One medical malpractice insurer, The Doctors Company, has an interesting article on medical malpractice claims concerning pap smears.
Here is a excerpt from the article that discusses the scope of the problem:
To put the potential magnitude of this problem in perspective, a College of American Pathologists (CAP) study of the five-year “look-back” at previous negative Pap smears following the diagnosis of HSIL/carcinoma found that 10 percent of prior smears were false negatives for SIL/carcinoma. If atypical squamous cells of undetermined significance (ASC-US) were included, 20 percent of prior smears were false negatives. In 1996, the American Cancer Society predicted 15,700 new cases of cervical cancer and 4,700 deaths. Published studies indicated that 60–75 percent of women dying from cervical cancer either never had a Pap smear or had not had one in the five years prior to diagnosis. Therefore, if one assumed that 40 percent of the predicted new cases of cervical carcinoma had a single Pap smear in the prior five years with a 20 percent false-negative rate, there was a potential for 1,256 new claims for failure to diagnose cervical carcinoma on a Pap smear in 1996 alone! [Footnotes omitted.]
The cause of the errors is split between sampling errors and interpretation errors.
And what is one method that the insurance company recommends to its insureds to "help" patients? Put in the path report that errors are made. This is also known as the "give the defense lawyer something to use for closing argument" recommendation. ("You can’t expect us to get every one right. We told you that we get them wrong.")
Include a “statement” in the Pap smear report reminding the clinician (and patient) that the Pap smear is a screening test with an irreducible false-negative rate, the consequences of which can be minimized by obtaining an annual Pap smear. It is important to educate the public, primary care physicians, and gynecologists about the limitations of the Pap smear so that they have realistic expectations about its sensitivity and understand why it is important to obtain a Pap smear annually.
And what about this little goodie:
A single Pap test has a high false-negative rate (circa 55 percent). Therefore, when collecting the Pap test specimen, if the clinician sees a cervical abnormality (ulceration, induration, a visible or elevated lesion, bleeding), it should be biopsied. In a patient with cervical cancer and a false-negative Pap test, the failure to biopsy a cervical abnormality may be below the standard of practice and constitute negligence.
There is so much more here. Read it and educate yourself before accepting one of these cases.