Development and Preliminary Testing of a Non-regulated Digital Service That Supports Cognitive Behavioral Therapy for Depressive Symptoms Under Clinical Supervision

Drop-Out Rates

时间窗: assessed at end-of-treatment (week 8)

To determine feasibility, we will report rates of and reasons for participant dropout from the trial.

Change in Patient Satisfaction (as Measured by the CSQ-8)

时间窗: Measured at midpoint (week 4) and end-of-treatment (week 8)

The Client Satisfaction Questionnaire (CSQ) is an 8-item self-report questionnaire which assesses the satisfaction with clinical services received. Each item uses a 4-point Likert scale. Items are summed for a total score ranging from 8 to 32, with higher scores indicating greater satisfaction.

Change in Treatment Credibility (as Measured by the CEQ)

时间窗: Change in credibility from baseline (week 0) to midpoint (week 4)

The Credibility/Expectancy Questionnaire (CEQ) is a 6-item, self-report questionnaire. Items 1-3 assess clients' impressions of the treatment credibility; they are scored on Likert scales ranging from 1 to 9 (e.g., from 1='not at all' to 9='very much'). Items are summed for a total score that can range from 3 to 27, where higher scores mean greater treatment credibility.

Change in Outcome Expectancy (as Measured by the CEQ)

时间窗: Measured at baseline (week 0) and midpoint (week 4)

The Credibility/Expectancy Questionnaire (CEQ) is a 6-item, self-report questionnaire. Items 4-6 are used to assess clients' outcome expectancy. Item 5 is scored on a Likert scale ranging from 1 to 9 (where 1='not at all' to 9='very much'). Items 4 and 6 are scored on a scale from 0% to 100% (in 10-point increments); their scores are then converted linearly on a Likert scale from 1 to 9. Items are summed together for a total outcome expectancy score that can range from 3 to 27, where higher scores mean a higher outcome expectancy.

App Rating (as Measured by the uMARS)

时间窗: Measured at endpoint (week 8)

The Mobile Application Rating Scale user version (uMARS) is a self-report form with 26 items that assess participant's evaluations of various app features. Dimensions of this measure include engagement (5 items), functionality (4 items), aesthetics (3 items), information quality (4 items); other items about app subjectivity quality (4 items) and perceived impact (6 items) are also available but do not contribute to the overall score (and are not reported here). Items are rated on differently worded 5-point Likert scales ranging from 1 (Inadequate) to 5 (Excellent). An overall app rating score can be calculated as the mean score of the first four subscales (engagement, functionality, aesthetics, and information quality; range of 1-5), where higher scores indicate higher overall perceived app quality.

Change in Treatment Utilization

时间窗: Measured at midpoint (week 4) and end-of-treatment (week 8)

Treatment utilization was assessed with a single question: "On average, how much time (in minutes) do you spend using the app or practicing skills from the app in total, per week?" Answers were collected as number of minutes in integer format, where more time spent on and off the app was interpreted as greater treatment utilization.