Sociodemographic Characteristics and Screening Outcomes of Women Preferring Self-Sampling in the Dutch Cervical Cancer Screening Programme: A Population-Based Study

Abstract

Background: In the Netherlands, lower high-risk human papillomavirus (hrHPV) positivity but higher cervical intraepithelial neoplasia (CIN) 2+ detection were found in self-collected compared with clinician-collected samples. To investigate the possible reason for these differences, we compared sociodemographic and screening characteristics of women and related these to screening outcomes.

Methods: We extracted data from PALGA on all primary hrHPV screens and associated follow-up tests for 857,866 screened women, invited in 2017 and 2018. We linked these data with sociodemographic data from Statistics Netherlands. Logistic regression was performed for hrHPV positivity and CIN 2+/3+ detection.

Results: Out of the 857,866 women, 6.8% chose to use a self-sampling device. A higher proportion of self-sampling users was ages 30 to 35 years, was not previously screened, was living in a one-person household, or was the breadwinner in the household. After adjustment for these factors self-sampling had lower hrHPV positivity (aOR, 0.65; 95% CI, 0.63-0.68)) as compared with clinician-collected sampling, as well as lower odds of CIN 2+ (aOR, 0.76; 95% CI, 0.70-0.82) and CIN 3+ (aOR, 0.86; 95% CI, 0.78-0.95) detection.

Conclusions: It is likely that the observed differences between the two sampling methods are not only related to sociodemographic differences, but related to differences in screening test accuracy and/or background risk.

Impact: Self-sampling can be used for targeting underscreened women, as a more convenient screening tool. Further investigation is required to evaluate how to implement self-sampling, when it is used as a primary instrument in routine screening. See related commentary by Arbyn et al., p. 159.

Figure 1.

Referral algorithm for the Dutch primary hrHPV cervical cancer screening programme. hrHPV, high-risk human papillomavirus; NILM, negative for intraepithelial lesion or malignancy; ASC-US+, atypical squamous cells of undetermined significance or higher.

Figure 2.

Outcomes following screening in the Dutch cervical cancer screening programme, cohorts 2017 and 2018 up until March 31, 2019. Cases with missing values for income or screening region are not shown. Approximately 1.5% of CIN 2+/3+ lesions were diagnosed outside of the normal screening pathways (i.e., either after incongruent advice or inadequate cytology). These are not shown on this flowchart but are included in the model. Imputed CIN values for women who used the self-sampling test and had no cytology result are not included. #, There were 56 women given the advice to return to routine screening following a hrHPV+/NILM screening result. Compliance with 6 month cytology is calculated as a proportion of those women receive advice to return for 6 month cytology. *, There were 19 women who used self-sampling given the advice for a repeat cytology test following an hrHPV+/ASC-US screening result. Compliance with referral is calculated as a proportion of those women receive referral advice. **, There were 142 women who received an advice other than referral for colposcopy following a low-grade cytology abnormality. Compliance with referral is calculated as a proportion of those women receive referral advice. ‡, Not all women who complied with referral advice received an histologically confirmed diagnoses (i.e., cytology only). These women are also included in this category. NILM, negative for intraepithelial lesion or malignancy; ASC-US+, atypical squamous cells of undetermined significance or higher.

Figure 3.

A–C, Proportion of women who used self-sampling within each category, sociodemographic characteristics, and screening history. (A) People in the household, socioeconomic status, and position in the household. (B) Age, and migration background. (C) Screening history, screening region, and income percentile. The orange line denotes the overall proportion of women who used self-sampling across all participants (6.8%). Women are counted once for each variable, that is, the same woman will appear in her respective age, screening history, and sociodemographic variable category. The total in each variable is 857,866 women.