To the Editor We are writing in response to the Viewpoint by Olfson and colleagues,1 which recommended the establishment of the S-Index as an incentive to encourage researchers to share their data. The Viewpoint contains a thoughtful discussion of the tensions for an individual investigator to share data, and we agree that a fully implemented S-Index could encourage investigators to share their data. The National Institute of Mental Health Data Archive (NDA) has implemented features that provide much of the functionality of the proposed S-Index. A basic description of the forerunner of the National Institute of Mental Health Data Archive, the National Database for Autism Research, has been published.2 The NDA holds deidentified data from human patients. The types of data that are in the archive include clinical and phenotypic assessments, genomics data, magnetic resonance imaging data, and data from other complex experimental types. Data from more than 130 000 research participants are available to the research community via the NDA.
Novikova S, Hall D, Farber GK. The S-Index and the National Institute of Mental Health Data Archive. JAMA Psychiatry. 2017;74(5):540-541. doi:10.1001/jamapsychiatry.2017.0145