Journal: Nature medicine
This was a prospective, paired, noninferiority clinical trial assessing whether an AI system could safely reduce radiologist workload in breast cancer screening by autonomously excluding low-risk mammograms from human review.
Design and population
- Timeframe: March 2022 – January 2024
- Setting: Routine screening program
- Participants: 31,301 women undergoing screening mammography
- Parallel strategies applied to all exams:
- Standard of care: double-blind human reading
- AI-supported strategy:
- AI classification: exams classified as low or non–low risk
- Low-risk exams: automatically assessed as normal (no radiologist review)
- Non–low-risk exams: double reading with AI support
Primary outcomes
- Radiologist workload
- Cancer detection rate (CDR)
- Recall rate
Key results
- Workload:
- AI strategy: reduced radiologist workload by 63.6% (nearly two-thirds fewer human reads)
- Cancer detection:
- CDR increase: 15.2% (95% CI 6.6%–24.4%)
- Absolute increase: from 6.3/1,000 to 7.3/1,000 screens (P < 0.001)
- Recall rate:
- Noninferiority: not met
- Change with AI: recall rate 14.8% higher (95% CI 9.0%–20.6%)
Modality subanalyses
- Digital mammography (DM):
- Workload reduction: −62.1%
- CDR change: increased by 1.6/1,000
- Recall rate change: increased by 1.3 percentage points
- Digital breast tomosynthesis (DBT):
- Workload reduction: −65.5%
- CDR: remained stable versus standard reading
- Recall rate: remained stable versus standard reading
Interpretation for practice
- Feasibility and impact: A partially automated AI workflow, in which low-risk exams bypass human reading, is feasible and substantially decreases radiologist workload while modestly improving cancer detection overall.
- Trade-offs: The trade-off is an increased recall rate, particularly for DM, whereas DBT maintained recall and detection performance with similar workload savings.
- Implications: These data support integration of AI triage into screening programs, especially where workforce constraints are significant, but highlight the need to monitor and manage recall rates.