Consultation Patterns among Japanese Cedar Pollinosis Subjects at an Urban Clinic Report 2: a 20-Year Experience (1990-2009) in Chiyoda Ward, Tokyo

To determine the consultation patterns of Japanese cedar pollinosis subjects during the pollen dispersal season, we surveyed those treated at a private clinic in Chiyoda Ward, Tokyo, from 1990 to 2009. We also studied the relationship between subject numbers and pollen count. The above relationship correlated highly with linear regression equation y=0.0897x+627.47 with R2=0.7851 (p< 0.001). The relationship from 1994 to 2009, when the study began in early January, correlated highly with logarithmic regression equation y=257.43Ln(x)-1014.8 with R2=0.9542 (p