Keep in mind, the study entirely excluded non-English speakers, suggesting that the problem of patients not understanding the doctor’s orders is likely even greater.

The average discharge note was written at about a 10th grade level, the study found.

The good news is that the ability of a patient to understand the instructions did not correlate with a higher likelihood of hospital readmission.

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But it was a relatively small study; it’s possible a larger-scale study would discover clearer consequences of patients misunderstanding their notes.

“Even if patients believe they understand what occurred during their hospitalization and the instructions they are to follow upon dismissal, they can become confused after they leave the hospital environment as their memory can be clouded by medications they were administered, the stress of hospitalization, and, particularly within our patient population, traumatic brain injuries such as concussions,” Dr. George Zielinski, a Mayo Clinic surgeon who led the study, told Reuters.

The solution to the communication gap is not just for Americans to improve their reading skills. Doctors and other health care providers have a duty to communicate with patients in a way they can understand, say the researchers.

“Patient discharge notes are written at too advanced of an educational level,” they conclude. “In order to ensure patient comprehension, dismissal notes should be re-written to a 6th-grade student.”