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Constantin Yves Plessen

@cyplessen.bsky.social

Psychologist & psychometrician exploring researcher degrees of freedom in meta-analyses & psychometrics at University of Graz.

840 Followers  |  1,072 Following  |  144 Posts  |  Joined: 12.10.2023
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Posts by Constantin Yves Plessen (@cyplessen.bsky.social)

🧡 New WP with @kaimiele.bsky.social. We document 2 unsettling patterns in mental health care: 1) despite universal coverage, few individuals with mental illness receive guideline-consistent treatment, and 2) the more severe the illness, the lower the treatment uptake & the longer the wait times. 1/n

05.02.2026 08:35 β€” πŸ‘ 65    πŸ” 28    πŸ’¬ 6    πŸ“Œ 6

Want to feel sad and hopeful at once? WhatΒ΄s needed beyond Open Science?

"All of the ingredients for low quality occurring at some non-negligible rate seem to already be in place"β€”the nicest way I've ever heard someone say a terrible true thing.

What a great pitch for forensic meta-science ✌️

15.01.2026 17:56 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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When psychologists mislead us From Piltdown Man to the Stanford prison experiment, many famous scientific discoveries have been exposed as hoaxes or distortions

"The rewards to 'discovering' a spectacular scientific finding [in psychology] are large; the rewards to debunking frauds or deflating exaggerated claims are small if not non-existent. If these are the rules of the game, we should not be surprised at the way the game is played."

15.01.2026 15:51 β€” πŸ‘ 41    πŸ” 14    πŸ’¬ 1    πŸ“Œ 1
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Innovations to improve outcomes and uptake of psychotherapies for mental disorders: a state‐of‐the‐art review Psychotherapies have been found effective in the treatment of most mental disorders. However, substantial improvements are still much needed, and many innovations of therapies are currently being dev...

Many innovations of psychotherapies are currently examined. See our overview in the last issue of World Psychiatry: (1) Digital interventions (2) Personalized treatments (3) New/ improved therapies (4) Dissemination
With @mathiasharrer.bsky.social @toshi-frkw.bsky.social
doi.org/10.1002/wps....

15.01.2026 13:29 β€” πŸ‘ 7    πŸ” 4    πŸ’¬ 0    πŸ“Œ 1
Open Science Basel Year 6 #4 - Ian Hussey
YouTube video by BAMM Open Science Basel Year 6 #4 - Ian Hussey

πŸ“½οΈ "Taboo topics we can no longer avoid: negligence, tampering, and fraud" / with Ian Hussey @ianhussey.mmmdata.io

youtu.be/sdRRafephyM?...

The event was organised by ReproducibiliTea UniBasel @swissrn.bsky.social

15.01.2026 09:44 β€” πŸ‘ 17    πŸ” 12    πŸ’¬ 0    πŸ“Œ 1
OSF

Depending on assumptions, 77–91% of people needing treatment lack access to insurance-funded psychotherapy.

Preprint: osf.io/preprints/ps...
OSF (data & code): osf.io/z9htq

15.01.2026 09:14 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

We synthesize 35 years of estimates on psychotherapy treatment need (1990–2025), assess their quality, and compare them to current treatment capacity.

Across all scenarios, Austria’s publicly funded psychotherapy system meets far less than estimated need.

15.01.2026 09:14 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

New preprint πŸ“„

How many psychotherapists does Austria need?

This one is special to me beyond the topic: it’s an update of the very first paper I ever wrote, almost a decade ago.

And I’ve always wanted to open a paper with a joke β€” this time I finally did. Let’s see if it survives peer review.

15.01.2026 09:14 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 2    πŸ“Œ 1
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WARN-D machine learning competition is live Β» Eiko Fried If you share one single thing of our team in 2026β€”on social media or per email with your colleaguesβ€”please let it be this machine learning competition. It was half a decade of work to get here, especi...

