That just means there's no diagnostic test, not that the symptoms aren't real! There aren't biomarkers for chronic pain, either, which presents a serious problem for people seeking treatment.

This is the "I closed your bug report because it works on my machine" of medicine.

The challenge is when physical symptoms aren’t backed up by measurements of actual function.

When people complain of lung or heart problems but all tests are normal (oxygen levels, cardiac efficiency, lung capacity, exercise tolerance).

When people claim cognitive decline yet all measures of cognitive ability are normal.

It would point to a strong psychological component for at least some people - which was found in the study. Symptoms were correlated with those having a history of anxiety disorders (prior to Covid).

There was also another study (I can’t find it right now) of self-reported long Covid suffers.

They ran tests and many of them had never even been infected with Covid..ever.

This isn’t to say that post-viral syndromes aren’t real. But it does suggest that self-reporting isn’t all that accurate.

It raises entirely valid questions, none of which should undermine the patient's experience. Listen to the patient: they're telling us something.

To anticipate: "Objective" measures are of course useful, but only form part of any picture.

Of course. If the patient is experiencing symptoms those should be addressed.

And this data helps to narrow down possible treatments based on solid data with regards to system dysfunction.

As a software engineer I have a wide variety of tests to my disposal. Still, there are things which I would not be able to test for. EM interference between chips in a data center. Row-hammer attacks. Clock jitter. My running processes would fail, but there is no way for me to prove a specific cause.

So we search deeper. And sometimes we find something: https://mylongcoviddiaries.medium.com/i-finally-have-a-diagn...