Cognition Kit DSST App Validated for Measuring Major Depressive Disorder

The following article is a part of conference coverage from Psych Congress 2020 Virtual Experience, held virtually from September 10 to 13, 2020. The team at Psychiatry Advisor will be reporting on the latest news and research conducted by leading experts in psychiatry. Check back for more from the Psych Congress 2020.


The potential of a mobile app as a valid and easily accessible tool for measuring cognitive function in adults with major depressive disorder (MDD) was demonstrated in study findings presented at the Psych Congress 2020, held virtually from September 10 to 13, 2020.

Evaluation of the convergent validity of the Cognition Kit DSST (Digit Symbol Substitution Test) mobile app in patients with MDD compared with the traditional paper Pearson WAIS IV DSST served as the primary objective of the study. Researchers also assessed patient satisfaction with the smartphone app.

A total of 30 adults (40% men) aged 18 to 65 years (mean 42, SD=13) who were experiencing a moderate to severe major depressive episode as indicated by a score ≥20 on the Montgomery-Asberg Depression Rating Scale were included in the prospective, longitudinal validation study ( Identifier: NCT03999567).

Participants completed a paper DSST and the mobile app DSST at both the initial visit and a second visit scheduled the following week. At the second visit, patients completed a 10-item app satisfaction questionnaire that was scored using a 5-point Likert satisfaction scale. Convergent validity of the mobile app and the DSST was calculated using Pearson correlates.

Positive correlations were found between the DSST score and the mobile app score at both visits (r = .24, P =.207). The researchers also found significant positive correlations between scores on the DSST from the first visit to the second (r = .92, P <.001) and between scores on the mobile app from visit 1 and visit 2 (r = .75, P <.001). Overall, 87% of the respondents indicated that the mobile app was easy to use, and 57% preferred the mobile app to the paper version. All 30 patients agreed that the instructions for the Cognition Kit DSST app were understandable.

Limitations of the study include the small study population and recruitment from a single center. The researchers also noted that the Cognition Kit DSST was validated against only 1 standardized measure and “may not provide adequate conceptual coverage” of all subdomains involved in neurocognition.

“The ubiquity of smartphones provides the opportunity for app-based neurocognitive assessments that are free of charge, and also easy and brief to administer,” the investigators wrote. They believe their study results support the potential of the Cognition Kit DSST mobile app as “a valid and accessible alternative to the paper DSST for measuring cognitive functioning in adults with MDD.”

Disclosure: This clinical trial was supported by Takeda Pharmaceuticals USA, Inc. Several study authors declared affiliations with the pharmaceutical industry. Please refer to the study poster and abstract for a full listing of author disclosures.

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McCue M, Lipsitz O, Subramaniapillai M, et al. Validation of a mobile application version of the cognition kit digit symbol substitution test in patients with major depressive disorder. Presented at: Psych Congress 2020 Virtual Experience; September 10-13, 2020. Poster 213.