Feasibility Randomized Controlled Trial Using a 'Leapfrog' Design: Optimizing an Internet-delivered Cognitive Training Intervention to Reduce Anhedonia
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 188
- 试验地点
- 1
- 主要终点
- Dimensional Anhedonia Rating Scale (DARS)
研究概览
简要总结
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.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Single (Participant)
盲法说明
Participants are not blind as to whether they are receiving an intervention or monitoring only, but otherwise are blind to the status of which intervention they are receiving, i.e. 'original' version of the imagery CBM or an attempted improvement. Researchers are not blind to participant allocations, but the study is planned to be mostly automated, reducing opportunities to influence participants. Researchers will monitor performance of the arms as data accumulates, via the sequential analyses, and will therefore not be blind to outcomes as the trial progresses.
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •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
排除标准
- •No exclusion criteria set
研究组 & 干预措施
Monitoring
Participants complete weekly questionnaires (QIDS-SR, PMH, GAD-7) on a weekly basis but receive no intervention.
Standard imagery cognitive bias modification
Participants are scheduled to complete a first introductory session then 12 further training sessions of a 'standard' imagery cognitive bias modification (CBM) intervention derived from that implemented in previous studies.
干预措施: Imagery cognitive bias modification (Behavioral)
Standard imagery cognitive bias modification plus additional rationale and transfer instructions
Participants are scheduled to complete a first introductory session then 12 further training sessions of a 'standard' imagery cognitive bias modification (CBM) intervention, but in addition are first presented with a more extended rationale for completing the training, and during each training session are provided with instructions to practice retrieval and rehearsal of the training contents in between sessions.
干预措施: Imagery cognitive bias modification (Behavioral)
Standard imagery cognitive bias modification with frequent brief sessions
Participants are scheduled to complete a first introductory session then 40 brief (~5 min) sessions of a 'standard' imagery cognitive bias modification (CBM) intervention, with 2 per day five days per week for each of the four training weeks. In addition, as with the arm "Standard imagery cognitive bias modification plus additional rationale and transfer instructions", participants are first presented with a more extended rationale for completing the training, and during many of the training sessions are provided with instructions to practice retrieval and rehearsal of the training contents in between sessions. This arm was added into the ongoing trial on 30.05.21.
干预措施: Imagery cognitive bias modification (Behavioral)
Standard imagery cognitive bias modification with a less intensive schedule
Participants are scheduled to complete a first introductory session then 11 further sessions of a 'standard' imagery cognitive bias modification (CBM) intervention, with 3 sessions scheduled for each of the four training weeks. Sessions have fewer training scenarios than the "Standard imagery cognitive bias modification" condition and more varied task instructions. In addition, as with the arm "Standard imagery cognitive bias modification plus additional rationale and transfer instructions", participants are first presented with a more extended rationale for completing the training, and during many of the training sessions are provided with instructions to practice retrieval and rehearsal of the training contents in between sessions. This arm was added into the ongoing trial on 09.06.21.
干预措施: Imagery cognitive bias modification (Behavioral)
结局指标
主要结局
Dimensional Anhedonia Rating Scale (DARS)
时间窗: 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).
次要结局
- GAD-7(Baseline, 1 week post-baseline, 2 weeks post-baseline, 3 weeks post-baseline, post-intervention (4 weeks post-baseline))
- 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))
- Positive Mental Health Scale (PMH)(Baseline, 1 week post-baseline, 2 weeks post-baseline, 3 weeks post-baseline, post-intervention (4 weeks post-baseline))
- Prospective Imagery Test (PIT)(Baseline and post-intervention (4 weeks post-baseline))
- Ambiguous Scenarios Test for Depression (AST)(Baseline and post-intervention (4 weeks post-baseline))
- Negative Effects Questionnaire - Short Form (NEQ)(Post-intervention (4 weeks post-baseline))
研究者
Simon Blackwell
Postdoctoral Researcher
Ruhr University of Bochum