Effects of an Internet intervention (Deprexis) on severe depression symptoms: Randomized controlled trial

Abstract

Background: Studies have shown that certain Internet interventions can help alleviate depression. However, many such interventions contain personal support elements, making it difficult to ascertain whether the program or the support drives the effects. Studies are needed to investigate whether Internet interventions contribute to symptom reduction even when they are delivered without personal support, and even among severely depressed individuals who often receive other forms of treatment. Objective: This randomized controlled trial aimed to examine the effect of an Internet intervention that was deployed without personal support ("Deprexis") among adults with initially severe depression symptoms. Methods: Adults recruited from a range of sources who had exceeded the threshold for severe depression (PHQ-9 ≥ 15) in a pre-screening assessment and met inclusion criteria were randomized (N = 163) to the intervention (3 months program access; n = 78) or care-as-usual/waitlist control (n = 85). A diagnostic screening interview was administered by telephone at baseline to all participants. Online assessments were administered at baseline, 3 months (post-treatment), and 6 months (follow-up). The main outcome was the Patient Health Questionnaire (PHQ-9) between baseline and post-treatment. Results: Eighty-two percent of randomized participants were reached for the post-treatment assessment. Results for the intention-to-treat (ITT) sample showed significant intervention effects on depression reduction between baseline and post-treatment (linear mixed model [MM], F 1,155.6 = 9.00, p b .01, for the time by condition interaction), with a medium between-group effect size, Cohen's d = 0.57 (95% CI: 0.22-0.92). Group differences in depression severity at follow-up were marginally significant in the ITT sample, t (119) = 1.83, p = 0.07, and smaller than at post-treatment (PHQ-9, d = 0.33, 95% CI: −0.03-0.69). The number needed to treat (NNT) at post-treatment was 5, with 38% of participants in the intervention group achieving response (at least 50% PHQ-9 symptom change, plus post-treatment score b 10), compared to 17% in the control group, p b 0.01. Effects on secondary outcomes, including anxiety, health-related quality of life, and somatic symptoms, were not significant, with the exception of significant effects on anxiety reduction in PP analyses. Early ratings of program Internet Interventions 2 (2015) 48-59 ⁎ Corresponding author atInternet Interventions j o u r n a l h o m e p a g e : w w w . i n v e n t -j o u r n a l . c o m / helpfulness/alliance (after 3 weeks) predicted pre-post depression reduction, controlling for baseline severity and early symptom change. Conclusions: These results replicate and extend previous findings by showing that Deprexis can facilitate symptomatic improvement over 3 months and, perhaps to a lesser degree, up until 6 months among adults with initially severe depression.

A secondary analysis of internet-delivered cognitive-behaviour treatment for adults with severe depressive symptoms (Preprint)

“…Outcomes on secondary measures of the GAD and WSAS significantly decreased from pre to post timepoints, with significant differences and large effect sizes observed.These scores did not significantly differ at follow-up points, implying a maintenance of gains across the sample from post-treatment to 3-month follow-up, similar to what was observed by [21]. The decrease in anxiety scores as a result of iCBT treatment for depression was mirrored in the larger RCT this sample was derived from [27].…”

“…The results demonstrate comparative effect sizes of improvement in severe depressive symptoms to those experienced in a mild to moderately depressed group, supporting the use of iCBT for severe depression [12,21]. Over half of the participants who provided pre and post treatment data experienced reliable improvement by participating in the intervention (n = 21), supporting the potential for iCBT as an effective measure in this population.…”

“…As was the case in this study, implementing a iCBT intervention with support ensures sufficient monitoring and the potential to intervene if necessary with a vulnerable population at greater risk than those with mild and moderate depression [21]. It is relatively unknown whether individuals with severe depression benefit more, or less from support than those in the mild to moderate range, though recent analyses has suggested that there is no difference in how different populations of severity benefit [39].…”

“…Nevertheless, there are some studies that have demonstrated the effectiveness of iCBT in reducing symptoms of severe depression [18][19][20] and other studies have found that improvements were maintained at 6-month follow-up [21]. However, the complexities associated with delivering a successful internet-delivered intervention for this population are naturally more challenging, with some studies suggesting that severely depressed individuals participate less in iCBT [22] and sometimes demonstrate less improvement than the mild to moderately depressed group [23].…”

Improving the Efficacy of Cognitive Training for Digital Mental Health Interventions Through Avatar Customization: Crowdsourced Quasi-Experimental Study (Preprint)

“…There are several examples of Internet-based mental health applications that have demonstrated treatment effects [4,5] in Randomized Control Trials (RCTs) [6][7][8]. However, because these mental health interventions are delivered digitally and often outside of a laboratory or clinical context, success is not only defined by efficacy in research, but also defined by efficacy in practice, which depends on validated implementation models and a focus on external validity -that is, demonstrated success in the context of intended use [4,5,9].…”