Two hospital safety reports issued last month drew another confused picture of the inpatient experience.

The Centers for Disease Control and Prevention (CDC) concluded that the number of infections U.S. residents acquire during hospital stays has declined substantially over the last decade, for two notable reasons: Hospitals have tried to improve their practices, and nursing homes have admitted more patients for medical care.

Consumer Reports concluded that hospitals vary widely on safety measures and in how likely patients are to die of avoidable surgical complications. The organization said that patients are at higher risk in some hospitals of national renown than in some tiny facilities in rural areas.

The CDC report, as interpreted by the New York Times, shows that there were about 722,000 hospital infections in 2011; previous reports put that estimate at about 1.7 million a year. So in 2011, 1 in 25 patients contracted an infection while in the hospital, versus 1 in 20 previously.

Federal officials said that the old estimate, issued in 2007 using data from 2002, was less precise.

According to The Times, the new report, published in the New England Journal of Medicine, is the first nationally representative count of hospital infections. Its researchers randomly selected more than 10,000 patients at 183 hospitals.

Health officials say that the old and new estimates, despite not being precisely comparable, give an indication of the trajectory of hospital infections, which kill thousands of people every year.

Approximately 75,000 people with infections died in 2011 for a ratio of about 1 in 9, which CDC officials called “a trend toward improvement.” That’s a hedged description due to the fact that although hospitals were key to the declining numbers, other forces were at work, as noted by The Times: More than 6 in 10 operations are performed outside of hospitals in outpatient facilities such as orthopedic surgery centers, and much of the continuing care that used to be provided by hospitals is shifting to nursing homes. To put it bluntly, there are fewer opportunities for hospitals to mess up.

The CDC report counted only hospitals’ rate of infections, but the feds said they were working to expand data collection to include nursing homes and outpatient facilities.

The Consumer Reports story was the result of crunching the safety rating numbers of 2,591 hospitals.

In its coverage of the report, Reuters described the rate of U.S. hospital errors as “soaring.” It alluded to the 1999 Institute of Medicine (IOM) report that first shone a light on the problem of hospital errors, concluding that at least 98,000 people died annually from medical mistakes in hospitals. In 2010, the Department of Health and Human Services (HHS) said poor hospital care contributed to 180,000 deaths of Medicare patients every year. A 2013 study said at least 210,000 died and maybe as many as 440,000 every year. Last month, in “Hospital Errors Remain Too Common Because of Doctor Deficiencies,” we, too, revisited the apparently intractable problem.

Reuters said that if the high numbers in the 2013 study were accurate, poor hospital care would be the country’s third leading cause of death, after heart disease and cancer.

Consumer Reports analyzed data on readmissions to hospitals within 30 days of discharge. Such quick turnarounds often signal poor initial care or follow-up; overuse of CT scans (which can cause cancer years later); hospital-acquired infections; miscommunication about things like discharge instructions; and mortality.

The mortality statistics concerned patients who had a heart attack, heart failure or pneumonia and died within 30 days of entering the hospital. They also accounted for surgery-related deaths, meaning patients who had treatable but ultimately fatal complications after an operation, such as blood clots, or cardiac arrest.

In past reports, some hospitals rightfully objected if their numbers were high because their patient populations were sicker when they were admitted. This time, according to Reuters, Consumer Reports adjusted for that.

See how Consumer Reports rates individual hospitals by linking here, but it requires a subscription to the magazine.

Patients who are hospitalized for pneumonia at low-scoring facilities were 67% more likely to die within 30 days of admission than pneumonia patients at top-scoring hospitals. Of 1,000 surgical patients who develop a serious surgical complication in top-rated hospitals, 87 or fewer die; more than 132 die in low-rated hospital.

According to Reuters, consumers might be frustrated if they research their local hospital on both Consumer Reports and Medicare’s Hospital Compare because many kinds of data are missing from many hospitals.

And in some cases, the two raters flat-out disagree. Consumer Reports gave one hospital in Nyack, N.Y., a safety score of 25, tied for ninth worst. But Medicare rated its surgical complications at about average, as well as readmission and death rates for pneumonia, heart attack, and heart failure patients.

Ditto for higher-rated hospitals. One that got the highest safety rating by Consumer Reports had rates of surgical complications, infections, death from pneumonia and heart failure, and readmission of heart failure and pneumonia patients no different from the national average, according to Medicare. But it did very well in avoiding unnecessary imaging.

This is a consider-the-source issue. Medicare might deem a hospital’s infection or mortality rate “average” if it’s only a few percentage points below the U.S. average, but Consumer Report sees it as below average.

We’ve covered the rocky terrain of hospital ratings many times – here and here, for example. The bottom line is that consumers should understand the biases of the raters, the demographics of the facilities and look for trends as much as single issues or categories of care.