Table 9
Differences in the distribution of progesterone receptor (PR) positivity between laboratories with high assay sensitivity and those with low assay sensitivity
| Mean receptor frequency (%) | ||||
|---|---|---|---|---|
| Age of patient | High assay sensitivity | Low assay sensitivity | Mann-Whitney U | p Value |
| High assay sensitivity defined as a median score ≥13/20 in UK NEQAS assessment runs 36, 39, and 41; low assay sensitivity defined as a median score ≤12/20 in UK NEQAS assessment runs 36, 39, and 41. | ||||
| 31–45 | 63.9 | 50.7 | 33.00 | 0.035 |
| 46–50 | 69.0 | 56.9 | 40.00 | 0.082 |
| 51–55 | 61.7 | 48.0 | 35.00 | 0.045 |
| 56–65 | 60.9 | 50.2 | 44.50 | 0.132 |
| 66–75 | 63.2 | 54.7 | 47.50 | 0.174 |
| >75 | 57.7 | 44.0 | 37.50 | 0.062 |
| All ages | 62.8 | 51.4 | 35.50 | 0.048 |
