A comparison of the Papanicolaou smear and the cervigram: sensitivity, specificity, and cost analysis

A total of 3271 gynecology patients between the ages of 18-50 years were screened for cervical intraepithelial neoplasia and invasive cervical cancer by simultaneous Papanicolaou smears and cervigram, a noninvasive photographic method recently introduced for screening. The accuracy of each screening test, when positive or suspicious, was evaluated independently and the results compared with colposcopically directed biopsy results. The cervigram was significantly more sensitive than the Papanicolaou smear (P less than .001), whereas the Papanicolaou smear was significantly more specific than the cervigram in detecting cervical intraepithelial neoplasia (P less than .001). Cost analysis integrating sensitivity and specificity with cost per procedure indicated a greater yield of cervical intraepithelial neoplasia with the cervigram than with the Papanicolaou smear, by 3.7:1 case per dollar.