I. We made a factoranalytical research of these indicators by Thurstone's centroid method and extracted four common factors.
II. We calculated the Z-scores (I) of the above 19 variables which were closely related with four common factors and the Z-scores (II) of the another 5 variables by urban and rural which were live birth rate, premature infant birth rate, infant mortality rate, α-index and maternal death rate, and computed the cofficient of correlation between the Z-scores (I) and the Z-scores (II), and investigated the influence of environmental factors on maternal and child health.

I. We made a factoranalytical research of these indicators by Thurstone's centroid method and extracted five common factors.
II. We calculated the Z-scores (I) of the above 12 variables which were closely related with five common factors and the Z-scores (II) of the another 10 variables by prefectures which were live birth rate, premature infant birth rate, live birth rate by hospitalization, infant mortality rate, neo-natal mortality rate, α-index, artifical foetal death rate, etc., and computed the cofficient of correlation between the Z-scores (I) and the Z-scores (II), and investigated the influence of environmental factors on mate rnaland child health.