BACKGROUND: We sought to measure time and identify predictors of timely follow-up among a cohort of racially/ethnically diverse inner city women with breast and cervical cancer screening abnormalities. METHODS: Eligible women had an abnormality detected on a mammogram or Papanicolaou (Pap) test between January 2004 and December 2005 in 1 of 6 community health centers in Boston, Massachusetts. Retrospective chart review allowed us to measure time to diagnostic resolution. We used Cox proportional hazards models to develop predictive models for timely resolution (defined as definitive diagnostic services completed within 180 days from index abnormality). RESULTS: Among 523 women with mammography abnormalities and 474 women with Pap test abnormalities, >90% achieved diagnostic resolution within 12 months. Median time to resolution was longer for Pap test than for mammography abnormalities (85 vs 27 days). Site of care, rather than any sociodemographic characteristic of individuals, including race/ethnicity, was the only significant predictor of timely follow-up for both mammogram and Pap test abnormalities. CONCLUSIONS: Site-specific community-based interventions may be the most effective interventions to reduce cancer health disparities when addressing the needs of underserved populations.