The strengths of this story include a good overview of the study design that helps readers understand how the new information contributes to our understanding of the effects of mammography. It is also one of the few stories to list the funders of the study. On the other hand, it failed to mention any of the harms of screening and it gave readers only cursory comments from independent sources.
Millions of women undergo mammography each year based on what they are told about its potential benefits. This story plainly states the results of a study that concludes those benefits appear to be smaller than generally believed. But this story offers less than some other reports in the way of perspectives that would help readers make use of the results in their personal decision-making.
The story does not mention the costs of screening or follow-up testing or treatment – and those costs can be significant to the individual and are significant, collectively, to society.
This story features an accurate description of what the researchers reported: that mammography offers modest benefits that appear to be smaller than previously believed. It not only referred to the relative reduction in breast cancer deaths, but also reported the calculation that 2,500 women would have to be screened every other year for a decade in order to prevent one additional breast cancer death.
However, the story is rated as Unsatisfactory because of an error in a description of the study results. The story says that women who were screened had a 10 percent lower rate of breast cancer death, with only a third of that reduction due to mammography. Actually, the researchers said the women who were screened had a 28 percent reduction in breast cancer death, while women who were not screened had an 18 percent reduction in breast cancer death, thus leading to the conclusion that screening could account for the 10 percent difference, which is a third of the reduction seen among women who were screened.
This story does not discuss harms related to screening, which include false alarms, but also treating women when their tumors would not have becoming life-threatening.
This story does a good job of briefly describing the main strength of the study design: that it allowed for a comparison of the effects of improved treatment with the effects of offering mammography screening. The story also mentions one criticism of the study: that it may not have lasted long enough to capture the full benefit of screening.
However, the story could have more clearly pointed out that this study was observational and that unlike a randomized trial it cannot prove that changes in breast cancer death rates were caused by screening and treatment, only that the changes happened at the same time that screening and treatment were changing in Norway.
The story does not exaggerate the risk of breast cancer or the need to be screened for it.
This story is one of the few that told readers that the study was funded by the Cancer Registry of Norway and the Research Council of Norway. It also includes a quote from an independent source and cites a statement released from the American Cancer Society.
As with much of the other coverage of this mammography study, this story does not explain the alternatives. Other stories included some discussion of a woman’s ability to make a choice about whether to be screened. This story didn’t explicitly acknowledge that option.
The availability of mammography is not at issue. This story would have been better if it pointed out that while Norway built a system connecting mammography screening with multidisciplinary treatment teams, that sort of follow-up support may not be available to all women who get mammography screening in the United States.
While mammography is not new, this story clearly explains what is different about this study and how it offers a new perspective on mammography and breast cancer treatment.
The story does not appear to rely on a news release.