AMAT (version 13). Linear mixed-effects models