Table 2. Differences in parameter alterations based on the 1999 and 2010 WHO classifications.
Alterations WHO Absolute Difference (%) Relative Difference (%) p
1999
n=477
(%)
2010
n=477
(%)
Total concentration 163 (34.2) 162 (34.0) 0.2 0.6 1.000
Concentration/ml 170 (35.6) 146 (30.6) 5.0 14.0 <0.001
Motility a + b 310 (65.0) 151 (31.7) 33.3 51.2 <0.001
Morphology 335 (70.2) 50 (10.5) 59.7 85.0 <0.001
Vitality 400 (87.9) 175 (38.5) 49.4 56.2 <0.001
With at least 1 abnormal parameter* 401 (84.1) 223 (46.8) 37.3 44.4 <0.001
With at least 2 abnormal parameters* 293 (61.4) 112 (23.5) 37.9 61.7 <0.001

*The patient had alterations in any of the four parameters: total concentration, concentration/ml, motility and morphology. WHO: World Health Organization.