Can You Trust the Information You Read on MidwifeInsight?
How good is the information that you see on this webpage? For that matter, how good is the information that you get on any webpage, or in the media in general? Most of the articles on the MidwifeInsight website and the “medical news” that you see on Nancy’s Blog are extracted from news articles, in sources that I scan and that, for some reason, I trust. However, before posting them, I always refer back to the original journal articles on which they are based, and then search the professional literature for more articles on the same subject. I include links to these sources in my posts. So then, how much can we trust these sources, these journal articles describing research studies and their results? We all know about the bias in research, most blatantly where studies showing “positive” results, that is, the results that the researchers want to show, are published much more frequently than “negative” studies that refute the hypothesis being tested. This bias is particularly evident in studies from pharmaceutical companies, but is certainly not limited to them. It comes into play throughout healthcare, particularly where billions of dollars come into the mix, which they do in the case of, for example, nutritional supplements.
Most of us, including most healthcare providers, do not really understand how to read or analyze a research article, what type of study it describes (basic research trial, applied research, replication, cohort study, meta-analysis, etc), how to know if the authors asked the right question, used the correct study design and methodology for a particular topic, had sufficient numbers of subjects to arrive at a meaningful (“statistically significant”) conclusion, considered all the variables including confounding ones, and so forth. In truth, many of us who do read professional journal articles stick to the abstract or summary and the conclusions, skipping all those confusing and messy sections devoted to a description of exactly how the study was done. I heard on NPR’s “All Things Considered” last night that most medical students and practicing physicians get a lot of their information from Wikipedia! I love Wikipedia, and I get a lot of information there myself, but not about midwifery. I have read their page on midwifery and noted a number of inaccuracies – have even corrected a few blatant ones myself. Anyone can write or edit for Wikipedia – within certain guidelines and subject to review by the editors. I assume that if I can find bad information on the Wikipedia midwifery page, there is probably bad information throughout the website. Then there is Medscape, which summarizes the literature on many medical subjects and dumbs it down to some extent. (Today’s top story – “Eating low-fat yogurt cuts risk of Type II diabetes!”) Ultimately, there is PubMed, which has original articles from many journals, reprinted exactly as written. The internet has, in fact, made it completely unnecessary to go to a medical school library to research most medical topics.
But if we take shortcuts in how we arrive at conclusions about our health, can we trust those conclusions?
Ben Goldacre, who writes a great column for The Guardian called “Bad Science,” says that “journalists can mislead the public about the answers of evidence-based medicine, which is bad. But they also mislead us on the methods and techniques We live in a new era of doctors and patients – at our best – making decisions together. For that collaboration to work, everyone needs to understand how we know if something is good for us, or bad for us. The basics of evidence-based medicine, of trials, meta-analyses, cohort studies and the like should be taught in schools and waiting rooms. It’s interesting, but it’s also life and death: people care about it..”
Well, it’s interesting to Ben Goldacre, because he is a science nerd and a stats geek. (According to Wikipedia, Benjamin Michael Goldacre, MRCPsych is a British physician, academic and science writer. As of 2012 he is a Wellcome research fellow in epidemiology at the London School of Hygiene and Tropical Medicine.) He has written two books on Bad Science and Bad Pharma. Personally, I get my thrills elsewhere. But he’s right, it is life and death for the rest of us. We need to pay thoughtful attention to what we read, especially if we are considering acting on the information.
A Particular Case In Point – Do Vitamin Supplements Help Us To Live Longer?
This morning I thought about doing a little online research about vitamins. I have been reading in the media that vitamin supplements may actually have a negative effect on longevity – that is, taking vitamins may shorten your life span. This is interesting, and evidently there is good research out there substantiating this claim, so I set out to find it. I googled “vitamins and overall mortality.” The first article to attract my attention wass “Vitamins and Mortality” by Steven Novella on a site called “Science-Based Medicine.” He offered a reasoned commentary on vitamin use and abuse by Americans who have a “deeply-embedded cultural belief” that vitamins are good for them, and the more the better. Then Novella turned to the literature on vitamins and longevity, particularly an article that went viral in the popular media by finding “a small but statistically significant increase in mortality for those taking multivitamins, B6, folic acid, iron, copper, magnesium and zinc. There was also a small decrease in mortality for those taking calcium.” Novella concluded that “it is … not possible from this study to draw any conclusions about cause and effect – that vitamin use increases mortality. But it does provide a cautionary reminder that it is not reasonable to assume that vitamin supplementation is without any risk. We still need to follow the evidence for the use of specific vitamins at specific doses for specific conditions and outcomes.”
Good start. Then I checked Medscape, which has an article stating, “In women aged 55 to 69 years, several widely used dietary vitamin and mineral supplements, especially supplemental iron, may be associated with increased risk for death, according to new findings from the Iowa Women’s Health Study.” A link there took me to this study, Dietary Supplements and Mortality Rate in Older Women: The Iowa Women’s Health Study, published online by JAMAevidence.com. I read the abstract and then scrolled down through the study. It is lengthy, and includes a number of tables in such a miniscule font that they are illegible (I know, I can click on them one by one and enlarge them – arduous and not so thrilling). The summary in the abstract states that, “in older women, several commonly used dietary vitamin and mineral supplements may be associated with increased total mortality risk; this association is strongest with supplemental iron. In contrast to the findings of many studies, calcium is associated with decreased risk.” There you see, “in contrast to the findings of many studies….” From an ethical point of view, was I bound to look for these studies next? I was getting weary of this and suspecting that it might be a frustrating topic for me to pursue and report on. I went back to the Google search list and scrolled down. I found a January 2013 study by Stephen Daniells entitled “Multivitamins Don’t Increase Mortality Risk: New Meta-Analysis.” My local GNC and Vitamin Shoppe will be very happy to see this one! But wait – it was published in an online newsletter called “Breaking News on Supplements & Nutrition,” obviously supported by the supplement and nutrition industries. Could I trust that? Should I even bother to read it? I thought not.
Conclusions and Recommendations (Just Like a Real Research Article!)
Bottom line – there is no bottom line! There are good studies on vitamins and longevity and on everything else in healthcare, peer-reviewed and published in reputable journals, and there are crappy studies and pseudo-studies on the same things, thrown together and published online by special interest groups. As consumers, we need to understand where our information is coming from and how to use it, or we risk falling for false and exaggerated claims for nostrums, gadgets, regimens, and other quackery that are no more useful than snake oil, and may be worse. Remember too that some truly valuable information is not out there at all – it’s been withheld because publishing it may hurt someone’s bottom line.
To see a wonderful 14-minute TED Talk by Dr. Goldacre, go to http://www.ted.com/talks/ben_goldacre_battling_bad_science.html.