All this highlights one of the great paradoxes of modern medicine: Some of the most common ailments remain some of the least understood.

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Due to a host of reasons, doctors and medical professionals still struggle to answer seemingly basic questions about concussions. “For the vast majority of concussions that are treated in the E.R. and in the trainer’s room, there is currently no prognostic test available,” said Robert Siman, a researcher and professor of neurosurgery at the University of Pennsylvania.

This is partly because the very diagnosis and monitoring of a concussion are based on an amalgam of imperfect tests, none of which fully examines the underlying pathophysiological nature of the injury. New research assessing the severity of concussions through blood testing may eventually help unlock new methods for understanding such injuries, but further trial is still required. For now, when a person is suspected of having sustained a mild traumatic brain injury, they undergo a series of cognitive and symptom-based assessments. How is your memory? Are you experiencing headaches? Nausea? Dizziness? Loss or lack of balance? Sensitivity to light or sound? Patients are often asked to fill out a scorecard ranking the severity of their symptoms, and as symptoms vanish, they return to normal activity.

“We always look at mind, body, and spirit,” said R. Robert Franks, an osteopathic family physician and spokesperson for the American Osteopathic Association. “It’s an all-encompassing pathology, and you have to look at the complete patient with this, you have to look balance, you have to look vision, you have to look cognition, you have to look at neck pain for whiplash type injury, you have to look at anxiety, depression … you have to look at sleep. We focus so much on headache and dizziness, and those other symptoms kind of go by the wayside, but the athlete is not ready to go until we have all of those in check.”

In more serious cases of brain injury, imaging from a C.T. scan or an M.R.I. can reveal specifics, like an intracranial bleed, which takes longer to heal. But in the majority of patients suffering from concussions, it can be difficult if not impossible to say whether they will be part of the 80 to 90 percent that recovers quickly, or the latter 10 to 20 percent that needs more time. For the most part, doctors end up cobbling together an understanding of a person’s injury through subjective reports, brain imaging, and other tests. “So you can see a number of different things,” said Alison Cernich, the director of the National Center for Medical Rehabilitation Research at the NIH, “not just through cognitive testing and not just through asking the person, but by looking at some of the other symptoms.”

Symptom-scoring became the primary means for doctors to assess me as the weeks of my concussion wandered on. Every other day I filled out a questionnaire ranking my various ailments on a scale of 1 to 6. This process proved problematic: What is a 4, really? Individuals have different pain thresholds and rankings; and those individual rankings are easily subject to shift. At the beginning of my concussion I recall putting down 1s and 2s. But as the days wore on I realized I had been swayed by my own optimism. Now I really was a 2, back then I should have been a 4! I would suddenly realize that I felt better, but I didn’t have the numeric wherewithal to express my progress because I had skewed my initial ranking. Not only is such a scale nebulous and subjective, it relies on the perception of someone with a head injury. Even today, fully healed, a 1-to-6 scale would prove difficult for me to navigate. But imagine trying to fill out the scorecard while concussed. Imagine, while brain-addled, trying to give doctors, or anyone for that matter, a clear picture of your mind and body. And then imagine that picture serving an important role in your overall diagnosis.