In order to actually drive good outcomes, evidence-based practice requires a decent methodological framework

‘Evidence-based practice’ is a term that needs to be defined clearly; we need agreement about what such a term actually means.

A recent Bloomberg article about Sweden reminds us that such a term must be used with care, as otherwise it serves no useful purpose.

In some circumstances, the term may be brandished with a flourish, in a manner that may be totally untethered from reality. Such a use of the term, in which rhetoric takes precedence over reality, is misguided and harmful.

Consider an April 4, 2020 Bloomberg article entitled: “Sweden girds for thousands of deaths amid laxer virus response.”

An excerpt reads:

Sweden’s top epidemiologist, Anders Tegnell, says the goal in his country, like everywhere else, is to “flatten the curve” to avoid overwhelming hospitals. As of Thursday [April 2, 2020], he said that curve is “starting to become somewhat steeper, but overall” remains “fairly flat.”

But Covid-19 comes with so many unknowns that Sweden’s approach has some of its own experts worried.

“They are used to making evidence-based decisions, but that doesn’t work for a pandemic like this, where key coordinates are unknown,” said Claudia Hanson, a Stockholm-based senior lecturer in global public health.

The history of social isolation as an intelligent response to outbreaks like Covid-19 is compelling. Roughly a century ago, when the world was dealing with the Spanish flu, two U.S. cities ended up becoming case studies due to their very different approaches. In Philadelphia, the city staged a parade with 200,000 people a week and a half after the first case was identified, and quickly saw a sharp spike in the death rate. In St. Louis, officials imposed tough social distancing rules; the death rate there was less than half Philadelphia’s.

To state the matter another way, it’s imperative to base decisions on the evidence, but first we must take into account a wide range of uncertainties. Sweden has to date purported to follow the evidence, but as is the case in some other jurisdictions, it has until recently argued that physical distancing is not a crucial step in containment of the virus.

Physical distancing

As I’ve noted at previous posts, physical distancing is a critical component in countries that have adopted an evidence-based approach to dealing with COVID-19.

We can say, in this context, that the pandemic gives rise to three potential responses:

1. An evidence-based approach
2. An opinion-based approach
3. An approach in which evidence and opinion are intermingled

The current post  focuses on the third approach, in which evidence and opinion are intermingled

Among previous posts discussing the three potential responses are:

Taiwan has got it right

and

Sweden’s approach to COVID-19 has been changing

A March 23, 2020 New York Times article is entitled: “The virus can be stopped, but only with harsh steps, experts say.”

This article is useful, because it provides a framework for separating evidence from opinion.

The articles notes that success in dealing with the pandemic “will take extraordinary levels of coordination and money from the country’s leaders, and extraordinary levels of trust and cooperation from citizens.”

Key points from the article can be summarized as follows:

1. Scientists must be heard
2. Stop transmission between cities
3. Stop transmission within cities
4. Fix the testing mess
5. Isolate the infected
6. Find the fevers
7. Trace the contacts
8. Make masks ubiquitous
9. Preserve vital services
10. Produce ventilators and oxygen
11. Retrofit hospitals
12. Decide when to close schools
13. Recruit volunteers
14. Prioritize the treatments
15. Find a vaccine
16. Reach out to other nations

In the American South, physical distancing has in many cases been ignored

An April 3, 2020 New York Times article is entitled: “In the American South, a perfect storm is gathering.”

The article illustrates the third approach, in which evidence and opinion are intermingled.

The subhead reads: “In states with many uninsured citizens, few hospitals and leaders who have not required citizens to stay home, a disaster is looming.”

An excerpt (I have omitted embedded links) reads:

But it had to be done. Nashville’s courts and schools were already closed, but the crowds on Lower Broadway, the heart of Nashville’s tourist district, showed no sign of dissipating. “Downtown Nashville is undefeated,” tweeted a visitor posting a video of music fans crowded onto a dance floor. Even after the Nashville Board of Health voted unanimously to shut the honky-tonks down, several bar owners said they would not comply unless ordered to do so by the governor of Tennessee.

Such orders have been slow in coming here, and in nearly every other state in the American South. Tennessee governor Bill Lee was slow to end the legislative session and send members of the Tennessee General Assembly home to their districts, slow to close public schools, slow to suspend church services, slow to shutter restaurants and gyms.

Many city charters in Tennessee prevent local leaders from issuing their own orders, and mayors begging for a statewide directive got none. Chaz Molder, mayor of Columbia, Tenn., urgently called on Mr. Lee to issue a statewide stay-at-home order: “One state, one response,” he wrote on Twitter. But in a conference call on March 16, Mr. Lee told local leaders around the state that mandates weren’t necessary to enforce social-distancing guidelines: “We’re not issuing orders, we’re issuing guidance and strong suggestions,” Mr. Lee said. “We don’t have to mandate people not do certain behavior because Tennesseans follow suggestions.”

Larger topic of public health leadership

A subsequent post, which addresses public health leadership cultures, is entitled:

Sobering thoughts, regarding distinctions in public health leadership culture