Those who think “more testing is better medicine” needs to become better versed in the dangers of false positives:
Many of the scans yield false-positive results, which lead to unnecessary (and risky) treatments. Even recommended tests yield a scary number of false readings. Take mammograms, an often promoted routine exam. According to research compiled by the U.S. Agency for Healthcare Research and Quality:* The percentage of false-positive readings is between 7 percent and 8 percent for women aged 40 to 59 who took the test.
* That figure drops to around 4 percent for women 60 to 79, mainly because the chances of getting breast cancer rise the older women get.
* If every woman between 40 and 59 in the United States had a mammogram, a few million would be fretting unnecessarily over a wrong result.
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“If every woman between 40 and 59 in the United States had a mammogram, a few million would be fretting unnecessarily over a wrong result”.
When there’s any doubt about a specific reading, the patient is called back to the facility for a repeat exam.
Each woman now signs a consent form allowing the facility ( in Boston area ) to leave a message on her machine telling her to return to the clinic for a repeat. Past failure to have this form of notification for an abnormal reading resulted in a lawsuit by the husband of the woman, to whom the phone message was directed.
As you probably know, it’s extremely important that the patient have her yearly mammogram at the same facility each year and that all records be housed ( if at all possible) at that same facility.
I’ve yet to see a calm woman before or immediately after a mammogram. It’s something all women have to endure, whether they’re healthy or not.
If breast cancer runs in a family, women are encourage to begin mammography at age 25.
“The percentage of false-positive readings is between 7 percent and 8 percent for women aged 40 to 59 who took the test.”
What is omitted in this sentence is that this is the risk after a single mammogram. The cumulative risk of at least one false positive after 10 yearly mammograms in the US is close to 50% (this takes into the consideration that false positive rate is lower on subsequent mammograms; if you just take 7-8% after each and do the math the number will be higher). About a forth of false positives end in biopsy. There is also a risk of overdiagnosis and overtreatment.
” It’s something all women have to endure, whether they’re healthy or not.”
Screening is a choice. It is not an obbligation or something “everyone must do”. Women have a right to consider if a small (in absolute numbers) chance of having their life prolonged is worth the chance of getting unnecessary treatment for an early cancer that they may never know they have if it remained undetected, as well as this large risk of false positives.
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