The persistent uncertainty around ductal carcinoma in situ screening creates a challenging paradox for millions of women: aggressive detection programs may identify lesions that would never cause harm, yet delayed diagnosis could miss genuinely threatening cancers. This computational modeling analysis reveals how dramatically overdiagnosis rates fluctuate based on screening design choices. Using the validated SimDCIS microsimulation model, researchers quantified overdiagnosis across diverse screening scenarios, finding rates spanning from a minimal 1% to a substantial 27% depending on program parameters. The baseline scenario—biennial screening from ages 50-74 with 76% compliance—yielded a 20% overdiagnosis rate, meaning one in five DCIS cases detected would never have become clinically relevant without screening intervention. Critical variables emerged from the analysis: shorter follow-up periods artificially inflated overdiagnosis estimates, rising from 20% at 25-year follow-up to 27% at just two years. Starting screening at older ages paradoxically reduced overdiagnosis rates, dropping from 15% when beginning at age 74 to merely 1% at age 40. More frequent screening increased overdiagnosis, while higher participation rates showed modest increases. These findings illuminate a fundamental methodological issue plaguing DCIS research—the wide range of reported overdiagnosis estimates (20-91% across studies) likely reflects inconsistent analytical approaches rather than genuine biological variation. The research suggests that meaningful DCIS policy discussions require standardized methodology with minimum 20-year follow-up periods. For health-conscious adults, this underscores the complexity of screening decisions and the importance of individualized risk-benefit discussions with healthcare providers.