Thread by @benryanwriter

In a bold new paper, three academics criticize how #longCovid has been studied. They say the term itself is so ill defined it should be discarded and that the studies have often been riddled with bias.
By: @VPrasadMDMPH @TracyBethHoeg @ShamezLadhani
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ebm.bmj.com/lookup/doi/10.…

#LongCovid prevalence, @VPrasadMDMPH @TracyBethHoeg @ShamezLadhani argue in @BMJ_EBM, has been over-estimated due to "overly broad definitions, lack of control groups, inappropriate control groups and other methodological flaws." This has caused "undue concern and anxiety." 2/

The paper's authors define #longCovid as a syndrome or individual symptoms that are a direct effect of Covid lasting at least 12 weeks. But they advise others in their field to discard the term "and instead more narrowly define certain post-Covid syndromes or symptoms." 3/

@VPrasadMDMPH, @TracyBethHoeg and @ShamezLadhani criticize four international health organizations, including the @CDCgov, @WHO and others, for not requiring a causal link between coronavirus infection and long Covid (aka post-acute sequelae of Covid-19, or PASC). 4/

A review paper found that, of studies that looked at long Covid interventions, only 54% required that the members of the study have lab-confirmed Covid. One study found that self reporting LC was more strongly tied to a belief of having had Covid than a Covid diagnosis. 5/

Long Covid, @VPrasadMDMPH, @TracyBethHoeg and @ShamezLadhani write, also suggests a permanent condition. However, there is good evidence that the associated symptoms do indeed improve over time. 6/

@VPrasadMDMPH, @TracyBethHoeg and @ShamezLadhani criticize the lack of control groups in many #longCovid studies. 7/

@VPrasadMDMPH, @TracyBethHoeg and @ShamezLadhani criticize many #longCovid studies for having what they characterize as inappropriately matched control groups. 8/

@VPrasadMDMPH @TracyBethHoeg @ShamezLadhani suggest improvements to long Covid research:
Avoid: misclassification bias, selection bias, detection bias, confounding by underlying health, information bias, sampling bias and mischaracterization; and reduce diagnostic ambiguity. 10/

This is one of the most stunning examples, if not the most egregious example, of someone with a doctorate exaggerating the threat of #longCovid and sowing fear and panic.

Ladies and gentlemen, I give you @fitterhappierAJ: