Table 2: Estimated rate of change per year for MED and DBS + MED groups.

Before DBS (Estimate (SE)) After DBS (Estimate (SE)) P-value*
MED only 61.14 (54.07) 93.48 (45.94) 0.6642
DBS + MED 61.14 (54.07) -170.34 (62.74) 0.0172
Average daily cost in US dollars:
MED only 1.34 (0.90) 1.39 (0.92) 0.9662
DBS + MED 1.34 (0.90) -2.93 (1.38) 0.0199

Annual rate of changes and their standard errors are estimated based on the Mixed Effects model described in the Statistical Analysis section, and p-values are for testing the null hypothesis that the estimated rates are the same before and after “date of DBS.” For MED patients, the “date of DBS” represents the date at which they would have DBS, based on the timing of surgical intervention in their DBS + MED group counterparts.