An observational study in Major Depressive Disorder, Mood Disorders and Bipolar Disorder (BD), sponsored by Karolinska Institutet. Not yet recruiting. Open to participants aged 18 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-02-23.
Sponsored by Karolinska Institutet · Observational
This trial has two studies. In study 1, the investigators will explore the relationships between three psychobiological factors (sleep patterns, motor activity, and decision-making ability). The investigators aim to investigate how these factors interact in BD patients. This understanding will facilitate the distinction of BD patients from patients with recurrent depressive disorder (MDD) and healthy controls.
In study 2, the investigators will continue following patients with bipolar disorder and use the interplay between the three psychobiological factors to develop early markers of full-blown affective episodes.
3,041 studies on the registry are indexed under Depressive Disorder, Major; 588 are open to participants now.
This study's planned enrollment of 600 is above the median of 131 across 400 observational studies indexed under Depressive Disorder, Major.
Browse Depressive Disorder, Major studies →Karolinska Institutet is the lead sponsor of 1,148 studies on the registry; 276 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
For all participants:
For patients with bipolar disorder
For patients with recurrent depression
Exclusion Criteria:
Common to all participants:
For adults without psychiatric illness:
For patients with bipolar disorder and patients with recurrent depression:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
150 Individuals with a diagnosis of bipolar disorder will participate in studies 1 and 2
250 patients from three affective clinics in the Stockholm Region (Northwest Psychiatry, North Stockholm Psychiatry, Southwest Psychiatry) who have been referred for assessment for bipolar disorder. Based on clinical experience, approximately 20% (approximately 50 patients) will ultimately be diagnosed with bipolar disorder, while the remaining 200 patients will retain their diagnosis of recurrent depression and be included as a comparison group in study 1 only. The 50 patients newly diagnosed with bipolar disorder will be included in studies 1 and 2.
200 Individuals with no major psychiatric disorder will participate in study 1 only.
Sleep onset
Smartwatch measure of sleep onset.
Time frame: 12 weeks for study 1; 1 year for study 2
Motor activity
Smartwatch data on number of steps each half time of the day
Time frame: 12 weeks for study 1; 1 year for study 2
Learning rate
We will administer a reward learning task and use computational modeling to extract a learning rate.
Time frame: 12 weeks for study 1; 1 year for study 2
Reward sensitivity
We will administer a valence go/no go task and use computational model to extract reward sensitivity.
Time frame: 12 weeks for study 1; 1 year for study 2
Motivational bias
We will administer a valence go/no go task and use computational model to extract a motivational bias.
Time frame: 12 weeks for study 1; 1 year for study 2
Effort discounting
We will administer an effort discounting task and use computational modeling to extract an effort discounting parameter.
Time frame: 12 weeks for study 1; 1 year for study 2
Foraging exit threshold
We will administer foraging task and calculate a foraging exit threshold.
Time frame: 12 weeks for study 1; 1 year for study 2
Sleep duration
Smartwatch measure of sleep duration.
Time frame: 12 weeks for study 1; 1 year for study 2
Sleep quality
Smartwatch measure of sleep quality.
Time frame: 12 weeks for study 1; 1 year for study 2
Questionnaire
Karolinska Sleep Questionnaire (KSQ)
Time frame: 12 weeks for study 1; 1 year for study 2
Questionnaire
Reduced Morningness-Eveningness Questionnaire
Time frame: 12 weeks for study 1; 1 year for study 2
Questionnaire
Center for Epidemiologic Studies Depression Scale Revised (CESD-R)
Time frame: 12 weeks for study 1; 1 year for study 2
Questionnaires
Altman Self-Rating Mania Scale (ASRM)
Time frame: 12 weeks for study 1; 1 year for study 2
Questionnaire
Munich Chronotype Questionnaire (MCTQ)
Time frame: 12 weeks for study 1; 1 year for study 2
Questionnaire
Insomnia Severity
Time frame: 12 weeks for study 1; 1 year for study 2
Questionnaire
Patient Health Questionnaire-9 (PHQ-9)
Time frame: 12 weeks for study 1; 1 year for study 2
No study locations are listed for this record.
Plan to share: Undecided
No publications or documents are linked to this record.
Start is estimated for Apr 2026; primary completion for Dec 2030, 56 months later.
Of 121 non-industry observational studies under Depressive Disorder, Major, half reached primary completion within 46 months of starting (the median), counting those still running; a quarter within 29 and three quarters within 73. This study's planned 56 months is above that.
Counting every sponsor, half of 150 studies reached it within 38 months; a quarter within 21 and three quarters within 67.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Oct 2025. You cannot join it, but the record below documents what was studied.
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