RT Journal
A1 Layde PM
T1 Smoking and cervical cancer: Cause or coincidence-reply
JF JAMA
JO JAMA
YR 1989
FD September 22
VO 262
IS 12
SP 1632
OP 1632
DO 10.1001/jama.1989.03430120081022
UL http://dx.doi.org/10.1001/jama.1989.03430120081022
AB In Reply.— 
    Although cigarette smoking may well make a causal contribution to cervical carcinogenesis, Dr Winkelstein overstates the case with his implication that the association of sexual activity with cervical cancer is as likely to be due to confounding as the association of smoking with cervical cancer. The preponderance of evidence from many studies indicates that the major etiologic factor for cervical carcinogenesis is a sexually transmitted agent.1 For example, cervical cancer in virgins is very rare,1,2 while it is not at all uncommon in nonsmokers who have multiple sexual partners. In addition, for the reasons stated in my editorial, I believe sexual activity is a particularly poor surrogate of the likelihood of infection with the sexually transmitted agent of cervical cancer. This both lowers the apparent relative risk (or odds ratio) for the association of sexual activity and cervical cancer and also severely impairs the ability to