The relationship between the reference value of erythrocyte sedimentation rate and geographical factors.

In order to provide a scientific basis for a unified standard of the reference value of erythrocyte sedimentation rate (ESR) in China, the reference value of healthy people's ESR has been collected. The relationship between the reference value of ESR and geographical factors is examined in this paper. Altitude is the most important factor affecting the reference value of ESR, which decreases with increasing altitude; the relationship is quite significant. The method of stepwise regression analysis was used to deduce two regression equations: Y1 = 12.08 - 0.00222X1 + 0.00114X5 +/- 2.95, Y2 = 18.81 - 0.00323X1 + 0.239X4 +/- 4.70. If the geographical factor value of a particular area in China is known, the reference value of ESR of Chinese people can be calculated by means of the regression equations. Furthermore, the dependence on geographical factors in China can be classified as six districts: Qingzang, Southwest, Northwest, Southeast, North and Northeast.