@EpiEllie's Threads
An interesting question that arises from that attractiveness & endometriosis study, is to what extent should researchers be considering the history of other published articles when choosing a journal vs assessing the audience that it reaches?
Are there any journals that have really never ever published a bad take study? Does boycotting journals penalize early career researchers, for example by imposing a requirement to spend extra time reviewing historic articles before choosing where to submit?
Could an argument be made that journals that have good circulation & publish bad takes might even be *more* important places to publish because their audiences may have more of a need to be educated on changing norms in the field?
Whatcha doing twitter? It’s 2:30am & I cant sleep...
Quick 15 min poll: can’t sleep, what should I do?
Welp, looks like you’re in agreement that I should go read, so I’m putting down twitter
Hey, #epitwitter allow me to introduce the #epigif! A whole new level of #epicartoon to inform and delight 😆
If you’d prefer a non-gif version, the inaugural #epigif is based on this Medium post of mine👇🏼 link.medium.com/Bic3m9sw3Y
So, what do you think? More #epigifs? Just stick with #epicartoons? Other ideas?
A #tweetorial about defining your protocol for per-protocol effects, using the LIVE trial of personalized mechanical ventilation for acute respiratory distress syndrome (ARDS).
h/t @otavio_ranzani @f_g_zampieri
Original article in @LancetRespirMed👇🏼
thelancet.com/journals/lanre…
h/t @otavio_ranzani @f_g_zampieri
Original article in @LancetRespirMed👇🏼
thelancet.com/journals/lanre…
First, what is the research question?
The Lung Imaging for Ventilator Setting (LIVE) trial was designed to test if choosing ventilator settings based on lung features (focal vs non-focal) could help improve ARDS survival, relative to a one-size-fits-all ventilation approach.
The Lung Imaging for Ventilator Setting (LIVE) trial was designed to test if choosing ventilator settings based on lung features (focal vs non-focal) could help improve ARDS survival, relative to a one-size-fits-all ventilation approach.
Of 1080 potential participants w/ ARDS assessed for eligibility, 420 were eventually randomized to either the control arm (one-size-fits-all settings) or personalized arm (settings based on focal vs non-focal).
The treatment matrix is sorta complex, so I’m pasting it here👇🏼
The treatment matrix is sorta complex, so I’m pasting it here👇🏼
I have a matching question, #epitwitter:
In cohort studies, matching is supposed to control for confounding so you don’t need to adjust for the matching factors, but in case-control studies, matching just improves efficiency & you still need to adjust for matching factors... 1/3
In cohort studies, matching is supposed to control for confounding so you don’t need to adjust for the matching factors, but in case-control studies, matching just improves efficiency & you still need to adjust for matching factors... 1/3
In a DAG, the case-control situation seems clear to me👇🏼... selection is a consequence of the outcome and the match factor and is therefore a collider.
So, makes sense that we need to adjust for the match factor in a case-control study to block that path & the confounding. 2/3
So, makes sense that we need to adjust for the match factor in a case-control study to block that path & the confounding. 2/3
But, when I draw a similar DAG for a cohort study, isn’t selection a consequence of *exposure* & the match factor & therefore *still* a collider?
Why don’t we need to adjust for the match factor as a confounder / open collider path in a cohort study? What am I missing? 3/3.
Why don’t we need to adjust for the match factor as a confounder / open collider path in a cohort study? What am I missing? 3/3.
Yesterday, @BUSPHEpi #epibookclub was joined by Dr Nancy Krieger
It was so great to be able to discuss with her in person! I definitely understand so much more now!
So, here’s a thread of our convo👇🏼
#EpiPeoplesHealth
It was so great to be able to discuss with her in person! I definitely understand so much more now!
So, here’s a thread of our convo👇🏼
#EpiPeoplesHealth
The 1st question was posed by @ProfMattFox: what was Dr Krieger’s goal in writing this book?
Long story short: “this book is what I wish I had been taught as a student”
She encouraged students to explore their interests even if they don’t fit traditional boundaries of the field
Long story short: “this book is what I wish I had been taught as a student”
She encouraged students to explore their interests even if they don’t fit traditional boundaries of the field
Dr Krieger said something which really resonated with me & is a big part of why I #epitwitter
“The role of educators is to transmit the lessons you’ve learned to others”
If we dont share what we’ve learned, be it theory or methods or experiences, we’re not fulfilling our roles.
