Confirmation Bias Towards Treatments of Depressive Disorders in Social Tagging

How Confidence in Prior Attitudes, Social Tag Popularity, and Source Credibility Shape Confirmation Bias Toward Antidepressants and Psychotherapy in a Representative German Sample: Randomized Controlled Web-Based Study

The study examines whether people primarily want to confirm their prior attitudes in health-related information search, in an online environment using social tags for navigation. Participants were looking for information on the treatment of depression with antidepressants and psychotherapy. They were randomly assigned to two groups with either high or low credibility of the community who provides social tags, and two groups where participants' confidence in prior attitudes was heightened or lowered, and to two groups where either antidepressant tags were more popular or psychotherapy was more popular. The investigators measured attitude change toward the treatments and also navigation behavior.

Study Overview

• Status: Completed
• Conditions: Depression; Depressive Disorder, Major; Depressive Episode; Major Depressive Disorder, Recurrent
• Intervention / Treatment: Other: Social Tag Popularity; Other: Confidence in Prior Attitudes; Other: Source Credibility

Detailed Description

In health-related, Web-based information searches, people should select information in line with expert (vs nonexpert) information, independent of their prior attitudes and consequent confirmation bias.

This study aimed to investigate confirmation bias in mental health-related information searches, particularly (1) if high confidence worsens confirmation bias, (2) if social tags eliminate the influence of prior attitudes, and (3) if people successfully distinguish high and low source credibility.

In total, 520 participants of a representative sample of the German Web-based population were recruited via a panel company. Among them, 48.1% (250/520) participants completed the fully automated study. Participants provided prior attitudes about antidepressants and psychotherapy. The investigators manipulated (1) confidence in prior attitudes when participants searched for blog posts about the treatment of depression, (2) tag popularity -either psychotherapy or antidepressant tags were more popular, and (3) source credibility with banners indicating high or low expertise of the tagging community. The investigators measured tag and blog post selection, and treatment efficacy ratings after navigation.

• Study Type: Interventional
• Enrollment (Actual): 520
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 60 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

Online Population - Internet Browser, Representative Sample of Germans with respect to age and region

Exclusion Criteria:

No Internet Browser

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Health Services Research
• Allocation: Randomized
• Interventional Model: Factorial Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Social Tag Popularity; Popularity of Social Tags (antidepressants more popular vs. psychotherapy more popular)	Other: Social Tag Popularity; The relative size of treatment tags in a tag cloud was either larger for antidepressant treatments or psychotherapy treatments.
Experimental: Confidence in Prior Attitudes; Confidence in prior attitudes (high vs. low: recalling situations in which participants were confident or uncertain about their thoughts)	Other: Confidence in Prior Attitudes; Participants thought back of situations in which they were either confident or doubtful about their own knowledge. This should elicit a mindset where participants are more or less confident about their own prior attitudes.
Experimental: Source Credibility; Credibility of the source (tagging community: experts - many years of professional experience vs. novices - students in the first semester)	Other: Source Credibility; The source credibility of the community that allegedly collected and labelled the blog posts was either high or low in terms of expertise. Either experts (high credibility) or first semester students (low credibility) did allegedly collect blog posts. This was indicated by banners on top of the navigation platform in the internet browser.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Attitudinal Preference Score of Psychotherapy over Antidepressants	The investigators constructed a questionnaire to measure the attitudinal preference of psychotherapy over antidepressant treatments of depressive disorders. On a 7-point likert scale, participants rate the degree of efficacy of antidepressant and psychotherapy treatments, on 8 items (e.g. item 1: "Antidepressants/Psychotherapy are/is effective in treating depression."). An index score for the degree of preference of psychotherapy is calculated by subtracting the average antidepressants score from the average psychotherapy treatment rating score for each participant. To analyse if attitudinal preferences predict the number of clicks on social tags and blog posts, the treatment preference score is entered in a logistic regression as predictor. Ratings are inquired at the beginning of the 1 hour study (prior attitudes), and at the end of the study (attitude change).	Through study completion, an average of 1 hour. Prior to and after information search phase in the study.
Count of clicks on antidepressant and psychotherapy treatment tags	Both, psychotherapy and antidepressant tags can be clicked on, and are counted respectively. An index score will be calculated for each participant subtracting the sum of clicks on antidepressants from the sum of clicks on psychotherapy, to analyse if clicks are associated with the treatment preference measured by prior treatment attitudes.	Through study completion, an average of 1 hour. During the information search phase in the study.
Count of clicks on antidepressant and psychotherapy treatment blog posts	Both, psychotherapy and antidepressant blog posts can be clicked on, and are counted respectively. An index score will be calculated for each participant subtracting the sum of clicks on antidepressants from the sum of clicks on psychotherapy, to analyse if clicks are associated with the treatment preference measured by prior treatment attitudes.	Through study completion, an average of 1 hour. During the information search phase in the study.

Collaborators and Investigators

• Sponsor: Leibniz-Institut für Wissensmedien
• Investigators: Principal Investigator: Stefan Schweiger, Leibniz-Institut für Wissensmedien

Publications and helpful links

General Publications

• Schweiger S, Cress U. How Confidence in Prior Attitudes, Social Tag Popularity, and Source Credibility Shape Confirmation Bias Toward Antidepressants and Psychotherapy in a Representative German Sample: Randomized Controlled Web-Based Study. J Med Internet Res. 2019 Apr 23;21(4):e11081. doi: 10.2196/11081.

Study record dates

Study Major Dates

• Study Start (Actual): November 14, 2014
• Primary Completion (Actual): November 14, 2014
• Study Completion (Actual): November 14, 2014

Study Registration Dates

• First Submitted: March 27, 2019
• First Submitted That Met QC Criteria: April 1, 2019
• First Posted (Actual): April 2, 2019

Study Record Updates

• Last Update Posted (Actual): April 2, 2019
• Last Update Submitted That Met QC Criteria: April 1, 2019
• Last Verified: March 1, 2019

More Information

Terms related to this study

• Keywords: Depression; Mood Disorder; Psychotherapy; Antidepressants; Attitudes; Information Search
• Additional Relevant MeSH Terms: Behavioral Symptoms; Mental Disorders; Pathologic Processes; Mood Disorders; Depression; Depressive Disorder; Disease; Depressive Disorder, Major
• Other Study ID Numbers: AG5-2014-11-Tagging

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Individual level data will be anonymized and appended to the publication at the Journal of Medical Internet research.
• IPD Sharing Time Frame: Data will become available upon publication of the study until May 2019.
• IPD Sharing Access Criteria: The completely anonymized data will be available for researchers and the public who access the published paper at the Journal of Medical Internet research.
• IPD Sharing Supporting Information Type: ANALYTIC_CODE

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No