INTRODUCTION Behavioral activation (BA) is effective for the treatment of depression. The Health Action Process Approach (HAPA), which is derived from health psychology, can provide a motivational-volitional framework of BA. OBJECTIVE This study investigated the efficacy of a HAPA-based internet-delivered BA intervention (iBA; called InterAKTIV) in individuals with depression, also assessing HAPA-based motivational and volitional outcomes. METHODS In a two-arm randomized controlled efficacy trial with a parallel design, 128 participants with a major depressive episode were randomly allocated to the intervention group (IG; TAU + immediate access to iBA) or control group (CG; TAU + access to iBA after follow-up). The primary outcome of clinician-rated depressive symptoms and secondary outcomes were assessed at baseline (T1), 8 weeks (T2), 6-month after randomization (T3). Data were analyzed on an intention-to-treat basis. RESULTS Linear mixed model analyses revealed a significant group*time interaction effect on clinician-rated depressive symptoms favoring the IG (F2, 156.0 = 7.40; p < 0.001, d = 0.79 at T2, d = 0.25 at T3). The IG was also superior regarding self-rated depressive symptoms, BA, most motivational, and all volitional outcomes. CONCLUSION This study shows that HAPA-based iBA can significantly improve clinician-rated depressive symptoms, as well as outcomes used in the HAPA model in people with depression. Building on these efficacy results, in the next step, the relationship between BA interventions and activity levels should be investigated, taking into account motivation and volition as potential mediators.

中文翻译：

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基于网络的行为激活干预对抑郁症状、激活、动机和意志的影响：随机对照试验的结果。

简介 行为激活（BA）对于治疗抑郁症是有效的。源自健康心理学的健康行动过程方法（HAPA）可以提供BA的动机-意志框架。目的 本研究调查了基于 HAPA 的互联网提供的 BA 干预（iBA；称为 InterAKTIV）对抑郁症患者的疗效，并评估了基于 HAPA 的动机和意志结果。方法 在一项采用平行设计的双臂随机对照疗效试验中，128 名患有重度抑郁发作的参与者被随机分配到干预组（IG；TAU + 立即使用 iBA）或对照组（CG；TAU + 立即使用 iBA）后续）。临床医生评定的抑郁症状的主要结局和次要结局在基线（T1）、8周（T2）、随机分组后6个月（T3）进行评估。数据是在意向治疗的基础上进行分析的。结果线性混合模型分析显示，临床医生评定的抑郁症状存在显着的组*时间交互效应，有利于 IG（F2，156.0 = 7.40；p < 0.001，T2 时 d = 0.79，T3 时 d = 0.25）。IG 在自评抑郁症状、BA、大多数动机和所有意志结果方面也表现出色。结论 这项研究表明，基于 HAPA 的 iBA 可以显着改善临床医生评价的抑郁症状，以及抑郁症患者 HAPA 模型中使用的结果。基于这些功效结果，下一步应研究 BA 干预措施与活动水平之间的关系，同时考虑动机和意志作为潜在的中介因素。