After 5 years of data collection, our WARN-D machine learning competition to forecast depression onset is now LIVE! We hope many of you will participateβ€”we have incredibly rich data.

If you share a single thing of my lab this year, please make it this competition.

eiko-fried.com/warn-d-machi...

07.01.2026 19:39 β€” πŸ‘ 188    πŸ” 159    πŸ’¬ 5    πŸ“Œ 5

I love that they kept the interviewers’ reaction to the sentence you quoted:

β€œLook at your face,” Mr. Zervas said. β€œYou’re horrified.”
πŸ˜‚

07.01.2026 08:09 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Fifteen of those twenty years were spent writing unsuccessful grant applications.

26.12.2025 10:48 β€” πŸ‘ 132    πŸ” 35    πŸ’¬ 3    πŸ“Œ 0
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Why are we still using the PHQ-9? A Historical Review and Psychometric Evaluation of Measurement Invariance - Psychiatric Quarterly The Patient Health Questionnaire-9 (PHQ-9) is a widely used tool for assessing depressive symptom severity and as a screening tool in the diagnosis of major depression. Designed as both a diagnostic i...

"(...) observed changes in PHQ-9 scores over treatment weeks may, at least partly, reflect shifts in how participants engage with the scale rather than true changes in depressive symptomatology." link.springer.com/article/10.1...

14.12.2025 21:59 β€” πŸ‘ 4    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0

What are some articles, blogposts, essays, etc. that you still think about over a year later?

Here are a few of mine:

19.04.2025 11:44 β€” πŸ‘ 59    πŸ” 12    πŸ’¬ 14    πŸ“Œ 4
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Accessibility and public availability of treatment protocols and manuals for evidence-based psychological interventions for severe mental disorders: A survey of randomized trials Background: Psychological interventions are developed and tested as packages of multiple components. Identifying active ingredients requires access to detailed intervention descriptions, such as from ...

Yes, I am one of those horrible people who submit during the season. New preprint, 1st paper from my #ERCStG DECOMPOSE
www.medrxiv.org/content/10.1...
The goals of DECOMPOSE are break-down psychological interventions into components, integrate these in a taxonomy and evaluate incremental efficacy

30.12.2024 08:29 β€” πŸ‘ 38    πŸ” 14    πŸ’¬ 3    πŸ“Œ 0
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HOW MUCH SCIENCE IS FAKE? Hosted on the Open Science Framework

I am seeing this paper cited everywhere, @sciencenews.bsky.social @naturenews.bsky.social conferences, soon policy papers
osf.io/5rf2m/
First, what is the method of this paper? Systematic review? Scoping review? Overview of reviews? Narrative review? Or none was adequate?

28.12.2024 10:37 β€” πŸ‘ 27    πŸ” 12    πŸ’¬ 5    πŸ“Œ 1

JBI, Cochrane and Campbell Collaboration are partnering to co-facilitate an initiative, Building a Global Evidence Synthesis Community. We are calling for expressions of interest to join us as we seize a once-in-a-generation opportunity for a global step change in #EvidenceSynthesis synthesis. 🧡1/

12.12.2024 08:42 β€” πŸ‘ 27    πŸ” 8    πŸ’¬ 2    πŸ“Œ 1
Post image

This is not a hypothetical question in my case, and I am only slightly embarrassed πŸ˜‚

06.12.2024 08:46 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
Figure 1 from BMJ Mental Health paper, showing AI generated images for different mental disorders.

Figure 1 from BMJ Mental Health paper, showing AI generated images for different mental disorders.

Stigmatising and inaccurate portrayals of mental disorders:

Researchers asked generative AI models to depict different disorders.

Images reflected historical biases & pop-culture references rather than evidence-based clinical representation of these conditions

mentalhealth.bmj.com/content/27/1...

05.12.2024 11:10 β€” πŸ‘ 29    πŸ” 13    πŸ’¬ 1    πŸ“Œ 5

Thank you!

