A data extraction form will be designed in covidence and used to extract equivalent information from each study. Data extraction forms will be piloted initially on a small number of included studies. Subsequently, each of the included studies will be abstracted by two reviewers, independently, and potential conflicts will be resolved through discussion. Authors of primary publications will be contacted (by email) for data clarifications or missing outcome data, as necessary. We will follow-up twice with each author, and wait 1 month after our initial email before excluding an article we are unclear about from the review. Extracted data will include funding sources, country, setting, author, RCT type (i.e., parallel, crossover), blinding and randomization methods, sample size calculation, inclusion and exclusion criteria, group baseline differences, baseline characteristics, intervention details (i.e., number of weeks, theoretical framework, frequency of sessions, length of sessions, expertise of facilitator, group size, incentives/honoraria), control group type, and outcome measurements. The Cochrane Handbook [
28] and Synthesis Without Meta-Analysis (SWiM) [
29] reporting guidelines will be used to conduct and report data synthesis, respectively. Due to the expected variation in interventions and reporting of outcomes, a meta-analysis will not be performed [
30]. Instead, findings will be synthesized narratively and a summary will be presented in a table that includes setting, design, country, population, sample size, analytic method, relationships between group eHealth counseling or coaching and outcomes of interest, and relevant results. We will conduct a summary of findings for each outcome in which five or more studies are selected for review. For example, if five studies selected for the review examined anxiety as an outcome, we will do a summary of findings for that outcome. We have also planned a summary of findings by gender, and the intensity/duration of the interventions. These results will be presented in the “Summary of findings” tables created using GRADEpro [
31]. The risk of bias will be assessed and reported on by MLV and EH using the Cochrane Risk of Bias tool [
32]. Discrepancies will be resolved in a discussion with CC and RL. The risk of bias domains to be analyzed are (a) random sequence generation, (b) allocation concealment, (c) blinding, (d) incomplete outcome data, and (e) selective reporting and other bias. In psychological interventions, blinding is not possible resulting in a high risk of bias rating of (c), which we will discuss in our findings. Higher quality records will be prioritized when drawing conclusions. The role of sex and gender will be considered as well as possible gender biases at all stages of the review process from article selection and synthesis to knowledge mobilization, e.g., creation of gender-specific guidelines for eHealth therapies. Finally, we will narratively summarize the implications of findings as they may pertain to the documented impacts that COVID-19 has had on substance misuse, mental health, and well-being within adult populations to inform the decisions of governments, communities, and health care organizations responding to the pandemic.