Effectiveness of the DMHI and OPS Platform in Improving Participant QOL: a Randomised Controlled Trial.

Inclusion Criteria: * Aged ≥18 years; * No current clinical diagnosis of a mental health disorder; * No mental-health treatment or psychotropic medication initiated within the past 3 months; * Able to access the internet and provide informed consent. Exclusion Criteria: * Current engagement with a mental health professional or therapy; * Inability to access the DMHI and OPS platform, or inability to provide informed consent; * PHQ-9 score ≥15 or GAD-7 score ≥15 at baseline (these participants will be referred to specialist services and excluded from further study participation) Confirmation of eligibility to participate. To comply with local regulations and ensure participant safety, a qualified and appropriately licensed specialist, affiliated with the institution will participate in screening of the participants recruitment results and carrying out decisions on whether to include or exclude the participant from the study based on degree of severity in the underlying psychological or psychiatric condition. The decision to exclude participants will be made based on safety considerations, need for emergency psychiatric help, compliance assumption and perceived efficacy. Withdrawal. Participation is voluntary. All enrolled participants are free to withdraw from the study at any time with or without notice to study personnel. Risk to self and/or others. During enrollment and study course, participants will be screened for severity of symptoms. If our participating specialist identifies a risk to self or others, appropriate actions will be taken to contact the authorities and local law representatives according to European and Local Law. Sample size estimates. For two groups and a dichotomous endpoint (improvement or no improvement) and an anticipated incidence of 45% in the intervention group and 75% in the control group, at a 95% confidence level and 5% margin of error, power of 80% and enrolment ratio of 1, a sample size of 82 participants was chosen for this RCT (41 in intervention group, 41 in control group).