Share this page!

Enter URL or ID to Unroll

You can paste full URL like: https://x.com/threadreaderapp/status/1644127596119195649
or just the ID like: 1644127596119195649

How to get URL link on X (Twitter) App

  1. On the Twitter thread, click on or icon on the bottom
  2. Click again on or Share Via icon
  3. Click on Copy Link to Tweet
  4. Paste it above and click "Unroll Thread"!
  5. More info at Twitter Help
Dr Ellie Murray, ScD Profile picture
@EpiEllie
Dec 6 • 4 tweets • 1 min read Twitter logo Read on Twitter
Me, an epidemiologist: research shows widespread mask use reduces respiratory infections

Them, a rando: OMG WHY DO YOU WANT EVERYONE TO ALWAYS MASK EVERYWHERE FOREVER?!!!!
Me, an epidemiologist: research shows widespread mask use reduces respiratory infections

Them, another rando: oh yeah? Well one time I saw a mask and then I got sick, so how do you explain that, huh?!
Me, an epidemiologist: research shows widespread mask use reduces respiratory infections

Them, yet another rando: UUUGH, WHY ARE YOU STILL SO OBSESSED WITH DISEASES?!! WHAT ARE YOU EVEN?!!
Me, an epidemiologist: research shows widespread mask use reduces respiratory infections

Them, once again, another rando: But my graph shows mask mandates followed [ed note: 12+ months later] by a rise in covid. Check mate! Ha!

• • •

Missing some Tweet in this thread? You can try to force a refresh
　

Keep Current with Dr Ellie Murray, ScD

Dr Ellie Murray, ScD Profile picture

Stay in touch and get notified when new unrolls are available from this author!

Read all threads

This Thread may be Removed Anytime!

PDF

Twitter may remove this content at anytime! Save it as PDF for later use!

Try unrolling a thread yourself!

how to unroll video
  1. Follow @ThreadReaderApp to mention us!

  2. From a Twitter thread mention us with a keyword "unroll"
@threadreaderapp unroll

Practice here first or read more on our help page!

More from @EpiEllie

Dr Ellie Murray, ScD Profile picture
Dec 5
When people talk about masks & mask mandates for preventing respiratory infections, they love to talk about improper mask wearing.

And it’s true not everyone wears good masks correctly. But it’s also true that MOST people wear good masks well.

How many is most? About 85%.
Data from *Kentucky* show that during their mask mandates, 95% of people in indoor public spaces were seen to be wearing any mask.

And 87% of people were wearing masks that fully covered mouth and nose.

journals.plos.org/plosone/articl…
We did a separate study in Boston right around the same time — without knowing the Kentucky study was even happening.

What did we find?

95% of people were wearing masks in indoor public spaces. And 85% had them correctly over mouth & nose.
Read 9 tweets
Dr Ellie Murray, ScD Profile picture
Nov 13
Out now in Osteoarthritis and Cartilage: our new paper presents a graphical causal model for treatment of pain in knee osteoarthritis.

Open access link: oarsijournal.com/article/S1063-…
Image
We outline a 6-step process for creating causal graphical models using scientific evidence and expert knowledge.

Identify core variables, create a list of potential covariates, conduct a semi-systematic literature review, discuss with experts, synthesize, and visualize. Image
What do we mean by "semi-systematic" literature review?

Like a systematic review, you begin with a carefully created search hedge: key words for your exposure, outcome, and/or other core variables, combined with your covariate list.
Read 22 tweets
Dr Ellie Murray, ScD Profile picture
Oct 3
Nate Silver’s blog👇🏼 is a nice example of using triangulation for causal attribution.

He lays out starting assumptions, then varies his assumptions to see what changes.

He’s not estimating a causal effect. Instead, he’s using descriptive stats to hypothesize about the cause.
Despite this type of triangulation being a key and crucial part of science (and just like, life!), we often don’t spend enough time teaching students how to do it in a reasoned and systematic way.
In epidemiology, triangulation is often pitted against causal effect estimation. But they have different purposes.

Causal effect estimation is critical when we want to know the *size* of an effect.

Triangulation helps us answer the question: is this likely a cause *at all*?
Read 16 tweets
Dr Ellie Murray, ScD Profile picture
Sep 19
THINK LIKE AN EPIDEMIOLOGIST:
Science is not magic. It always requires assumptions.

When done perfectly, some types of studies make fewer assumptions. But no one’s perfect.

We can’t decide quality from study type alone: a good observational study can be better than a bad RCT. A continuum of bias in study design. At the top, a double-headed arrow is labeled “unbiased” on the left with “ideal randomized controlled trial” as an example and “intractably biased” on the right with “relying on ‘gut feeling’” as an example. Below the arrow are 4 overlapping bars with relative positions of 4 main study types. From left to right: explanatory randomized trials, pragmatic randomized trials, observational studies, simulation studies. Each study type covers a range of quality. For each of the four types listed, under the very best version of the design possible that des...
@benedictecallan I like to call this the “mad scientist target trial framework”.

Not “what RCT would you do”, as a starting point for observational study design.

What experiment would the mad scientist version of you, as a start for designing any study, experiment, observation, or model.
@Kcummins760 This is, in fact, a fatal flaw in the GRADE criteria approach to evidence synthesis.

Which is the topic of a paper of mine currently languishing in the morass that is peer-review. Turns out people don’t like it when you point out major flaws in foundational research tools, 🤷🏼‍♀️
Read 5 tweets
Dr Ellie Murray, ScD Profile picture
Sep 5
Our @NEJM study showed school mask mandates *reduce* COVID illness & absences.

Others disagreed. But we take scientific critique seriously. So we checked everything suggested to us. And now we’ve published an updated Appendix with the details.

Our results hold: Mandates work.
Here’s the link to our original study:

nejm.org/doi/full/10.10…
And here’s the updated Appendix with all our new sensitivity analyses, plus some additional explanation about what types of causal questions we can and can’t answer with these data. 👇🏼

nejm.org/doi/suppl/10.1…
Read 7 tweets
Dr Ellie Murray, ScD Profile picture
Aug 27
SUNDAY PUBLIC HEALTH MINUTE:

Ever heard “it takes a village to raise a child”?

Well, it also takes a village to start an outbreak. And to stop one.

How do we teach our communities better public health? The answer: public health literacy.

A 🧵
What is “public health literacy”?

Despite the fact that ensuring good public health is one of the most important functions of society, it turns out no one* has ever really defined “public health literacy”!

___
*We’ve found <5 scientific articles ever on public health literacy!
To address this major gap, our team enlisted the help of MPH student Maggie Burkhardt (she graduated May 2023 🥳) to do a deep dive on anything and everything that was possibly related to this idea.
Read 12 tweets

Did Thread Reader help you today?

Support us! We are indie developers!

This site is made by just two indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3/month or $30/year) and get exclusive features!

Become Premium

Don't want to be a Premium member but still want to support us?

Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal

Or Donate anonymously using crypto!

Ethereum

0xfe58350B80634f60Fa6Dc149a72b4DFbc17D341E copy

Bitcoin

3ATGMxNzCUFzxpMCHL5sWSt4DVtS8UqXpi copy

Thank you for your support!

Follow Us on Twitter!

Send Email!

:(