Data Interpretation

The Los Angeles Times has long article on the recent abortion-breast cancer workshop held by the National Cancer Institute. (Their link requires registration.)

Now, pay attention here. Those people who claim that there is NO abortion-breast cancer link largely base their certitude on what is known as the Melbye study. The Melbye study was published in 1997.

That study used a large database from Denmark. In Denmark, every man, woman and child has a medical number, and every single medical event experienced by that individual can be accessed through those numbers. Thus, the study does NOT rely on people telling you the truth about whether they had an abortion. These kinds of studies are called record-based.

In the Los Angeles Times article, the reporter tells us about only one objection that some researchers have made to the validity of the Melbye study.

As the LA Times reporter writes" One problem: The abortion date only went back to 1973, and considering how long it can take for breast cancer to appear, the study may have missed women who hadn't yet developed breast cancer but might later on."

Doesn't that sound like a rather weak and strained objection to the Melbye study?

Now, here's what researchers have actually said, when they challenge the conclusion of the Melbye study:

"This study has been severely criticized for its misclassification and data adjustment errors. For example, the researchers followed non-abortive women more than twice as long as the women who did have elective abortions. They compared a smaller group of younger women (280,691) who had had abortions to a far larger number of older women (1,248,541) who hadn't procured abortions. The difficulty with this practice is obvious. Women who live longer have a greater chance of developing breast cancer."

That's a much stronger objection. Too bad it didn't make it into the Los Angeles Times.