因子分析方法在精液质量综合评价中的应用

目的:探讨因子分析方法在精液质量综合评价中的应用。方法:运用因子分析方法对正常生育力男性精液检测指标(精液量、精子浓度、精子总数、活动率、前向运动精子百分率、存活率和正常形态精子百分率、前向运动精子总数、有效前向运动精子总数、畸形精子指数(TZI)、精子畸形指数(SDI)、曲线速率(VCL)、直线速率(VSL)、平均路径速率(VAP)、精子头侧摆幅度(ALH)、直线性(LIN)、摆动性(WOB)、前向性(STR)、鞭打频率(BCF)和平均角位移(MAD)进行了分析,提取反映精液质量特征的公因子,综合评价精液质量。结果:依据累积方差贡献率达到85%的原则,共萃取6个特征值>0.8的公因子,累积方差贡献率为86.647%。6个公因子依次分别代表精子数量、运动速度、运动方向、畸形指数、精液量以及正常形态。因子综合得分的计算公式为:(36.243*F1+23.342*F2+8.910*F3+8.500*F4+5.538*F5+4.115*F6)/86.647,其中位数为-0.0180。以P5为界值,正常生育力男性各精液检测指标均达到WHO参考值范围的比例仅为79.2%;而因子综合得分达到界值的对象比例为95.1%,两者差异有统计学意义(P=0.000)。结论:在综合评价精液质量时,因子分析结果即因子综合得分指标对精液质量的判定更精确。

Application of factor analysis in comprehensive evaluation of semen quality

Objective: To explore the application of factor analysis in comprehensive evaluation of semen quality.Methods: Using factor analysis,we examined the semen samples from normal fertile men and comprehensively evaluated their quality by extracting typical common factors from the sperm parameters,such as semen volume,sperm concentration,total number of sperm,total motility,progressive motility,vitality,sperm morphology,total number of progressive motile sperm,total number of valid progressive motile sperm,teratozoospermia index(TZI),sperm deformity index(SDI),curvilinear velocity(VCL),straight-line velocity(VSL),average path velocity(VAP),amplitude of lateral head displacement(ALH),linearity(LIN),wobble(WOB),straightness(STR),beat-cross frequency(BCF) and mean angular displacement(MAD).Results: Based on the principle of the cumulative variance contribution rate of 85% or more,we extracted 6 common factors with the cumulative variance contribution rate of 86.647%,which in sequence represented sperm count,velocity,direction of movement,deformity index,semen volume and normal sperm morphology.The composite factor scores were calculated by the formula of(36.243*F1+23.342*F2+8.910*F3+8.500*F4+5.538*F5+4.115*F6)/86.647,with a median of-0.0180.With the 5th percentile as the lower reference limit,95.1% of the fertile males met the WHO limit for composite factor scores,while only 79.2% of them met the limit for semen parameters(P=0.000).Conclusion: Compared with the routine detection of sperm parameters,factor analysis or composite factor scores could give a more accurate comprehensive evaluation of semen quality.