03.12.2024 20:12 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
Constantin Yves Plessen

Starting my job search: I just finished my PhD in Clinical Psychology and am looking for opportunities to make an impact.

I have expertise in meta-analyses, advanced stats, psychometrics, R, and project management.

If you know of a position that might be a great fit, please feel free to reach out.

03.12.2024 09:55 β€” πŸ‘ 16    πŸ” 6    πŸ’¬ 2    πŸ“Œ 0
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REED: Do a DAG Before You Do a Specification Curve Analysis My previous two blogs focused on how to do a specification curve analysis (SCA) using the R package β€œspecr” (here) and the Stata program β€œspeccurve” (here). Both blogs provided line-by-line explana…

Do a DAG Before You Do a Specification Curve Analysis #CausalSky #Stats
replicationnetwork.com/2024/11/18/r... With an example of reducing >1,200 specifications to 6. Computational power should not replace theoretical thinking and model building. 1/

25.11.2024 15:27 β€” πŸ‘ 10    πŸ” 4    πŸ’¬ 1    πŸ“Œ 0

TIL blue zones of longevity are not real:

β€œNewman’s main argument is that a significant proportion of supposed centenarians may simply not exist. His research shows that around 1900, when the U.S. started to issue birth certificates, the number of centenarians aged 110 or older dropped sharply…”

24.11.2024 21:03 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
PubPeer - Practice of neurosurgery on Saturn There are comments on PubPeer for publication: Practice of neurosurgery on Saturn (2024)

2/ They even describe it on Pubpeer: β€œThis symbolic document provides an examination of medical malpractice within the field of neurosurgery, utilizing fictional scenarios that draw inspiration from actual cases frequently encountered in this specialty.”

23.11.2024 11:04 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

1/ Put away your pitchforksβ€”I actually enjoyed the paper. It’s a clever fable set in space, exploring β€œthe various difficulties that impact surgical outcomes.” It creatively contrasts patient-centered, evidence-based medicine with current practices (and future ones on Saturn).

23.11.2024 11:04 β€” πŸ‘ 7    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Ever since a reviewer took the time to feedback my R code, highlighted steps that were hard to follow, and reran my analyses on their computer, I do the same when reviewing.

In general: seeing the supplement as an integral part of the paper and not as an afterthought!

22.11.2024 21:47 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

How to deal with conflicting claims from multiple meta-analyses on the same topic?

Especially regarding: publication bias, state-of-the-art methodsβ€”should we apply all or only some corrections?

And what evidential value do meta-analyses of only high-risk-of-bias studies hold?

22.11.2024 18:14 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Just wanted to let everyone know that the one and only Pim Cuijpers and Toshi Furukawa are now on Bluesky as well! :)

@pimcuijpers.bsky.social
@toshi-frkw.bsky.social

#PsychSciSky #psychiatry #statssky #psychsky

22.11.2024 13:23 β€” πŸ‘ 17    πŸ” 5    πŸ’¬ 1    πŸ“Œ 0

Updated -largely no exhaustive- list : go.bsky.app/R8RNJgc
Please reply to be added.

22.11.2024 07:25 β€” πŸ‘ 82    πŸ” 33    πŸ’¬ 64    πŸ“Œ 2

A largely non exhaustive pack for meta research and open science. Please circulate it ;)

go.bsky.app/R8RNJgc

21.11.2024 21:26 β€” πŸ‘ 17    πŸ” 14    πŸ’¬ 3    πŸ“Œ 0

Spoiler: Incredibly sad and weirdly funny:

β€œThe optimistic point is, in the long arc of things, we’ll self-correct, even if we have no incentive to retract or take responsibility.”

β€œDo you believe that?” I asked.

β€œOn my optimistic days, I believe it.”

β€œIs today an optimistic day?”

β€œNot really.”

20.11.2024 09:21 β€” πŸ‘ 4    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0