RT Journal Article SR Electronic T1 Validation of an algorithm for identifying MS cases in administrative health claims datasets JF Neurology JO Neurology FD Lippincott Williams & Wilkins SP e1016 OP e1028 DO 10.1212/WNL.0000000000007043 VO 92 IS 10 A1 William J. Culpepper A1 Ruth Ann Marrie A1 Annette Langer-Gould A1 Mitchell T. Wallin A1 Jonathan D. Campbell A1 Lorene M. Nelson A1 Wendy E. Kaye A1 Laurie Wagner A1 Helen Tremlett A1 Lie H. Chen A1 Stella Leung A1 Charity Evans A1 Shenzhen Yao A1 Nicholas G. LaRocca A1 on behalf of the United States Multiple Sclerosis Prevalence Workgroup (MSPWG) YR 2019 UL http://n.neurology.org/content/92/10/e1016.abstract AB Objective To develop a valid algorithm for identifying multiple sclerosis (MS) cases in administrative health claims (AHC) datasets.Methods We used 4 AHC datasets from the Veterans Administration (VA), Kaiser Permanente Southern California (KPSC), Manitoba (Canada), and Saskatchewan (Canada). In the VA, KPSC, and Manitoba, we tested the performance of candidate algorithms based on inpatient, outpatient, and disease-modifying therapy (DMT) claims compared to medical records review using sensitivity, specificity, positive and negative predictive values, and interrater reliability (Youden J statistic) both overall and stratified by sex and age. In Saskatchewan, we tested the algorithms in a cohort randomly selected from the general population.Results The preferred algorithm required ≥3 MS-related claims from any combination of inpatient, outpatient, or DMT claims within a 1-year time period; a 2-year time period provided little gain in performance. Algorithms including DMT claims performed better than those that did not. Sensitivity (86.6%–96.0%), specificity (66.7%–99.0%), positive predictive value (95.4%–99.0%), and interrater reliability (Youden J = 0.60–0.92) were generally stable across datasets and across strata. Some variation in performance in the stratified analyses was observed but largely reflected changes in the composition of the strata. In Saskatchewan, the preferred algorithm had a sensitivity of 96%, specificity of 99%, positive predictive value of 99%, and negative predictive value of 96%.Conclusions The performance of each algorithm was remarkably consistent across datasets. The preferred algorithm required ≥3 MS-related claims from any combination of inpatient, outpatient, or DMT use within 1 year. We recommend this algorithm as the standard AHC case definition for MS.AHC=administrative health claims; CI=confidence interval; DMT=disease-modifying therapy; ICD-9=International Classification of Disease, 9th revision; ICD-9-CM=International Classification of Disease, 9th revision, clinical modification; ICD-10-CA=International Classification of Disease, 10th revision, Canadian version; ICD-10-CM=International Classification of Disease, 10th revision, clinical modification; IMS=Intercontinental Marketing Services; IP=inpatient; KPSC=Kaiser Permanente Southern California; MS=multiple sclerosis; NPV=negative predictive value; OP=outpatient; PPV=positive predictive value; VA=Department of Veterans Affairs