Objective To determine whether there is an association between dermatologist density and melanoma mortality.
Design A regression model was developed to test the association between melanoma mortality and dermatologist density, controlling for county demographics, health care infrastructure, and socioeconomic factors. Data were collected from the Area Resource File, US Centers for Disease Control and Prevention, and National Cancer Institute's Surveillance, Epidemiology, and End Results program and National Program for Cancer Registries.
Setting US counties.
Patients Melanoma mortality and incidence data were reported as age-adjusted mean rates per 100 000 people from January 2002, through December 2006.
Main Outcome Measure The primary outcome measure was melanoma mortality rate per 100 000 people at the county level.
Results Geographic variation exists in the distribution of dermatologists across the United States. Multivariate analysis demonstrated that the presence of 0.001 to 1 dermatologist per 100 000 people was associated with a 35.0% reduction in the melanoma mortality rate (95% CI, 13.4%-56.6%) when compared with counties with no dermatologist. The presence of 1.001 to 2 dermatologists per 100 000 people was associated with a 53.0% reduction in the melanoma mortality rate (95% CI, 30.6%-75.4%). Having more than 2 dermatologists per 100 000 people did not further lower melanoma mortality rates.
Conclusion Within a given county, a greater dermatologist density is associated with lower melanoma mortality rates compared with counties that lacked a dermatologist.