... numbers of HPs and OPs.The number of HPs increased more than threefoldbetween 1974 and 2004, and exceeded the number of OPsduring 1974 and 1984. Even though the total numbers of HPs (N1, N2, N3 and ... work in each of the classes of 1970, 1980 and 1990. The numbers of HPsin the classes of 1970,1980 and 1990 were 2450, 5862 and 6573, respectively.Among the class of 1970, 57% of physicians ... 0.01ns: not significant; na: not availableR2 for the analyses of the classes of 1970, 1980 and 1990 were 0.24, 019 and 0.17, respectively.Human Resources for Health 2009, 7:7 3 http://www.human-resources-health.com/content/7/1/73Page...