Three online self-help interventions for sleep, stress and worry to prevent depression. A randomized effect study

INTERVENTION: Participants are randomised into: 1. Experimental condition 2. Waitlist control condition (with full access to usual care) Participants in the experimental condition have direct access to the online self‐help intervention of their choice (better sleep, less stress or less worry), whereas participants in the control condition gain access to the intervention of their choice after 3 months. Participants are offered three online self‐help‐interventions aimed at sleep, stress and worry. For the purposes of the study, subjects can only participate in one of the three interventions. The theoretical expectation is that a reduction in sleeping problems, stress or worrying will reduce the risk of developing a depressive disorder. Participants can follow the intervention independently from their homes, on a computer, tablet or iPad. Each intervention consists of information (psycho‐education) and exercises. The method is based on principles from cognitive behavioral therapy, mindfulness and positive psychology. 'Sleep better' (in Dutch: 'Beter slapen') is aimed at people who experience difficulties with sleeping, such as sleeping too often, waking up too early or difficulty falling asleep. Participants learn how to manage factors which negatively influence their sleep, as well as how they can positively influence their sleep as to prevent or reduce insomnia. This intervention consists of 19 exercises divided over 4 themes: ‐ Sleeping habits: 5 exercises to gain insight into sleeping habits ‐ Relaxation: 5 exercises to learn how to relax ‐ Less worrying: 5 exercises to reduce worrying ‐ Thinking differently (about sleep): 5 exerices to learn recognizing unhelpful thoughts and transforming these into helpful thoughts 'Less stress' (in Dutch: 'Minder stress') is aimed at people who experience excessive levels of stress. This intervention CONDITION: Stress, Anxiety, Depression, Mental health ; ; PRIMARY OUTCOME: The primary outcome is:; ; ‐ sleep (Jenkins Sleep Evaluation Questionnaire, time points: baseline, 3 months and 6 months);; ; ‐ stress (Perceived stress scale, time points: baseline, 3 months, 6 months); or; ; ‐ worry (Penn State Worry Questionnaire, time points: baseline, 3 months, 6 months).; ; ; ; What the primary measure is depends on which self‐help intervention the participant participates in. For instance, if a participant participates in the self‐help intervention aimed at reducing sleeping problems, the primary outcome will be sleep, and stress and worry will be secondary outcomes. SECONDARY OUTCOME: ‐ Depression (Inventory of Depressive Symptomatology, time points: baseline, 3 months, 6 months) ; ; ‐ Anxiety (Generalized Anxiety Disorder Scale, time points: baseline, 3 months, 6 months) ; ; ‐ Well‐being (Warwick‐Edinburgh Mental Well‐being Scale, time points: baseline, 3 months, 6 months) ; ; ‐ Cost‐effectiveness (Trimbos/iMTA questionnaire for Costs associated with Psychiatric Illness, shortened version, time points: baseline, 3 months, 6 months). INCLUSION CRITERIA: 1. 18 years and older; 2. experiences problems with sleep, stress or worry (subjective experience); 3. experiences mild to moderate depressive symptoms as determined with the Inventory of Depressive Symptomatology (IDS‐SR, score 14‐38); 4. has access to a computer with a solid Internet connection (the intervention and the questionnaires are offered online); 5. has an e‐mail address; 6. has sufficient computer skills; 7. has sufficient Dutch language skills.