Showing posts with label Spin. Show all posts
Showing posts with label Spin. Show all posts

Tuesday, November 20, 2012

Duh? Postoperative complications lead to readmissions



God knows I’ve written more than my share of papers that the Nobel Prize Committee has rightfully chosen to ignore. I understand that academicians need to publish in order to keep their jobs. Writing a paper is hard work and I don’t really want to demean it.

A paper reports that complications of surgery are linked to increased rates of readmission, and this seems rather obvious to me. It got a lot of media attention, and comment is needed.

The study, published in the Journal of the American College of Surgeons, looked at the records of over 1400 patients who had general surgical operations and found that 163 (11.3) were readmitted within 30 days of discharge.

The authors make some good points such as readmissions were not related to age, race, sex, or certain co-morbidities such as diabetes, smoking status, COPD, ascites, hypertension, steroid use, unintentional preoperative weight loss, history of bleeding disorders or renal disease. Readmissions were significantly more apt to occur if patients had preoperative dyspnea, open wounds or disseminated cancer.

But the main findings that readmissions were due to complications and the more complications a patient had, the more likely he was to have been readmitted, are not exactly earth-shattering.

The press release and articles accompanying the paper’s publication were a little over the top.

Here are some quotes from a few of the many articles about this research:

From the American College of Surgeons website: Findings published in the Journal of the American College of Surgeons lead researchers to devise a patient safety plan to decrease complications for the benefit of patients and hospitals.

From a site called Redorbit: [The surgeon-author] reported that the results of this investigation provided a framework for his research team to develop a simple complication-prevention plan that minimizes the risk of surgical patients developing complications.  

No such plan is mentioned in the paper.

From Infection Control Today: This patient safety approach includes engaging the postoperative care team to start transition-of-care planning early—especially for high risk patients—to encourage early discharge from the hospital. This too is not specifically stated in the paper nor is it supported by the data. In fact, early discharge might result in more readmissions. Who knows?

Incidentally, the press release, in most cases printed verbatim by the medical news websites, was wrong about the data forming the basis of the study. It says, “Researchers conducting this retrospective study analyzed patient records from hospitals that were enrolled in the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP), which is the leading nationally validated, risk-adjusted, outcomes-based program to measure and improve the quality of care in private sector hospitals. Data from Emory University Hospital was merged with ACS NSQIP data to identify unplanned readmissions.” Not so. The paper included patients who were operated on only at Emory University Hospital.

Slight digression: Even if readmission rates were not increased by complications, I would be in favor of a plan to reduce them.

One of the reasons I am skeptical about a lot of things is that when you look into the details, you often find that the “spin” produced by stories about a research paper is not always matched by its content.

I’m not the only one. A French study on the PLoS One website in September found that the spin generated by press releases and abstracts is highly likely to influence news reports about the research and overstate its beneficial effects.

I've written before about the need to read the whole paper and not just the abstract. You must be cautious about what is written in the press release too.

Thursday, November 15, 2012

Moderate maternal alcohol use lowers children’s IQ (not)



A new study shows that children of mothers who drank as little as 1 to 6 units of alcohol per week had children whose IQs at age 8 were statistically significantly lower than those of children who mothers abstained.

This finding was widely reported by news media yesterday. Google “IQ alcohol” and you will find many articles which uncritically describe the findings of the study. As is the case in many such articles, quotes from the press release accompanying the paper’s publication appear to have been liberally used.

The major problem with this study is one that I’ve written about before. Results that are statistically significant may not necessarily be clinically significant.

The difference in IQ between the two groups of children was 1.8 points. Do you really think that an IQ difference of 1.8 is going to be a life-altering finding for a child? I don’t.

IQ tests are often unreliable and if taken more than once can yield different results. A difference of 1.8 points is well within the margin of error of such tests. One source I found states that the margin of error of the IQ test used in this study is a minimum of 5 points. The children in this study were 8 years old when they took the test.

The study, done by a group in Bristol, England, was published on PLoS One and the full text is available here. Caution is advised if you plan to read it. There are many other problems to consider.

Data collected for this paper were pulled from another study which was done from 1992 to 2000 about the genetics of alcohol metabolism. The primary focus of the original study was not the hypothesis of the IQ study.

A unit of alcohol was defined as 8 grams by the authors. Since I was not familiar with what 8 grams of alcohol really meant, I looked it up. A “standard drink” was said to contain anywhere from 8 (in the UK) to 14 grams (in the US) of alcohol.

Here’s a quote from the paper’s “Methods” section, “At approximately 18 and 32 weeks of pregnancy women were also asked on how days during the past month they had drank [sic] 2 pints of beer (or the equivalent amount of alcohol), any women who reported doing this on at least one occasion was classified as a binge drinker in our analysis of the association between genotype and binge drinking.”

Really? Two pints of beer on one occasion makes a woman a binge drinker? Depending on the type of beer, a pint contains 2 to 3 units or 16 to 24 grams of alcohol.

To help you understand the paper better, here is a table:


I asked my wife what she thought of this study and she said, “I think the women who drank were probably more fun to be with.”