This story delivers intriguing information about a study that corroborates a previously reported link between aspirin use and decreased incidence of cancers. It does a nice job in pointing out that the link does not necessarily mean there is a cause-and-effect relationship; however, that uncertainty is not appropriately reflected in the story’s own use of language. (The headline — “Aspirin may help ward off gastro cancers” — suggests a cause and effect relationship.) In addition, the story’s use of statistics will likely leave readers with an inflated sense of the possible benefits, and it missed describing one researcher’s financial ties to an aspirin maker — a potential conflict of interest.
The reason this matters is because colorectal cancer is the nation’s third leading cause of cancer: Some 93,090 cases of colon cancer and 39,610 cases of rectal cancer will likely be diagnosed this year, according to the American Cancer Society. An estimated 49,700 deaths are predicted from colorectal cancer in 2015.
If aspirin, a cheap, commonly used, readily available drug, can ward off one in five such cancers, that would be a big deal.
There was no mention of cost, but there did not need to be. Aspirin is widely known to be cheap. The story could have mentioned the savings we’d collectively reap (in terms of treatment costs) if aspirin truly does prevent colorectal cancer, and/or the cost of treating downstream complications such as bleeding. But we’ll rate this Not Applicable.
The second sentence of the story notes that “there was a 20 percent lower risk of cancers of the gastrointestinal tract, especially in the colon and rectum, among people taking aspirin.” We think that statistic is likely to give readers an inflated sense of the benefits. Instead, we wish the story had presented the absolute reduction in risk for people taking aspirin vs. not. In other words, what was the rate of cancer in the aspirin group and what was the rate of cancer in the no-aspirin group? That would help readers understand if this is a very meaningful reduction, or if the 20% reduction is merely making an already-low risk even lower.
The story notes prominently the possible harms: “While not common, aspirin can cause serious, even occasionally fatal, stomach bleeding, even at low doses, he said.”
The story notes that the data supporting its lede are drawn from large, long-term studies, and that the findings, presented at a conference, “should be viewed as preliminary until published in a peer-reviewed journal.”
The story also wins kudos for being explicit about the difference between association and causation: “And the study only showed an association between aspirin use and gastrointestinal cancer risk, not a cause-and-effect relationship.” Although that caveat ideally could have been presented higher up in the story.
But the story’s headline and opening sentence are likely to confuse readers about the reported relationship. If the study can’t prove a cause-and-effect relationship between aspirin and cancer, it’s misleading to claim that aspirin “may help ward off” and “prevent” cancer. Those active verbs certainly imply that aspirin “causes” a reduction in cancer.
We’re on the fence with this one, but we’ll give the benefit of the doubt here, with suggestions for improvement noted for next time.
The story suggests that colorectal cancer is one of the two “leading causes of sickness and death in the U.S. and much of the world.” However, it never supports that statement with figures on the prevalence or incidence of these cancers, or an individual’s lifetime risk. Such figures are easily obtainable from the American Cancer Society.
The story includes an independent source from the American Cancer Society. But it makes no mention of possible conflicts of interest, even though they would not have been hard to find: The American Association for Cancer Research news release notes that Yin’s team includes Andrew Chan of Harvard Medical School, “who has previously served as a consultant for Bayer Healthcare [which makes aspirin], Pfizer Inc., and Pozen Inc.”
The story does not say what other interventions have been shown or are under investigation to reduce the incidence of colorectal cancer. They include colonoscopy/polyp removal, increased activity, weight loss, cessation of cigarette smoking, and cutting back on excessive alcohol use.
No explicit mention is made of aspirin’s availability, but the drug is widely known to be commonly available, and the story certainly conveys that impression.
The story notes that the study is the latest in a long line of studies that have reached similar conclusions. And for that reason, we would love for this story to have focused on aspirin and cancer risk more broadly.
The story rates a Satisfactory because it clearly went beyond both the American Association of Cancer Research news release and this news release from the Harvard School of Public Health. However, it’s equally clear that these news releases and the conference presentation were the primary basis for the story. As noted above under the Novelty criterion, we think a story that provided a broader, more inclusive view of the evidence would been more useful to readers.