@brennankahan.bsky.social
Principal Research Fellow in Medical Statistics at MRC Clinical Trials Unit at UCL. Clinical trials, estimands, estimation. https://scholar.google.co.uk/citations?user=Lf0jsXAAAAAJ&hl=en&oi=sra
The epistemological trap from the real-world evidence concept. - Journal of Clinical Epidemiology www.jclinepi.com/article/S089...
*Using Simulation Studies to Evaluate Statistical Methods* by @matteoq21.bsky.social & Tra My Pham (@mrcctu.bsky.social).
🗓️ 19 – 20 & 26 – 27 November 2026
🏢 Online
🌐 t1p.de/simulation_s...
As a known HR hater, it brings me no joy to post this but I do think some papers are a bit sloppy with their criticisms of the HR (as highlighted by this nice paper)
Some say the overall HR is not causal. But I don't think this is the case for reasons provided here
"An online sample size calculator for designing partially clustered trials" (@klange-au.bsky.social et al) has now been published in Clinical Trials!
doi.org/10.1177/1740...
This free and user-friendly online calculator makes it easier to ensure a trial is appropriately powered ✅
New post on a topic you might have struggled with if you do simulation studies. For a given data-generating mechanism, you might wonder “What is the true value of my estimand?”
This post describes four ways to learn it.
tpmorris.substack.com/p/learning-t...
New Year, New Job? 📆
If you'd like to contribute to the design, conduct & analysis of research projects (and more!), we are looking for a Medical Statistician to join our team!
Apply by 2nd Feb, 12 noon.
Find out more, and see all of OCTRU's vacancies here: www.ndorms.ox.ac.uk/octru/about-...
As an editor I often see authors fall into a trap of stressing some fancy statistical technique for estimating causal effects. Often neglected are the necessary assumptions to map the data to the estimand. @pausalz.bsky.social and I wrote about it here www.bmj.com/content/391/...
#EpiSky
New paper in @jclinepi.bsky.social: **Estimands: what they are and why we should use them**
We provide simple explanations of:
-estimands and intercurrent events
-how these relate to familliar concepts like ITT
-how to write estimands for protocols
-and more
www.jclinepi.com/article/S089...
Just a reminder about the new all-island Irish Reproducibility Network. There are already lots of great people involved. You can sign up and find local site leads with the link, and if you are based in Cork feel free to reach out to me directly.
irishrn.org
NEW PAPER: "Reporting guidelines for studies involving generative artificial intelligence applications: what do I use, and when?"
--> www.nature.com/articles/s41...
#HealthTech #ClinicalAI #MachineLearning #MedAI #AIinMedicine #TransparentAI #HealthInnovation #GenAI
The term #estimand is now part of the technical language of trials - but it remains a concept that many find hard to understand. Recent work has aimed to make the term more accessible to researchers, patients & public 1/8
#MethodologyMonday #127
NEW paper "Clinical prediction models using machine learning in oncology: challenges and recommendations"
--> tinyurl.com/2h2mcy5h
#machinelearning #prediction #statssky #MLsky #methodsmatter
📢 New publication in #Trials led by @suziecro.bsky.social with the HEALTHY STATS public involvement group: Supporting public involvement in defining estimands: a practical tool accessibly explaining the five key attributes of an estimand trialsjournal.biomedcentral.com/articles/10....
We're excited to share our latest work on estimands in clinical trials!
📄 Estimating treatment effects in trials with outcome data truncated by death: A case study on aligning estimators with estimands.
🔗 Read the full paper: journals.sagepub.com/doi/10.1177/...
Want to come work on SNAP, BALANCE+, and STRAP? And change how we treat and manage bloodstream infections? See below. #IDSky
📢 Interested in a PhD in clinical trials methodology? The Trials Methodology Research Partnership are advertising projects for PhDs starting Oct 2026, in statistics, health economics, epidemiology, social science, and more, hosted at one of 12 UK partner institutions.
mrctmrpdtp.com/current-oppo...
📢 As one of the next round of TRMP PhD students (below) you could join me, Clare Robinson, @averoniki.bsky.social and @marionkcampbell.bsky.social to work on developing a typology of research outputs in trials methodology, based at @wiphcem.bsky.social. Details here: www.findaphd.com/phds/project...
🎓 Thinking about a PhD in clinical trial #methodology?
We have two funded PhD opportunities for students passionate about trial design and statistical methods:
• One in estimands
• One in non-inferiority trials
🔗 More info and how to apply here: buff.ly/lCpqcF6
@mrcnihrtmrp.bsky.social
New PhD position available at @mrcctu.bsky.social to develop guidance on balancing statistical and clinical considerations when choosing an estimand in RCTs.
www.findaphd.com/phds/project...
The recording of this webinar is now available on the @nihr-rss.bsky.social YouTube channel: www.youtube.com/watch?v=4cNz...
Lots of feedback and engagement after this session. Some gentle push-back still: "But what if there's even just a *perception* from sites that a stepped wedge is preferable?" 🧵
A scoping review identified additional considerations for defining estimands in cluster randomised trials - Journal of Clinical Epidemiology www.jclinepi.com/article/S089...
Introductory online INSPECT-SR workshop. November 6th, 12-2pm UK-time. Free, places limited. BOOK: www.trybooking.com/uk/events/la...
The number needed to treat: It is time to bow out gracefully - Journal of Clinical Epidemiology www.jclinepi.com/article/S089...
There has been a lot of debate recently about the promise of real world data - the routine (observational) data collected on patients eg treatments received, clinical outcomes etc – for estimating treatment effects. But can they deliver? 1/9
#MethodologyMonday #123
Improving the design of staggered implementation cluster randomised trials qualitysafety.bmj.com/content/earl...
We often now hear the term “Bayesian borrowing” in trials. But what is Bayesian borrowing and what are the pros and cons around its use? 1/6
#MethodologyMonday #122
NEW PAPER in @bmj.com "Dealing with continuous variables and modelling non-linear associations in healthcare data: practical guide"
--> www.bmj.com/content/390/...
#methodologymatters #StatsSky #EpiSky
If outcome = "no. of antibiotic prescriptions" and more people in one arm get LT antibiotics (which presumably precludes further prescriptions?), this does seem like a challenge.
Could of course be good reasons for it - does highlight importance of estimands (along with justifications for choice)!
Think they've used a treatment policy strategy (ie were interested in the effect of Hiprex vs placebo whether or not people started on suppressive antibiotics later).
I don't know enough about the area to say if this is sensible, but if suppressive antibiotics are part of usual care, it may be?