Evidence map›Paper›PMID 42241028›Full record

Trial reportJournal of sleep research2026

Lights On or Off? The Efficacy of Light Therapy as Add-On to Cognitive Behavioural Therapy for Insomnia-A Pilot Study.

Sarah R Schmid, Christine Blume, Johanna Ell, Nikolas Konzen, Matthias Apweiler, Bernd Feige, Bernd L Fiebich, Julian E Schiel, Katharina Domschke, Kai Spiegelhalder

Abstract readRandomized Controlled Trial
In one paragraph

Trial report in Journal of sleep research, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors.

Sarah R SchmidDepartment of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
Christine BlumeCentre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland.
Johanna EllDepartment of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.ORCID https://orcid.org/0000-0002-4035-3308
Nikolas KonzenDepartment of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
Matthias ApweilerCentre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland.ORCID https://orcid.org/0009-0009-1766-3322
Bernd FeigeDepartment of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.ORCID https://orcid.org/0000-0002-9436-1258
Bernd L FiebichNeuroimmunology and Neurochemistry Research Group, Department of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
Julian E SchielDepartment of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
Katharina DomschkeDepartment of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
Kai SpiegelhalderDepartment of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.ORCID https://orcid.org/0000-0002-4133-3464

Funding

EUCOR
6 · The paper itself

Abstract

Cognitive behavioural therapy for insomnia (CBT-I) is recommended as first-line treatment for insomnia disorder. However, around 25% of the patients do not respond to the treatment, and only 40% achieve full remission. The current study investigates the therapeutic potential of light therapy as an add-on to CBT-I. Insomnia severity and questionnaire-related secondary outcomes were assessed at baseline, post-treatment and follow-up. Sleep diary-related variables and the cortisol awakening response were assessed at pre- and post-treatment. Linear mixed models were calculated for each outcome variable. The study included 42 patients with insomnia disorder. Reduction in insomnia severity did not significantly differ between groups from baseline to post-treatment (β = 0.35, SE = 1.31, p = 0.792). Regarding exploratory secondary outcomes, daytime sleepiness was significantly more reduced from baseline to follow-up in the CBT-I + light therapy group than in the CBT-I + placebo light group (β = -1.05, SE = 0.43, p = 0.020). There was no significant condition × time point interaction effect for any of the other secondary outcomes. The findings show no significant add-on effect of light therapy on insomnia severity. However, light therapy had a significant effect on daytime sleepiness that became evident only at the follow-up. Given that daytime functioning is of high clinical relevance for patients with insomnia disorder, daytime sleepiness should be further evaluated as treatment target and may be addressed with light therapy.

trial registrationClinicalTrials.gov identifier: DRKS00029640.

Indexed as

Cognitive Behavioral TherapyPhototherapySleep Initiation and Maintenance DisordersAdultCombined Modality TherapyCortisol Awakening ResponseFemaleHumansMaleMiddle AgedPilot ProjectsSeverity of Illness IndexTreatment OutcomeCBT‐Iinsomnialight therapysleepiness

Identifiers

PMID42241028
PMCPMC13619079

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.