Table 27 Independent dataset characteristics and natural variability assessment.
Dataset | Source type | Collection period | Natural degradation factors | Equipment age range (mean ± SD) | Operator variability (n) | Patient demographics | Original purpose | Sample quality score (mean ± SD) | Institutional review board status |
|---|---|---|---|---|---|---|---|---|---|
ExtVal-1 (rural) | Ongoing screening program | 2019–2023 | Equipment aging, positioning errors | 8.7 ± 3.2 years (3–15 years) | 12 different operators | Rural farming communities (n = 8340) | Community health screening | 3.2 ± 0.8/5.0 | Approved (IRB-2019-045) |
ExtVal-2 (urban) | Clinical practice archive | 2020–2024 | High throughput, variable protocols | 6.3 ± 2.9 years (2–12 years) | 18 different operators | Low-income urban population (n = 12,480) | Routine clinical diagnosis | 3.6 ± 0.7/5.0 | Approved (IRB-2020-128) |
ExtVal-3 (mobile) | Mobile screening consortium | 2021–2024 | Portable equipment limitations | 4.1 ± 2.3 years (1–8 years) | 25 different operators | Underserved communities (n = 6580) | Public health outreach | 2.7 ± 0.9/5.0 | Approved (IRB-2021-074) |
ExtVal-4 (international) | Multi-site research network | 2018–2023 | Cross-population variations | 9.2 ± 3.8 years (4–16 years) | 34 different operators | Six countries, diverse ethnicities (n = 9520) | Epidemiological research | 3.4 ± 0.6/5.0 | Multi-site approval |
ExtVal-5 (pathology) | Specialized clinical centers | 2017–2024 | Early-stage detection challenges | 8.1 ± 2.7 years (5–14 years) | Expert radiologists (8) | High-risk patients (n = 4890) | Specialized diagnosis | 4.1 ± 0.4/5.0 | Approved (IRB-2017-156) |
ExtVal-6 (emergency) | Emergency department archive | 2020–2024 | Suboptimal acquisition conditions | 7.4 ± 4.2 years (2–18 years) | Non-dental personnel (22) | Emergency presentations (n = 7440) | Urgent care diagnosis | 2.9 ± 1.0/5.0 | Approved (IRB-2020-203) |
ExtVal-7 (longitudinal) | Long-term follow-up study | 2018–2024 | Temporal equipment changes | 8.8 ± 2.1 years (6–12 years) | 15 different operators | Tracked patient cohort (n = 5970) | Disease progression monitoring | 3.7 ± 0.5/5.0 | Approved (IRB-2018-089) |