“The role of educators is to transmit the lessons you’ve learned to others”
If we dont share what we’ve learned, be it theory or methods or experiences, we’re not fulfilling our roles.
I’m literally melting, #epitwitter! So, let’s have some #epifoodwar fun!
What’s your favorite cool-down treat?
What’s your favorite cool-down treat?
If you had to pick only one of these 4 ice cream flavors to eat for the rest of forever, which would it be?
This is a #epifoodwar, so you gotta pick one! No 5th options allowed! 😆
This is a #epifoodwar, so you gotta pick one! No 5th options allowed! 😆
At #ser2018, I saw an iced custard stand which sounded weird but now I regret not trying. Where can I get some near Boston?
What other variants on ice-based dessert treats have I never heard of? Share your local fav!!
#epifoodwar
What other variants on ice-based dessert treats have I never heard of? Share your local fav!!
#epifoodwar
It’s week 2 of the #EpiPeoplesHealth #epibookclub, so that means it’s time to talk about chapter 2!
This week is about early theories of the patterns and occurrence of disease.
I’m gonna do a short recap & then @nabuelezam and I will have some discussion questions all week!
This week is about early theories of the patterns and occurrence of disease.
I’m gonna do a short recap & then @nabuelezam and I will have some discussion questions all week!
In Ch 2, Dr Krieger introduces us to 4 early theories of disease.
The first is the humoral theory of disease causation of the ancient Greeks.
Under this theory, health requires balance of the 4 humors, which are in turn affected by the environment & the season.
The first is the humoral theory of disease causation of the ancient Greeks.
Under this theory, health requires balance of the 4 humors, which are in turn affected by the environment & the season.
Every person has their own natural state within the system, and based on whether you are more yellow bile or more pleghm or less black bile, there are different expectations for how your health will change throughout the year & following life events... a humoral disease horoscope
I’ve been getting a lot of new followers lately, so how about an #epitwitter #ScholarSunday so newcomers can get connected to our lovely community!
Here’s a thread of some of my suggestions for who to follow & why! Add your own in the comments👇🏼
Here’s a thread of some of my suggestions for who to follow & why! Add your own in the comments👇🏼
Looking for some academic career advice? Have questions about writing grants? Want tips on making delicious pizza or pie? Head on over to @BillMiller_Epi!
Want support for how to #liveyourbestlife, learn to say ‘no’, or throw an amazing party? You’ll be wanting to follow @lisabodnar!
Related to the discussion in this thread👇🏼, here’s a short thread on something I else I’ve been mulling over lately re: Hill’s criteria
#epibookclub #EpiPeoplesHealth #epitwitter
#epibookclub #EpiPeoplesHealth #epitwitter
Is there any way in which they be considered a theory of epidemiologic causation?
If not, & they’re instead just tool for thoughtful evaluation of evidence, can they be applied to non-quantitative evidence or non-causal questions?
Heard about the #EpiPeoplesHealth #epibookclub and want to know how it works? This is the thread for you!
1. We’re reading Nancy Krueger’s Epidemiology and the People’s Health.
2. We started this week, and are reading one chapter per week all summer.
1/n
1. We’re reading Nancy Krueger’s Epidemiology and the People’s Health.
2. We started this week, and are reading one chapter per week all summer.
1/n
3. @nabuelezam and I are co-moderating. This means we’ll post our thoughts, discussion questions, reflections each week.
4. To participate, comment on those threads or post ur own.
5. Make sure to include the tags: #epibookclub and #EpiPeoplesHealth so we can find ur tweets!
2/n
4. To participate, comment on those threads or post ur own.
5. Make sure to include the tags: #epibookclub and #EpiPeoplesHealth so we can find ur tweets!
2/n
6. Follow me & @nabuelezam to make sure you don’t miss our threads!
7. Don’t forget to check out the tags to see & discuss other’s posts
8. In the twitter web version, you can save the hashtags as searches for easy access anywhere, anytime.
9. Last but not least, have fun!
3/n
7. Don’t forget to check out the tags to see & discuss other’s posts
8. In the twitter web version, you can save the hashtags as searches for easy access anywhere, anytime.
9. Last but not least, have fun!
3/n
What is @HarvardChanSPH doing about this, @HarvardChanDean?
And while we’re at it, what has @HarvardChanSPH done for Flint, Michigan?
#thisispublichealth #FlintWaterCrisis
And while we’re at it, what has @HarvardChanSPH done for Flint, Michigan?
