A 9-year follow-up study of participants and nonparticipants in sigmoidoscopy screening: importance of self-selection.
Cancer Epidemiol Biomarkers Prev
; 17(5): 1163-8, 2008 May.
Article
em En
| MEDLINE
| ID: mdl-18483338
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, gender-matched, 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, 0.6-12.8), lung cancer (IRR, 2.2; 95% CI, 0.8-5.9), and smoking-related cancer overall (IRR, 1.4; 95% CI, 0.7-2.5) tended to be increased among nonparticipants relative to participants. Standardized incidence ratios for most of the studied cancers tended to be >1.0 among nonparticipants and <1.0 among participants. Mortality from all causes (MRR, 2.4; 95% CI, 1.7-3.4), neoplastic diseases (MRR, 1.9; 95% CI, 1.1-3.5), gastrointestinal cancer (MRR, 4.7; 95% CI, 1.1-20.7), and circulatory diseases (MRR, 2.3; 95% CI, 1.2-4.2) was significantly higher among nonparticipants than among participants. Standardized mortality ratio for the studied outcomes tended to be increased among nonparticipants and was generally decreased among participants.CONCLUSION:
Individuals who might benefit most from screening are overrepresented among nonparticipants. This self-selection may attenuate the cost-effectiveness of screening programs on a population level.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Neoplasias Colorretais
/
Comportamentos Relacionados com a Saúde
/
Sigmoidoscopia
Tipo de estudo:
Diagnostic_studies
/
Incidence_studies
/
Observational_studies
/
Prognostic_studies
/
Risk_factors_studies
/
Screening_studies
Limite:
Female
/
Humans
/
Male
/
Middle aged
País como assunto:
Europa
Idioma:
En
Ano de publicação:
2008
Tipo de documento:
Article