TABLE 4—

Blinder-Oaxaca Decomposition Method: Observed Versus Unobserved Factors Accounting for STD Incidence Rate Differences: US Longitudinal Study of Local Public Health Systems, 2006

Decomposition of STD Incidence Rate Differences by Local Board of Health Role	Mean STD Incidence Rate per 100 000	Decomposition of STD Incidence Rate Differences by Local Public Health System Type	Mean STD Incidence Rate per 100 000
No board of health (Ref): predicted ln(STD)	6.29	Independent comprehensive (Ref): predicted ln(STD)	6.24
Board of health with governance role: predicted ln(STD)	5.50	Distributed limited: predicted ln(STD)	5.51
Total difference	−0.79		−0.73
Total explained	−0.49 (61.9%)		−0.47 (65.0%)
Individual significant factors of total explained differences, %
Black	54.12		72.67
Male–female ratio	11.60

Note. ln(STD) = log-transformed STD incidence rates; STD = sexually transmitted disease.