#thisispublichealth #FlintWaterCrisis
And then maybe head over to @LittleMissFlint’s page & help her with her latest fundraising goal
#FlintWaterCrisis
#FlintWaterCrisis
At #ser2019, @zepidpy gave a very nice talk about how to avoid bias from left truncation.
But the whole talk I thought he meant left censoring. Turns out censoring & truncation are two completely different ideas! Who knew?!
In case you also didn’t, here’s a #tweetorial!
But the whole talk I thought he meant left censoring. Turns out censoring & truncation are two completely different ideas! Who knew?!
In case you also didn’t, here’s a #tweetorial!
First, let’s make sure we’re all on the same page.
The setting: longitudinal data
The problem: not all data are observed
The setting: longitudinal data
The problem: not all data are observed
So, what is censoring?
Censoring is when you don’t know exactly when (or if) the outcome variable happens for someone.
Censoring is when you don’t know exactly when (or if) the outcome variable happens for someone.
At the #SER2019 plenary, @sandrogalea & @_MiguelHernan are *not* debating about #socialepi and #causalinference because, despite what everyone thinks, they don’t actually disagree!
So, instead, they’re here to set the record straight.
So, instead, they’re here to set the record straight.
If we’re talking about #socialepi, we need a definition. @sandrogalea starts broad: “social epi is the health effects of forces ‘above the skin’” aka everything outside your body
And similarly, #causalinference is about drawing conclusions about causal effects.
My next session on methods for complex data is happening now in Nicollet A!
I’ll be talking about pragmatic trials & per-protocol effects.
I’ll be talking about pragmatic trials & per-protocol effects.
But first, @JessiePBuckley for Alex Keil on a new g-computation approach for causal effects of exposure mixtures.
One benefit over existing approaches: unlike weighted quartile sums regression, this method doesn’t assume all components work in the same direction.
One benefit over existing approaches: unlike weighted quartile sums regression, this method doesn’t assume all components work in the same direction.
There’s a preprint, so I’ll for sure be checking that out! The link is: arxiv.org/abs/1902.04200
Neck tattoo poll!
Excited to hear @lisabodnar & @ProfMattFox’s #SPER2019 keynote!! Just as soon as the technical issues get fixed 😬😬
Is twitter a dumpster fire?
Not #epitwitter!!
It’s finally summer, which means it’s time for the next #epibookclub!
Our book will be Epidemiology & the People’s Health by Nancy Krieger
Get your copy now & we’ll kick off reading once #SER2019 is done!
#EpiPeoplesHealth
Our book will be Epidemiology & the People’s Health by Nancy Krieger
Get your copy now & we’ll kick off reading once #SER2019 is done!
#EpiPeoplesHealth
For those of u new to #epibookclub, here’s how it works:
•We read 1 chapter / week
•each week, I’ll post a recap + thoughts, qs, etc
•everyone joins in w/ thoughts, qs etc
•tag ur posts with #EpiPeoplesHealth
•I’m enlisting @nabuelezam to help moderate, so follow her too!
•We read 1 chapter / week
•each week, I’ll post a recap + thoughts, qs, etc
•everyone joins in w/ thoughts, qs etc
•tag ur posts with #EpiPeoplesHealth
•I’m enlisting @nabuelezam to help moderate, so follow her too!
Since I’ve been traveling a lot, I’ve had so many convos with uber drivers, & I thought I’d share some of them.
The good news: no one thought epidemiologists study skin.
The bad news: no one had any idea that epidemiologists even existed.
The good news: no one thought epidemiologists study skin.
The bad news: no one had any idea that epidemiologists even existed.
Driver: so, what do u do?
Me: I’m an epidemiologist, we study why people get sick & what doctors can do to make people healthy again.
D: so, ur like... better than a doctor?!? They are so full of themselves! This is the best day of my life! I wish I could give you a free ride!
Me: I’m an epidemiologist, we study why people get sick & what doctors can do to make people healthy again.
D: so, ur like... better than a doctor?!? They are so full of themselves! This is the best day of my life! I wish I could give you a free ride!
Driver: so, u study healthcare? We have those great community clinics now. I just went to the doc for the 1st time in 30 years.
Me: oh wow, no insurance?
D: Nah, just I don’t trust doctors. My dad neither. He was in some study on syphilis.
Me:...Tuskegee??
D: yeah that’s the one.
Me: oh wow, no insurance?
D: Nah, just I don’t trust doctors. My dad neither. He was in some study on syphilis.
Me:...Tuskegee??
