Validity and Efficacy of Screening Algorithms for Assessing Deep Brain Stimulation Candidacy in Parkinson's Disease

DBS for Parkinson's disease (PD) may be underutilized because of limited access to care (most DBS surgeries are performed at specialized centers) or over-referral of poor candidates, leading to inequitable utilization of limited evaluative resources. There is a pressing need for a widely employable screening algorithm to aid in the evaluation of PD candidates for DBS. The aim of this study was to compare the validity and efficacy of two published screening algorithms, the Florida Surgical Questionnaire for PD and Stimulus, to predict candidacy for DBS. We reviewed the clinical data at our DBS center for 147 consecutive PD DBS referrals between 1 September 2007 and 31 December 2011. Florida Surgical Questionnaire and Stimulus scores were applied retrospectively through a chart review of the movement disorder neurologist's initial clinical evaluation. The validity and accuracy of these two algorithms in predicting candidacy for DBS was compared to the decision to offer DBS surgery by our multidisciplinary DBS team. Of the 130 consecutive PD referrals who presented for initial evaluation, 50 were offered DBS after a standardized multidisciplinary evaluation. The Stimulus scale was a superior screening tool for predicting PD DBS candidacy in these referrals (area under the receiver operating curve [AUROC] = 0.8088), compared to the Florida Surgical Questionnaire for PD (AUROC = 0.6285). In this single-center study, Stimulus was a more appropriate screening measure than the Florida Surgical Questionnaire for PD to assess DBS candidacy for PD.