Factors affecting the detection rate of human papillomavirus.

BACKGROUND

Maximizing the accuracy of human papillomavirus (HPV) detection from a single sample is important for clinical and research purposes. The purpose of this study was to determine whether cyclic hormonal variation, recent sexual intercourse, interval between samplings, and the technique used to sample affect the detection of HPV.

METHODS

This study was a prospective, longitudinal, randomized controlled trial. Three techniques for self-sampling (2 consecutive synthetic polyester fiber [Dacron] swabs, a single Dacron swab, and a tampon) were repeated at 3 different sampling times during a period of 4 to 6 weeks in addition to 1 clinician-directed sampling of the ectocervix and endocervix at the first sampling time. All self-samplings were taken in a proscribed randomized order. Women (aged 18 to 68 years) attending a colposcopy clinic for abnormal cytology or abnormal cervical appearance participated in the study. The outcome measure was the detection of HPV by polymerase chain reaction amplification.

RESULTS

The 103 participants provided 1,189 cervicovaginal samplings. Logistic regression indicated that intercourse within 48 hours of sampling did not result in a greater detection of high-risk or any HPV type (odds ratio [OR] = 1.05, 95% confidence interval [CI], 0.65-1.69; OR = 1.08, 95% CI, 0.73-1.60, respectively). Among those women who have regular menstrual cycles, there was no cyclic effect on HPV detection for high-risk and any HPV types. Time from previous sampling did not affect HPV detection. Among the self-sampling techniques, using a single self-swab and the tampon resulted in the detection of HPV between 10% and 35% less often than using 2 consecutive swabs (P < .025). Self-sampling with 2 swabs was not significantly different from clinician sampling for detecting high-risk HPV types (OR for self-sampling = 0.87 (95% CI, 0.66-1.13)).

CONCLUSIONS

HPV detection is not dependent on menstrual cycle timings, the recency of intercourse, or the time between samplings, but it is dependent on the sampling technique.