D: yeah that’s the one.
Our #ACIC2019 session is all about the #targettrial framework!
I kicked things off with a discussion of what causal effect we should estimate & the implications for our analyses.
Here’s a gif of my slides!
I kicked things off with a discussion of what causal effect we should estimate & the implications for our analyses.
Here’s a gif of my slides!
Next up, @lucia_petito gives a nice example of implementing the #targettrial framework to emulate an #RCT using electronic health care data.
One important concern: immortal time bias! 🧛🏻♀️🧛🏼♂️🧛🏻♀️🧛🏼♂️
One important concern: immortal time bias! 🧛🏻♀️🧛🏼♂️🧛🏻♀️🧛🏼♂️
Our next #targettrial example is from @elliecaniglia.
She explains some of the challenges of looking at the effect (if any) of statins on preventing dementia among older adults.
When time zero isn’t fixed, try emulating a sequence of target trials.
She explains some of the challenges of looking at the effect (if any) of statins on preventing dementia among older adults.
When time zero isn’t fixed, try emulating a sequence of target trials.
Our new paper on using distance to care as an exposure or instrument and why it often violates all of the causal inference assumptions is now online at @AmJEpi! Check it out and stay tuned for a tweetorial!
cc @elliecaniglia
academic.oup.com/aje/advance-ar…
cc @elliecaniglia
academic.oup.com/aje/advance-ar…
One of the most fun parts of working on this paper was making an #rstats shiny app to help readers play around with the different sensitivity analyses we discuss.
Check it out here... but maybe not all at once because then the server might crash 😆
emurray.shinyapps.io/distanceApp/
Check it out here... but maybe not all at once because then the server might crash 😆
emurray.shinyapps.io/distanceApp/
Inspired by a question from @Econdoor , a #tweetorial about instrumental variables and the exclusion restriction.
#econtwitter #epitwitter #FOAMed
#econtwitter #epitwitter #FOAMed
First, instrumental variables and causal graphs:
An instrument is a special type of variable that is associated (causally or otherwise) with the exposure you’re interested in.
The directed acyclic graph (DAG) below shows the basic required structure.
An instrument is a special type of variable that is associated (causally or otherwise) with the exposure you’re interested in.
The directed acyclic graph (DAG) below shows the basic required structure.
There are three key requirements for a variable to be an instrument:
•it is associated with the exposure
•it is not associated with the outcome EXCEPT through exposure
•it does not share any causes with the outcome (ie unconfounded).
We have these 3 properties in our DAG👇🏼
•it is associated with the exposure
•it is not associated with the outcome EXCEPT through exposure
•it does not share any causes with the outcome (ie unconfounded).
We have these 3 properties in our DAG👇🏼
A short #tweetorial about how to quantify harms (or benefits) to help make decisions, inspired by that @BillGates tweet...
#epitwitter #FOAMed
#epitwitter #FOAMed
If we want to use evidence to make decisions, the first step is to describe the problem. And the first step in describing the problem is to count how often it happens.
If we want to decide how to spend money to prevent the most death, counting deaths from shark bites & mosquito bites is a good place to start.
As Bill Gates did, we’ll find the number of mosquito bite deaths is much higher! Mosquitos are probably a good place to spend our money!
As Bill Gates did, we’ll find the number of mosquito bite deaths is much higher! Mosquitos are probably a good place to spend our money!
Have you read @AmJEpi’s Future of Epi articles? Let’s discuss!
Thread w/ links & some thoughts on each, starting here. I’ll add to it as I read them.
#EpiTwitter
Thread w/ links & some thoughts on each, starting here. I’ll add to it as I read them.
#EpiTwitter
First up... Epidemiologists of the Future: Data Collector or Scientist? By Lewis Kuller
My takehome from this article is the author thinks #epimethods are key to making science out of big data, -omics data, etc. I definitely agree with that!
academic.oup.com/aje/advance-ar…
My takehome from this article is the author thinks #epimethods are key to making science out of big data, -omics data, etc. I definitely agree with that!
academic.oup.com/aje/advance-ar…
Next up... On Being an Epidemiologist by Jonathan Smat & Alistair Woodward
The authors call for more translational epi work & for better tools for “etiology of the future”, especially topics like forecasting impacts of climate change.
academic.oup.com/aje/advance-ar…
The authors call for more translational epi work & for better tools for “etiology of the future”, especially topics like forecasting impacts of climate change.
academic.oup.com/aje/advance-ar…
