Screening guideline calibration is subject to systematic underrepresentation when eligibility thresholds are derived from trial populations that do not reflect the demographic distribution of disease risk, producing a health equity gap in which subgroups with earlier disease onset or elevated risk at younger ages fall outside age-based eligibility cutoffs. Risk-based stratification models (incorporating individualized risk score thresholds rather than fixed age/exposure cutoffs alone) can reclassify a portion of an excluded population as eligible, revealing that guideline generalizability is bounded by the demographic composition of the founding trial. This belongs to clinical epidemiology and health equity research within preventive medicine, relating to the broader methodological principle that trial-derived clinical guidelines require external validation across subpopulations before being treated as universally applicable.
Screening guideline calibration is subject to systematic underrepresentation when eligibility thresholds are derived from trial populations that do not reflect the demographic distribution of disease…