JMIR Publications

ABSTRACT

Background:

Background:

Understanding the mechanisms of change in internet-based interventions is crucial for enhancing their effectiveness, improving adherence, and ultimately achieving better treatment outcomes.

Objective:

Objective:

This is a pilot feasibility and mechanisms-focused randomized controlled trial (RCT) investigating the relative contributions of knowledge and acceptance as mechanisms of change in internet-delivered Cognitive Behavioral Therapy (iCBT) and Acceptance and Commitment Therapy (iACT) for insomnia in primary care.

Methods:

Methods:

An 8-module online insomnia program was adapted into distinct iCBT and iACT formats, and a novel sleep knowledge test was developed to measure conceptual understanding, aiming to clarify the complementary roles of knowledge and acceptance in effective digital mental health care. This study explores how sleep knowledge and acceptance influence treatment adherence, outcome process and feasibility using surveys pre-, mid- and posttreatment. Since the data was non-parametric, a split-plot ANOVA was performed, both on all participants using last observation carried forward (LOCF) and the participants that completed all measurements, using listwise deletion. Furthermore, a Friedman-test for repeated within-group measures and Kruskal-Wallis test for between-group comparisons were conducted.

Results:

Results:

A total of 18 adults with insomnia were randomized into 2 groups with 9 participants in each. While both interventions were well-received, no significant differences in clinical outcomes were found. Effects on sleep problems, comorbid symptoms and psychological mechanisms were modest and inconsistent, although the iACT-group exhibited higher treatment adherence. Participant feedback emphasized the value of flexible, blended delivery formats and the need to tailor treatment components to individual preferences.

Conclusions:

Conclusions:

Despite limitations such as small sample size and a large amount of missing data, these findings support the potential of digital interventions to enhance access to insomnia care and tailor it to the patient’s needs. The authors underscore the need for larger, more definitive trials exploring knowledge and acceptance as active mechanisms, as well as micro-interventions and personalized treatment approaches. Clinical Trial: This pilot study is approved by the Regional Ethics Committee in Gothenburg, Sweden (Dnr: 767-18). The participant recruitment took place withing the regular patient flow and no funding was received, but it constituted a part of a mandatory internship performed after the psychology degree and before receiving a psychologist license (PTP).