In a race for incomplete news coverage, news about a study in the journal Menopause, “Moderate alcohol intake lowers biochemical markers of bone turnover in postmenopausal women,” may outpace news from earlier in the week from a BMJ paper about alcohol and arthritis – both in volume and in missing key caveats.
This was a tiny, short-term study in just 40 women. Yet look at how definitive are the statements in this sampling of headlines:
Perhaps even more important, one important caveat was missed by almost all stories. The TIME.com story was an exception:
Although there is substantial evidence that moderate alcohol consumption correlates with higher bone mass density in postmenopausal women, it is much less clear whether consuming alcohol lowers the fracture rate, the authors note. Therefore, even if drinking had no detrimental effects, it would be unwise to recommend drinking for the purpose of preventing fractures.
Earlier the story was careful to explain:
Researchers tracked certain blood markers of bone health throughout, and found that these markers of bone density correlated positively with alcohol consumption: in other words, the more the women drank within the moderate range, the better their bone health looked.
I’ve added the emphasis in red to point out that – in other words – this study looked at only a surrogate marker. Should women care about a blood marker? Or should they care about real outcomes like fractures? This study didn’t show anything about the latter. That doesn’t make it unimportant. It is intriguing research. But the news coverage usually failed to point out this important limitation. Stories overstated and oversold.
Maybe journalists were swayed by the researchers’ comments: “The results presented here have a clear message for public health as well as for practicing clinicians advising and managing patients at risk of osteoporosis.” Seems a little over the top given the limitations we’ve highlighted.
Journalists and consumers should read our little primer, “Surrogate markers may not tell the whole story.” Journalists need to ask themselves: What was the outcome being studied? What was the endpoint? In how many people? For how long? What can we say and what can’t we say about the significance of this?
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