Validation of the THINC-it Tool for Cognitive Dysfunction in Major Depressive Disorder
Condition: Major Depressive Disorder
MeSH terms: Depressive Disorder; Depression; Depressive Disorder, Major; Cognitive Dysfunction
Study type: Observational

Summary: 
      Cognitive dysfunction is a highly persistent, pervasive and progressive abnormality in young
      adults (i.e., 18-65 years) with MDD. It has also been shown that among adults with MDD who
      are gainfully employed, measures of cognition are a greater determinant of overall workplace
      performance than is total depression symptom severity. Several lines of evidence indicate
      that cognitive deficits that persist between episodes of depression are critical determinants
      of functional recovery in the workplace. The functional implications associated with
      cognitive impairment provide the impetus for systematic evaluation, measurement and
      assessment of the domains of cognition expected to be impaired in this patient population.

      To date, no measurement tool has been sufficiently validated and/or determined to be
      sensitive to the cognitive deficits in younger adults with MDD. Major limitations of
      available comprehensive psychometric tools include relative lack of availability, cost, lack
      of access to most healthcare providers, and above all else, the lengthy time to administer.
      Moreover, the need for a psychometrist to interpret the results adds to the complexity and
      the costliness of such an endeavor.

      It is imperative that any tool recommended for clinical utility be aligned with the busy
      nature of a high-volume clinical practice. The ideal gold standard tool for assessing the
      presence of cognitive dysfunction in MDD in the clinical environment should include, but not
      be limited to, features such as good conceptual coverage of cognitive domains affected in
      MDD, good sensitivity and reliability, and it should be relatively uninfluenced by culture
      effects and practice effects. The tool would also need to be brief, easy to administer and
      interpret, and complement busy clinical practice.

      This study is designed to validate a brief user-friendly tool capable of detecting deficit in
      cognitive performance among adults with MDD. Data will be gathered with the aim to determine
      whether the proposed tool identifies cognitive deficits in adults with MDD and differentiates
      the clinical MDD population from healthy controls.

      It is anticipated that the THINC-it tool will be free of charge and downloadable from the
      THINC-it website for use in the primary care and specialty setting. The THINC-it tool will be
      accessible via computers/tablets, will take 20 minutes to self-administer in a clinical
      setting, and the performance results will be immediately available.
    


Intervention name(s): THINC-it Tool; Pencil-and-paper Cognitive Tests
Intervention type(s): Other; Other
Intervention description(s): Digitalized cognitive test application administering the following cognitive test components:
Digit Symbol Substitution Test (DSST)
Choice Reaction Time (CRT)
One-back working memory tool
Trail Making Test B (TMT-B)
Perceived Deficits Questionnaire-5 Depression (PDQ-5-D); Pencil-and-paper versions of the following cognitive tests:
Digit Symbol Substitution Test (DSST)
Trail Making Test B (TMT-B)
Perceived Deficits Questionnaire-5 Depression (PDQ-5-D)
Variant of Choice Reaction Time (CRT)
Variant of the One-back working memory tool
Observational model: Case-Control
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        All patients will be enrolled at a single site, located in Toronto, Ontario, Canada. The
        total planned number of participants is:

          -  100 individuals with DSM-5-defined MDD, aged 18-65

          -  100 healthy controls matched on age, sex and years of education An equal allocation of
             subjects with MDD between the ages of 18-44 and 45-65 will be enrolled.

        Healthy controls will be consecutively recruited via media announcements.