The FDA requires that the sponsor should assess the stability of the sample after a minimum of three freeze-thaw cycles. QC samples should be thawed and analyzed according to the same procedures as the study samples. QC samples should be frozen for at least 12 hours between cycles. Freeze-thaw stability QCs should be compared to freshly prepared calibration curves and QCs.
| True Concentration | Measured Concentration 1 | Measured Concentration 2 | Measured Concentration 3 |
|---|---|---|---|
| True Concentration | Measured Concentration 1 | Measured Concentration 2 | Measured Concentration 3 |
|---|---|---|---|
| True Concentration | Measured Concentration 1 | Measured Concentration 2 | Measured Concentration 3 |
|---|---|---|---|
| QC Level | Mean Accuracy | Standard Deviation | CV (%) |
|---|---|---|---|
| High QC | |||
| Medium QC | |||
| Low QC |