Table 3.
Mean total PSA detected from Puritan swabs after repeated freezing and thawing cycles
| Storage | Time of testing
|
|||
|---|---|---|---|---|
| First test | At first freeze/thaw at 3 months | At second freeze/thaw at 6 months | At fourth a freeze/thaw at 12 months | |
| First tested on Day 0 | 91.4 | 75.8 | 86.6 | 81.4 |
| Stored at room temperature without desiccant before first testing on Day 1 | 50.3 | 46.8 | 50.9 | 49.0 |
| Stored at room temperature with desiccant before first testing on Day 1 | 49.0 | 46.4 | 53.1 | 49.5 |
| Stored at −80°C before first testing on Day 1 | 86.6 | 77.1 | 84.0 | 77.3 |
| Storage | Time of testing
|
|
|---|---|---|
| First test | At first freeze/thaw after 12 months | |
| Stored at room temperature without desiccant before first testing on Month 6 | 22.0 | 11.1 |
| Stored at room temperature with desiccant before first testing on Month 6 | 28.7 | 16.6 |
| Stored at −80°C before first testing on Month 6 | 55.4 | 46.2 |
a
Data from third freeze/thaw cycle not available.