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Jonathan Bartlett @TheStatsGeek

Biostatistician with interests in missing data, causal inference, clinical trials. Professor in Medical Statistics at @LSHTM

Joined May 2014
  • Tweets 925
  • Following 429
  • Followers 2,945
27 Photos and videos
Jonathan Bartlett retweeted
Triad sou.@triadsou
2 Apr 2025
G-formula with multiple imputation for causal inference with incomplete data. Jonathan W Bartlett, Camila Olarte Parra, Emily Granger, Ruth H Keogh, Erik W van Zwet, Rhian M Daniel. Statistical Methods in Medical Research. journals.sagepub.com/doi/ful…

G-formula with multiple imputation for causal inference with incomplete data - Jonathan W Bartlett,...

G-formula is a popular approach for estimating the effects of time-varying treatments or exposures from longitudinal data. G-formula is typically implemented us...

journals.sagepub.com
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Jonathan Bartlett retweeted
Data & Statistical Science for Health, LSHTM@LSHTM_datastats
3 Dec 2024
Don’t forget to join our seminar with @SofiaSVillar1 who will discuss recent developments in response-adaptive randomization 🗓️ Tuesday 10 December 🕰️ 12:50 (UK time) 📍 Online | LSHTM Details ⬇️ lshtm.ac.uk/newsevents/event…
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Jonathan Bartlett retweeted
Data & Statistical Science for Health, LSHTM@LSHTM_datastats
21 Nov 2024
We’re happy to be welcoming @SofiaSVillar1 for our next seminar to discuss recent developments in response-adaptive randomization 🗓️ Tuesday 10 December 🕰️ 12:50 (UK time) 📍 Online | LSHTM Details ⬇️ lshtm.ac.uk/newsevents/event…
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Jonathan Bartlett retweeted
Michael Schomaker@mf_schomaker
18 Nov 2024
Our paper on applying missingness DAGs to longitudinal trial data has just been published in Biostatistics: academic.oup.com/biostatisti… A challenging but rewarding experience. We give ideas on useful rules of thumbs & how to explore deviations from the assumed missingness process.

Recoverability of causal effects under presence of missing data: a longitudinal case study

Summary. Missing data in multiple variables is a common issue. We investigate the applicability of the framework of graphical models for handling missing d

academic.oup.com
Michael Schomaker@mf_schomaker
6 Mar 2024
Causal inference with missing data? Are missingness DAGs and graphical M(N)AR concepts, as proposed by @Carthica & @yudapearl, readily applicable to complex longitudinal studies? Check out our preprint led by @a_holovchak 👇 arxiv.org/abs/2402.14562
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Does the SE formula for a sample proportion assume equal 'success' probabilities? thestatsgeek.com/2024/11/04/…

Does a Bernoulli/binomial model really assume everyone has the same probability p?

When you estimate a proportion and want to calculate a standard error for the estimate, you would normally do so based on assuming that the number of ‘successes’ in the sample is a draw…

thestatsgeek.com
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Multiple imputation with flexible parametric survival models thestatsgeek.com/2024/10/25/…

Multiple imputation with flexible parametric survival models

Following a recent request from someone, I’ve extended the functionality of my R package smcfcs, which performs multiple imputation of missing covariates, compatible with a user-specified sub…

thestatsgeek.com
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Jonathan Bartlett retweeted
CAUSALab@CAUSALab
15 Oct 2024
The @CAUSALab Methods Series at @karolinskainst is back! @jonathanasterne @BristolUni kicks off Fall 2024 with a virtual talk on COVID-19 vaccine effectiveness & OpenSAFELY. Register to attend 👇 stats.sender.net/forms/e7JD1… #causalinference #targettrial #publichealth #causal
2024-2025 Methods Series speaker lineup

ALT 2024-2025 Methods Series speaker lineup

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Jonathan Bartlett retweeted
Stijn Vansteelandt@SVansteelandt
11 Oct 2024
When selecting a causal estimand, it’s crucial to balance asking the right question with the feasibility of answering it under realistic assumptions. Ignoring this in clinical trials risks chasing shadows. arxiv.org/abs/2409.11162 1/2 #CausalInference #PharmaStats #Estimands
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Jonathan Bartlett retweeted
Bethan Copsey@bethan_copsey
3 Oct 2024
Estimand resources available online as highlighted by @Brennan_Kahan at #ICTMC2024 this morning: osf.io/jw6sn/?utm_source=web…
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Jonathan Bartlett retweeted
Covariate Adjustment ASA BIOP Working Group@CAR_SWG
30 Sep 2024
check out the latest article from ASA BIOP Covariate Adjustment SWG here carswg.github.io/posts/blog_… "Covariate Adjustment for Linear Models: Understanding FDA Advice on Standard Errors"
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24th September - please join us online for Devan Mehrotra's seminar on 'Covariate adjustment using treatment-blinded covariate selection within randomized clinical trials', hosted by @LSHTM_datastats. lshtm.ac.uk/newsevents/event…

