Feasibility Randomized Controlled Trial Using a 'Leapfrog' Design

Not Applicable

Completed

• Conditions: Depression; Anhedonia

• Registration Number: NCT04791137
• Lead Sponsor: Ruhr University of Bochum

Brief Summary

This study is a small-scale randomized controlled trial (RCT) using a 'Leapfrog' design (Blackwell, Woud, Margraf, \& Schönbrodt, 2019) with the aim of investigating feasibility of this design in the context of an RCT of an internet-delivered intervention. The leapfrog design will be applied to a simple cognitive training intervention, imagery cognitive bias modification (imagery CBM), completed over a four-week training period. The trial will start with the three arms described in the initial registration, but these will be removed and new arms added over the course of the trial on the basis of sequential Bayesian analyses.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2021-03-08
• Study First Submitted QC: 2021-03-08
• Study First Posted: 2021-03-10
• Study Start: 2021-04-09
• Status Verified: 2022-01
• Primary Completion: 2022-01-11
• Study Completion: 2022-01-11
• Last Update Submitted: 2022-01-27
• Last Update Posted: 2022-01-28

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 188

Inclusion Criteria

• Aged 18 or over
• Fluent German
• Willing and able to complete all study procedures (including having a suitable device/ internet access)
• Interested in monitoring their mood over the study time-period (one month)
• Score of ≥ 6 on the Quick Inventory of Depressive Symptomatology, including ≥ 1 on item 13 (General Interest), indicating at least mild levels of depression symptoms and anhedonia

Exclusion Criteria

• No exclusion criteria set

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Dimensional Anhedonia Rating Scale (DARS)	Post-intervention (4 weeks post-baseline).	A 17-item scale measuring anhedonia (Rizvi et al., 2015). The primary analysis is a between-groups comparison of post-intervention scores, controlling for baseline scores, using constrained longitudinal data analysis (cLDA). An approximate Bayes factor is then calculated via the t-statistic for the Time x Group effect with a directional default Cauchy prior (rscale parameter = √2/2).

Secondary Outcome Measures

Name	Time	Method
GAD-7	Baseline, 1 week post-baseline, 2 weeks post-baseline, 3 weeks post-baseline, post-intervention (4 weeks post-baseline)	A brief 7-item measure of generalized anxiety symptoms (Spitzer et al., 2006)
Quick Inventory of Depressive Symptomatology - Self Report (QIDS)	Baseline, 1 week post-baseline, 2 weeks post-baseline, 3 weeks post-baseline, post-intervention (4 weeks post-baseline)	A 15-item version of the QIDS (Rush et al., 2013), excluding the suicidal ideation item, will be used
Positive Mental Health Scale (PMH)	Baseline, 1 week post-baseline, 2 weeks post-baseline, 3 weeks post-baseline, post-intervention (4 weeks post-baseline)	A 9-item questionnaire designed to assess positive mental health (Lukat et al., 2016)
Prospective Imagery Test (PIT)	Baseline and post-intervention (4 weeks post-baseline)	A measure designed to assess vividness of positive and negative future-oriented imagery (Stöber et al., 2000), here administered with as two 10-item parallel versions (each with 5 positive and 5 negative items).
Ambiguous Scenarios Test for Depression (AST)	Baseline and post-intervention (4 weeks post-baseline)	A measure with two 15-item parallel forms designed to assess depression-relevant negative interpretation biases (Rochbacher \& Reinecke, 2014)
Negative Effects Questionnaire - Short Form (NEQ)	Post-intervention (4 weeks post-baseline)	A 20-item questionnaire designed to assess potential negative effects of psychological interventions (Rozental et al., 2019)

Trial Locations

Locations (1)

Ruhr University of Bochum; 🇩🇪 Bochum, Nordrhein-Westfalen, Germany