Steering Committee Meeting Quality Control Committee Report February
Steering Committee Meeting Quality Control Committee Report February 8 th, 2007
Overview • Exam 4 Quality Control Surveillance • Additional Investigations
Exam 4 QC Committee Surveillance • Clinic – Anthropometry measures (intra- and inter-technician) – Form data mean, variance, outliers (BP and anthro) – Interviewer protocol adherence • CT – Blind rereads (intra- and inter-reader) – Torso phantom monitoring – Protocol Violations • Laboratory – Blind duplicate assays (group 1) • Ancillary Studies (Family, Lung, MRI, …)
Additional Investigations • • • Drift in Fasting Glucose Drift in Urinary Creatinine and Albumin MESA Family Ultrasound comparability EBCT and 64 Slice MDCT comparability Cardiac MRI Field Center differences
Fasting Glucose Drift • Tracy Investigative Subcommittee formed 9/07 • Recommendation to sample 800 specimens § 200 from each of the 4 exams § stratified by Exam quarter (50 each) § and stratified by glucose quintile (10 each). • Assay results transmitted to CC last week. • Report initiated and scheduled for release to Tracy Investigative Committee on 2/13/07.
MRI Center Differences Linear regression Number of obs = 5000 F( 15, 4984) = 446. 81 Prob > F = 0. 0000 R squared = 0. 5964 Root MSE = 25. 141 | Robust olvedm 1 | Coef. Std. Err. t P>|t| [95% Conf. Interval] + 4: COL | 12. 72629 1. 423397 8. 94 0. 000 9. 935803 15. 51677 5: JHU | 2. 613263 1. 378837 1. 90 0. 058 -. 0898654 5. 316391 6: UMN | 18. 06299 1. 380556 13. 08 0. 000 15. 35649 20. 76949 7: NWU | 9. 425192 1. 291795 7. 30 0. 000 6. 892705 11. 95768 8: UCLA | 5. 455308 1. 496009 3. 65 0. 000 2. 522471 8. 388145 age 1 c | . 3233225. 0470374 6. 87 0. 000 . 4155365 . 2311085 wtlb 1 |. 3754949. 0142763 26. 30 0. 000. 3475071. 4034827 htcm 1 |. 6318455. 0641437 9. 85 0. 000. 5060957. 7575953 gender 1 | 29. 12208 1. 170361 24. 88 0. 000 26. 82766 31. 41651 race 1 c_2 | 1. 979374 1. 342958 1. 47 0. 141 4. 612163. 653415 race 1 c_3 | 8. 72663 1. 040092 8. 39 0. 000 6. 687593 10. 76567 race 1 c_4 | 2. 444399 1. 221481 2. 00 0. 045. 049759 4. 83904 sbp 1 c |. 4466735. 0299493 14. 91 0. 000. 3879597. 5053874 dbp 1 c | . 1421031. 0598686 2. 37 0. 018 . 259472 . 0247343 htnmed 1 c | 5. 490219. 8400984 6. 54 0. 000 3. 843256 7. 137181 _cons | 75. 88663 11. 03512 6. 88 0. 000 97. 52033 54. 25293
MRI Center Differences • After adjustment for common risk factors, there appears to be a significant Field Center effect on End Diastolic Mass (on average UMN LV Mass measures are 18 grams more than WFU, JHU LVMass is 2. 6 grams more than WFU …). • Pairwise differences between all Field Centers are believed to be statistically significant. • Regressions of LV Mass Index (weight and height adjusted variant) produce similar results. • Effects also apparent for: – End Diastolic Volume – End Systolic Volume – Stroke Volume – Ejection Fraction – Cardiac Output
Routine Investigation • No evidence for – Time trends – Image quality effect – Protocol adherence effect – Technician effect – Manufacturer effect (GE vs Siemens)
CT LV Size Adjustment Linear regression Number of obs = 5000 F( 16, 4983) = 657. 68 Prob > F = 0. 0000 R squared = 0. 7310 Root MSE = 20. 525 | Robust olvedm 1 | Coef. Std. Err. t P>|t| [95% Conf. Interval] + 4: COL | -1. 062079 1. 160226 -0. 92 0. 360 -3. 336633 1. 212476 5: JHU | -1. 25548 1. 096965 -1. 14 0. 252 -3. 406015. 8950548 6: UMN | 16. 16367 1. 127796 14. 33 0. 000 13. 95269 18. 37464 7: NWU | -. 8253703 1. 068237 -0. 77 0. 440 -2. 919586 1. 268845 8: UCLA | -4. 030186 1. 154943 -3. 49 0. 000 -6. 294381 -1. 76599 age 1 c |. 1871892. 0397874 4. 70 0. 000. 1091883. 2651901 wtlb 1 |. 2996125. 0120323 24. 90 0. 000. 2760238. 3232011 htcm 1 | . 1952002. 058762 3. 32 0. 001 . 3103996 . 0800009 gender 1 | 19. 25727. 8976507 21. 45 0. 000 17. 49748 21. 01706 _Irace 1 c_2 | 1. 119526 1. 093914 1. 02 0. 306 3. 264079 1. 025027 _Irace 1 c_3 | 4. 665182. 831245 5. 61 0. 000 3. 035576 6. 294788 _Irace 1 c_4 | 1. 596157. 9849146 1. 62 0. 105 . 3347087 3. 527024 sbp 1 c |. 1749503. 0240008 7. 29 0. 000. 1278981. 2220025 dbp 1 c |. 1621186. 047622 3. 40 0. 001. 0687586. 2554786 htnmed 1 c | 3. 787789. 6741172 5. 62 0. 000 2. 466222 5. 109355 lvs |. 3632597. 0105439 34. 45 0. 000. 342589. 3839304 _cons |. 4006381 9. 054353 0. 04 0. 965 17. 34988 18. 15116
- Slides: 9