Hospitalists are more likely than other physicians to choose high-intensity codes for inpatient care, study finds

During a 10-year period, hospitalists were more likely to bill at the highest severity level for initial, subsequent and discharge encounters, and the disparity increased over time.

The billing and coding practices of hospitalists may contribute to the rising cost of hospital care in the U.S., according to a new study.

For a study published in JAMA Health Forum, researchers examined more than 4 million Medicare fee-for-service claims spanning 2009 through 2018 to compare the proportion of “high-severity” billing between hospitalists and non-hospitalists. Physicians were compared within the same hospital and the data was adjusted for patient demographics and comorbidities.

Assessing initial, subsequent and discharge encounters, researchers with Brigham and Women’s Hospital, Harvard and UCLA found that hospitalists billed “a significantly higher proportion” of encounters as high-severity (i.e., level 3 in the CPT code set) compared with other general medicine physicians.

“These differences do not appear to be explained by patient complexity,” they added.

For the purposes of the study, high-severity billing codes included CPT code 99223 for initial hospital encounters, 99233 for subsequent encounters and 99239 for discharge encounters.

The number of hospitalists increased by 76% during the 10-year study period, while non-hospitalists decreased by 43.6%. The share of encounters performed by hospitalists rose significantly — from around 46% to more than 76% — for all three encounter types.

“The proportion of high-severity billing across the hospital, subsequent and discharge encounters was consistently higher among hospitalists relative to non-hospitalists across all years,” the researchers wrote.

“This gap is growing over time,” they added.

Key factors and takeaways

“The increase in the number of hospitalists over time may be contributing to rising national costs related to hospital care,” the researchers wrote.

They speculated that the difference in coding practices can be partially explained by instances in which primary care physicians (PCPs) admit their own patients to hospitals:

“In these situations, PCPs likely know their patients quite well and thus may be more efficient at writing their notes, reading their medical charts, examining and speaking with patients, and preparing their discharge paperwork. This could translate to less time spent for each encounter, which is a key component in the E/M criteria that determine the level of billing.”

The discrepancy also could arise if hospitalists are more likely to receive productivity bonuses, which may create a financial incentive to bill a greater number of RVUs.

“It is also possible that non-hospitalists, who spend much less time caring for patients in the hospital setting, may be under-coding for patient severity, which then results in the gap in billing,” the researchers wrote. “On the other hand, hospitalists may potentially devote more time and training to documentation practices that support higher-severity billing given that their entire source of billing revenue may come from treating hospitalized patients.”

In past comments, hospital-medicine advocates have noted that limiting inpatient coding to three levels can constrain options and leave high-severity codes as the most viable choice in many scenarios.

The researchers specifically called out discharge encounters lasting more than 30 minutes (CPT 99239), a code they said increased significantly for both hospitalists and non-hospitalists (but more so for hospitalists).

“Over the past decade, several national health reform efforts have increased the accountability of hospitals and their physicians for post-discharge care and outcomes,” the researchers wrote. “Inpatient physicians are thus seeing increased pressure from leadership to improve transitions of care. This may then translate into spending more time communicating with PCPs, providing patient or caregiver education and performing better medication reconciliation, all of which could account for the increase in higher-intensity billing for discharge encounters.”