A 9-Year Follow-up Study of Participants and Nonparticipants in Sigmoidoscopy Screening: Importance of Self-Selection

Abstract

Background: Self-selection may compromise cost-effectiveness of screening programs. We hypothesized that nonparticipants have generally higher morbidity and mortality than participants. Methods: A Swedish population-based random sample of 1,986 subjects ages 59 to 61 years was invited to sigmoidoscopy screening and followed up for 9 years by means of multiple record linkages to health and population registers. Gender-adjusted cancer incidence rate ratio (IRR) and overall and disease group-specific and mortality rate ratio (MRR) with 95% confidence intervals (95% CI) were estimated for nonparticipants relative to participants. Cancer and mortality rates were also estimated relative to the age-matched, gendermatched, and calendar period-matched Swedish population using standardized incidence ratios and standardized mortality ratios. Results: Thirty-nine percent participated. The incidence of colorectal cancer (IRR, 2.2; 95% CI, 0.8-5.9), other gastrointestinal cancer (IRR, 2.7; 95% CI, 0.6-

Population Based Cancer Screening Programmes as a Teachable Moment for Primary Prevention Interventions. A Review of the Literature

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Acceptability and side-effects of colonoscopy and sigmoidoscopy in a screening setting

“…Comparing hospitalization rates among FS and TC screening attenders with the rates in the general population would lead to biased results, as screening attenders are likely to be healthier. 12,13 …”

Ethical issues with colorectal cancer screening—a systematic review

“…There is considerable variation in CRC screening by sociodemographic characteristics, by information provided, by the provider's understanding of patient's social context, and also by different world view, eg, fatalism (the view that all events are subject to fate or are inevitable) . Moreover, high‐risk groups may have lower participation rates . All such circumstances may result in selection bias in outcome studies.…”