Comparison of Probe Efficiencies and Their Variability for 3 Devices (and Practices)
| Device | n | Nominal efficiency (cps/MBq) | Measured CV | Comment |
|---|---|---|---|---|
| Site2Old | 29 | 881 | 4% | QC limits derived with explicit test measurements that served as QC estimates for Site2New |
| Site2New | 20 | 910* | 4% | From clinical data using QC estimate from Site2Old as guideline |
| Site1New | 22 | 1,025* | 11%* | From clinical data without using any efficiency QC |
*P < 0.05 in comparison to Site2Old.