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Methodology: How Hospital-Acquired Conditions Are Calculated

A quarter of the nation’s hospitals in October will receive lower Medicare payments because their rates of patient complications are higher than their peers. Federal officials released a preliminary analysis in April scoring hospitals and provisionally assigning penalties to 761 hospitals.

The Centers for Medicare & Medicaid Services assessed hospitals’ rates of infections in patients with catheters in major veins and their bladders as well as eight other patient injuries, including blood clots, bed sores and accidental falls. For each hospital in its analysis, Medicare calculated a preliminary “hospital acquired-condition” score from 1 to 10, with the higher number indicating that the hospital had a greater rate of patient harm.

In the government’s preliminary assessment, hospitals with a score above seven would be penalized. Medicare calculated scores for Maryland hospitals but did not assess penalties because that state has its own payment arrangement with Medicare and is exempt from this program.

Later this year, Medicare will release the final scores in this Hospital-Acquired Condition (HAC) Reduction Program. Hospitals getting the penalty, which was created by the federal health law, will lose 1 percent of each Medicare payment from Oct. 1 through Sept. 30, 2015.

The final scores may differ from the preliminary ones because Medicare will be looking at infections over two years, not one. The preliminary scores are based on infections during the 12-month period from July 2012 through June 2013. Final scores will include infections that occurred from the beginning of 2012 through the end of 2013. “It’s not out of the realm of possibility that some HAC scores change due to the longer data collection period for the infection measures,” said Eric Fontana, an analyst with The Advisory Board Company, which consults with hospitals.

In some cases, the hospital’s final score may change because it had too few cases during the initial 12-month period to estimate its infection rate, but the full two-year period provided enough cases for the government to make that calculation. The time period for a third measure, looking at serious complications for surgical patients, remains the same, including incidents from 2011 through June 2013.

The accompanying list includes the names of hospitals with preliminary scores of nine or higher, which experts say are most likely to be penalized. The preliminary scores for all hospitals can be downloaded as a spreadsheet file. Certain types of hospitals are exempted from the penalties, including critical access hospitals, specially designated cancer hospitals and those devoted to rehabilitation, children, long-term care and psychiatric treatment. Hospitals with too few cases for Medicare to evaluate are also exempted.

KHN asked Dr. Ashish Jha, a researcher at the Harvard School of Public Health, to analyze the preliminary penalties. Jha found that certain types of hospitals—including academic medical centers, those treating more poor patients and those in West and Northeast—were more likely to be assigned preliminary penalties. That stayed true even when Jha held other variables constant. The analysis included 3,203 hospitals. It omitted hospitals whose characteristics were not included in the American Hospital Association annual survey. The results of Jha’s analysis are here.

Below are the three measures Medicare is using to calculate the hospital-acquired conditions scores. Each measure counts a third except if a hospital is missing data or has too few incidents to be evaluated. Infection rates were adjusted by the type of hospital and complications were adjusted to take into account the differing levels of sickness of each hospital’s patients, their ages and other factors that might make them more or less fragile.

Central Line-Associated Bloodstream Infections (CLABSIs) occur when germs enter the bloodstreams of patients who had a flexible tube inserted into a large vein, usually in the neck or upper chest, to administer treatments such as nutritional fluids, chemotherapy, antibiotics or dialysis. The rates are based on all patients in intensive care units, including adult, pediatric, neonatal, Medicare and non-Medicare patients.  The data are collected by the Centers for Disease Control and Prevention through its National Healthcare Safety Network. If a hospital did not report its infection rates to the CDC, Medicare assigned it the highest score.

Catheter-Associated Urinary Tract Infections (CAUTIs) occur when bacteria or viruses enter the bladder, kidneys, urethra or ureters of someone who has had a thin tube placed in the bladder to drain urine. These rates are collected in the same manner as the central line infection rates, and Medicare is basing both preliminary and final scores on the same time periods as with the central line data.

Serious Complications measures how often Medicare patients experienced eight types of major but potentially preventable complications while in the hospital. Those are (1) a collapsed lung that results from medical treatment; (2) blood clots in the lung or a large vein after surgery; (3) a wound that splits open after surgery (4) accidental cuts and tears; (5) bed sores; (6) central-line related blood stream infections; (7) a broken hip from a fall after surgery; (8) a blood stream infection after surgery. Medicare calculates these rates from bills submitted by hospitals for the treatment of Medicare patients in its fee-for-service program, so the blood stream infection rate may differ from the CDC infection measures. Not included in the serious complication rates are patients insured in other ways and those with Medicare Advantage managed care plans.

Each year, Medicare will reassess hospitals and decide which should be penalized. While the amount of the penalty does not change, the criteria Medicare uses expands. In October 2015, Medicare will add rates of surgical site infections to its analysis, and in October 2016 it will include incident rates of two germs that are resistant to antibiotic treatments: Clostridium difficile, known as C. diff, and Methicillin-resistant Staphylococcus aureus, known as MRSA.

This article was produced by Kaiser Health News with support from The SCAN Foundation.

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