Statistical Analysis Methods
Depression, seizure, APS, epilepsy
APS, EPILEPSY, ADVERSE EVENTS, SECONDARY, EPILEPSY
Two analysis sets were used in this study: all patients set (APS) consisted of all enrolled patients and full analysis set (FAS) consisted of patients of the APS who met all eligibility criteria and were implanted with DBS therapy for epilepsy following the intent to treat (ITT) principle. APS was used for safety analysis and FAS for assessing the primary effectiveness objective, that is, the relative change in monthly SF at 2 years postimplant, and secondary effectiveness objectives including Quality of Life in Epilepsy 31-item questionnaire (QOLIE-31) and Beck Depression Inventory II (BDI-II) scores. No missing data imputation was used for the analyses of primary and secondary objectives. The patients were categorized into 3 groups based on the seizure reduction (SR) at 2 years of follow-up: responders (≥50% SR), improvers (50% > SR > 0%), and no-benefit patients (SR ≤0%).Baseline and follow-up data were summarized using appropriate summary statistics. Although no formal hypothesis testing was defined for this study, Safety data were summarized using descriptive statistics. In addition, adverse events were reported per study period; for each period, the available patient set was used. All analyses were performed using SAS software (version 9.4; SAS Institute, Cary, NC).