by Elizabeth Hofheinz, M.P.H., M.Ed., September 3, 2019
Surprise! It’s another unplanned medical bill! Seeking to address this timely topic, a team of researchers from Stanford University set out to determine the incidence and financial consequences of out-of-network billing for inpatient admissions and emergency department visits. Their work, “Assessment of Out-of-Network Billing for Privately Insured Patients Receiving Care in In-Network Hospitals,” was published in the August 12, 2019 edition of JAMA Internal Medicine.
In looking at 5, 457, 981 inpatient admissions and 13, 579, 006 emergency department admissions between 2010 and 2016 in a large national sample of privately insured patients, they found that the incidence of out-of-network billing increased from 32.3% to 42.8% of emergency department visits, and the mean potential liability to patients increased from $220 to $628. For inpatient admissions, the incidence of out-of-network billing increased from 26.3% to 42.0%, and the mean potential liability to patients increased from $804 to $2040. 
Eric Sun, M.D., Ph.D. is with the Department of Anesthesiology, Pain, and Perioperative Medicine, at the Stanford University School of Medicine. A co-author on this work, Dr. Sun told OSN, “We were interested in this topic as the underlying issue of out-of-network billing is one that has received a lot of attention and there are legislative efforts aimed at protecting consumers/patients.”
The authors wrote, “Among all 13, 579, 006 ED visits to in-network hospitals, 39.1% resulted in an out-of-network bill. The incidence of out-of-network billing among ED visits increased from 32.3% in 2010 to 42.8% in 2016. The potential financial responsibility associated with out-of-network billing also substantially increased, from a mean of $220 in 2010 (median, $107; interquartile range [IQR], $5-$300) to a mean of $628 in 2016…”
Dr. Sun commented to OSN, “We were surprised to see how common out-of-network billing is, and the extent to which it has risen over the past few years.”
Asked what types of protections might need to be implemented, Dr. Sun noted, “While it is beyond the scope of our paper to provide specific recommendations, our paper argues for the need to implement laws and policies that will protect patients.”