After a study found no link between U.S. hospitals that get accredited by independent organizations — including the Joint Commission — and lower death rates, the Joint Commission responded that the study has methodological issues that bias it against accredited hospitals.
The study authors looked at 30-day mortality and readmission rates for selected medical and surgical conditions among Medicare inpatients using billing data.
They compared two significantly different groups of hospitals: state-surveyed hospitals — 93 percent with fewer than 100 beds — and Joint Commission-accredited hospitals that are often larger, as 66 percent have over 100 beds, the accrediting organization said.
Major teaching hospitals made up 216 of the Joint Commission-accredited hospitals in the study, but none in the state-surveyed group. Only four state-surveyed hospitals had 400 beds or more, compared to 403 Joint Commission-accredited hospitals.
"It is not possible to make valid comparisons when the two groups are so radically different," the Joint Commission said.
To assess outcomes, the study looked at six common surgical procedures, but four of the six procedures are rarely performed in hospitals with fewer than 100 beds, according to the Joint Commission.
Additionally, in studies that look at mortality risks after hospitalization, measuring the severity of the illness that led to admission is the strongest predictor of a patient's risk of death, but this research did not include these measures, the Joint Commission said.
"Despite this study's methodology and conclusions, the data actually showed that for patients with the medical conditions cited, Joint Commission-accredited hospitals demonstrated lower mortality than state-surveyed hospitals, at conventional levels of statistical significance," the accrediting organization said.