Table 1.
Principal component analyses (PCA) based on individual kinematic parameters of all sperm cells evaluated by computer-assisted sperm analysis (CASA) system. As a result, two PCA components were obtained.
| Principal Component | Variance | Parameter | aij2 |
|---|---|---|---|
| Component 1 | 58.04% | LIN | 0.94 |
| WOB | 0.81 | ||
| STR | 0.79 | ||
| VSL | 0.62 | ||
| VAP | 0.48 | ||
| BCF | 0.44 | ||
| MAD | 0.28 | ||
| Component 2 | 22.16% | ALH | 0.88 |
| VCL | 0.78 | ||
| DANCE | 0.93 | ||
| Total | 80.20% |
The loading factor (aij2) represents the highest association between a given sperm kinematic parameter and the corresponding principal component. LIN, linearity; WOB, wobble; STR, straightness; VSL, straight-line velocity; VAP, average path velocity; BCF, beat-cross frequency; MAD, mean angular displacement; ALH, amplitude of lateral head displacement; VCL, curvilinear velocity; DANCE, VCL × ALH.