Evidence map›Paper›PMID 40615135›Full record

ArticleBMJ open2025

Cognitive deficits in treatment-resistant depression: protocol for a systematic review and meta-analysis.

Eivind Haga Ronold, Daniel Jensen, Anders Lillevik L Thorsen, Rune Raudeberg, Leif Oltedal, Åsa Hammar, Marco Hirnstein, Katie Douglas, Richard Porter, Maximilian Kiebs

Abstract read
In one paragraph

Article in BMJ open, 2025. 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.

Eivind Haga RonoldDepartment of Medical and Biological Psychology, University of Bergen Faculty of Psychology, Bergen, Norway.ORCID http://orcid.org/0000-0002-7081-5147
Daniel JensenBetanien Sykehus, Bergen, Norway.ORCID http://orcid.org/0000-0001-6391-6612
Anders Lillevik L ThorsenDepartment of Medical and Biological Psychology, University of Bergen Faculty of Psychology, Bergen, Norway.ORCID http://orcid.org/0000-0003-2836-5223
Rune RaudebergDepartment of Medical and Biological Psychology, University of Bergen Faculty of Psychology, Bergen, Norway.ORCID http://orcid.org/0000-0003-0919-6479
Leif OltedalMohn Medical Imaging and Visualization Centre, Department of Radiology, Department of Radiology, HaukelandUniversity Hospital, Bergen, Norway.
Åsa HammarDepartment of Medical and Biological Psychology, University of Bergen Faculty of Psychology, Bergen, Norway.
Marco HirnsteinDepartment of Medical and Biological Psychology, University of Bergen Faculty of Psychology, Bergen, Norway.ORCID http://orcid.org/0000-0002-6291-0929
Katie DouglasDepartment of Psychological Medicine, University of Otago, Christchurch, New Zealand.ORCID http://orcid.org/0000-0002-5344-2959
Richard PorterDepartment of Psychological Medicine, University of Otago, Christchurch, New Zealand.ORCID http://orcid.org/0000-0002-8695-3966
Maximilian KiebsDept. of Psychiatry and Psychotherapy - School of Medicine and Health Sciences Carl von Ossietzky University of Oldenburg, Oldenburg, Germany m.kiebs@uol.de.ORCID http://orcid.org/0000-0002-4216-2679

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

introductionMajor depressive disorder (MDD) is a major global healthcare challenge. This is, in part, due to the lack of treatment response and chronic course of MDD. Such a course of illness is often termed treatment-resistant depression (TRD) and is seen in over one-third of people with MDD. Reasons for treatment resistance are not well established, nor is the definition of TRD. Duration and severity of depression, however, are associated with TRD and are also associated with cognitive deficits. Thus, TRD could be particularly prone to cognitive deficits and at heightened risk for neuroprogression. While the cognitive profile of MDD has been investigated in several systematic reviews, no systematic review of cognition in TRD exists to date. The present study will fill this gap in the literature. It is expected that TRD will show more severe cognitive deficits than generally reported in MDD and deficits in all cognitive functions are expected. METHODS AND ANALYSIS: A systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines will be performed of the databases Embase, Pubmed/MEDLINE, PsychINFO and Cochrane including peer-reviewed studies on humans using standardised cognitive tests. Pilot searching was performed in January 2025 and the full search will be commenced in June 2025, with additional searches following completion. Where sufficient data are reported, a meta-analysis comparing deficits in TRD with MDD and healthy control participants will be performed; alternatively, effects based on norms will be calculated. Meta-regression, subgroup and sensitivity analyses will be conducted to explore moderators that are sufficiently reported in the literature. The quality of studies will be assessed by the Newcastle-Ottawa Scale. ETHICS AND DISSEMINATION: Ethical approval is not necessary to perform the study, and results will be presented at a suitable conference and published in a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42024538898.

Indexed as

Cognitive DysfunctionDepressive Disorder, Treatment-ResistantMajor Depressive DisorderHumansMeta-Analysis as TopicResearch DesignSystematic Reviews as TopicCognitionDepression & mood disordersMeta-AnalysisSystematic Review

Identifiers

PMID40615135
PMCPMC12226934

What OpenQuestion holds

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Registered trials

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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.