Abstract
Background. Colorectal carcinoma is the third most common malignancy worldwide, with a rapidly rising burden in Southeast Asia, whereas organized screening coverage in Indonesia remains highly limited and most cases are diagnosed at an advanced stage. Fecal occult blood testing is the most feasible first-line screening modality in resource-limited primary care settings; however, community-level data on the prevalence of positive results from eastern Indonesia are virtually non-existent.
Objective. To determine the prevalence of positive fecal occult blood test results in a community-based colorectal carcinoma screening program in the catchment area of Tomoni Primary Health Center and to analyze its association with age, sex, and village/urban-ward distribution.
Methods. An analytical observational study with a population-based cross-sectional design was conducted among 181 adult participants from 12 villages and 1 urban ward, mobilized through the empowerment of Posbindu PTM and Posyandu Lansia. The prevalence of positive results was expressed as a proportion with 95% confidence intervals (CI) calculated using the Wilson, Wald, and Clopper–Pearson methods, together with cluster design effect correction. Bivariate analysis employed Pearson's chi-square test, Fisher's exact test, the Cochran–Armitage test for trend, and the Mann–Whitney test. Multivariable analysis employed binary logistic regression, supplemented by age-stratified Mantel–Haenszel odds ratios, tests of inter-village heterogeneity (Cochran's Q and I²), receiver operating characteristic curve analysis, and sensitivity and statistical power analyzes.
Results. Of 181 participants (mean age 63.7 ± 7.0 years; 50.6% male), 30 tested positive, yielding a prevalence of 16.6% (95% Wilson CI 11.9–22.7). Prevalence was higher in men than in women (22.0% vs 11.2%; crude odds ratio 2.23; 95% CI 0.98–5.07; p = 0.071) and reached statistical significance after adjustment for age (adjusted odds ratio 2.51; 95% CI 1.03–6.08; p = 0.042) and in the Mantel–Haenszel stratified analysis (odds ratio 2.51; 95% CI 1.03–6.14). Age was not associated with a positive result, whether analyzed as a continuous variable (odds ratio 1.00 per year; 95% CI 0.94–1.06; p = 0.947), across age groups (p = 0.375), or by trend testing (Z = 0.279; p = 0.780), with an area under the curve of 0.494 (95% CI 0.377–0.612). No inter-village heterogeneity in prevalence was observed (Q = 2.77; p = 0.993; I² = 0.0%; permutation p = 0.993).
Conclusion. The 16.6% prevalence of positive fecal occult blood test results substantially exceeds the positivity rates of organized screening programs in high-income countries, with male sex emerging as the sole independent determinant. These findings support the feasibility of empowering Posbindu PTM and Posyandu Lansia as channels for screening mobilization, while underscoring the urgent need to strengthen the colonoscopy referral pathway so that the benefits of screening do not end at the detection stage.