A new study from Johns Hopkins University researchers says that the first signs of stroke symptoms often go unnoticed — and the issue is more prevalent for minorities, women, and young patients. They examined data from emergency room visits, and determined that out of 188 stroke admissions, 12.7% had previously been to the ER within the preceding 30 days, but had received an unrelated diagnosis.

In a disproportionate number of these cases, patients were experiencing symptoms such as dizziness or headaches during their first visit to the emergency room, which are both stroke related symptoms. “This study provides some immediate suggestions to ER physicians who are evaluating patients with these symptoms — be more attuned to the possibility of stroke in younger, female, and non-white patients,” the research team explained.

The study’s leader, David E. Newman-Toker, says that even though strokes are less common with patients under the age of 45, ER doctors need to be more attuned to the possibility, especially when correlating symptoms are present. “ER physicians need to be more discerning and vigilant in ruling out stroke, even in younger people,” he says. This is the first large-scale study that quantifies stroke misdiagnosis.

Overall, minorities were 20-30% more likely to be misdiagnosed, and women were 33% more likely, suggesting that there might be a disparity in healthcare access to these groups. Other researchers have added to the discussion, citing how perception is often funneled, even by doctors, by common assumption. Because women cannot appear topless on most television networks, the “patients” people typically see on TV are disproportionately male — and the stroke symptoms men display, such as paralysis and trouble speaking, are what most of us are more likely to recognize.

There are over 124 million visits to the emergency room each year according to the CDC, and Newman-Toker believes that between 50,000 and 100,000 of these visits are missed strokes that result in a lack of pre-emptive care for patients. This lack of proper diagnostic assessment “can have dire consequences,” warns Newman-Toker.