​​Covariate adjustment using treatment-blinded covariate selection within

​​When estimating treatment effects in randomized clinical trials, the primary goal of covariate-adjustment is to improve precision (e.g., for linear models) and/or reduce bias (e.g., for non-linear

lshtm.ac.uk
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Jonathan Bartlett retweeted
Covariate Adjustment ASA BIOP Working Group@CAR_SWG
3 Sep 2024
Our next journal club is scheduled on Sep 13 at 11am EST. Speaker: Kelly Van Lancker, Ghent University Zoom link: umich.zoom.us/j/7573650566 Title: Automated, efficient and model-free inference for randomized clinical trials via data-driven covariate adjustment

Join our Cloud HD Video Meeting

Zoom is the leader in modern enterprise cloud communications.

umich.zoom.us
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Come and work with @DrPerpo, Adrian Mander, @RuthHKeogh and I on a 3 year Knowledge Transfer Partnership between @GSK and @LSHTM. More details here: jobs.lshtm.ac.uk/vacancy.asp…

Jobs at LSHTM

jobs.lshtm.ac.uk
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Jonathan Bartlett retweeted
Lu Mao
@LuMaoWisc
30 Jul 2024
Win ratio has been widely used, but so far with little attention to its estimand. I argue for articulating the estimand as a first step to analysis, and explain how👇 journals.sagepub.com/doi/10.…

Defining estimand for the win ratio: Separate the true effect from censoring - Lu Mao, 2024

The win ratio has been increasingly used in trials with hierarchical composite endpoints. While the outcomes involved and the rule for their comparisons vary wi...

journals.sagepub.com
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Jonathan Bartlett retweeted
Christina Yap@ChristinaBYap
10 Jul 2024
Exciting job opportunity for a talented statistician to join us at the Early Phase & Adaptive Trials Group @ICR_CTSU as a Trials Methodologist! If you enjoy developing and implementing efficient trial methods to impact patients’ lives, come and join us! tinyurl.com/2fpad6z2
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Paul Newcombe (GSK) seminar 'Causal Machine Learning for Biomarker Subgroup Discovery in Randomised Trials' @LSHTM_datastats 16th July online and in person lshtm.ac.uk/newsevents/event…

Causal Machine Learning for Biomarker Subgroup Discovery in Randomised Trials

Decreasing costs of high-throughput ‘omics, as well as new technologies such as the Olink proteomics platform, has driven wider application in clinical trials, for example to inform precision medicine

lshtm.ac.uk
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Multiple imputation for missing covariates in the Fine & Gray model for competing risks, by @edbonneville. thestatsgeek.com/2024/06/05/…

Multiple imputation for missing covariates in the Fine & Gray model for competing risks

Competing risks and the Fine & Gray model In the setting of competing risks, one approach involves modelling the effects of covariates on the so-called cause specific hazard functions for each …

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Finally the debate is settled...., or not.
Kelly Van Lancker@KellyVanLancker
3 Jun 2024
Our (with @Frank_Bretz and Oliver Dukes) review article on covariate adjustment for marginal treatment effects is now published in Clinical Trials: doi.org/10.1177/174077452412…; along with a commentary by @f2harrell : doi.org/10.1177/174077452412… and our rejoinder: doi.org/10.1177/174077452412….
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Jonathan Bartlett retweeted
Theresa Smith@TheresaRSmith
29 May 2024
One week left to apply for a Health Data Science Post Doc with me as part of the @ai4cihub! bath.ac.uk/jobs/Vacancy.aspx… There is lots of flexibility in methodology you could pursue and an unbeatable team of collaborators!

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Jonathan Bartlett retweeted
Max Parmar@MaxParmarMRCUCL
24 Apr 2024
Join me for the 33rd Joint @LSHTM - @RoyalStatSoc Perspectives on Statistics in Medicine Annual Lecture (formerly Bradford Hill Memorial Lecture). 📅 26th June 2024 ⏲️ 1730-1830 (BST) 📍 John Snow Lecture Theatre, @LSHTM WC1E 7HT Link to join online: lshtm.zoom.us/j/98398749667#…
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