Example of a Choropleth Map

An example of a Choropleth Map:

HIV Epidemic among Young Thai Men, 1991–2000

Figure 2. Choropleth maps of HIV prevalence in four classes of young men at time of entry into the Royal Thai Army, Thailan, 1991-2000. Location determined by residence during the previous 2 years. Prevalence is stratified by color and localized to district or group of districts so that calculations are based on > 20 men

Kalyanee Torugsa*, Scott Anderson†, Nucharee Thongsen*, Narongrid Sirisopana*, Achara Jugsudee‡, Pitak Junlananto‡, Sorachai Nitayaphan*, Suebpong Sangkharomya*, and Arthur E. Brown* 

Author affiliations: *Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; †State University of New York at Cortland, Cortland, New York, USA; ‡Army Institute of Pathology, Bangkok, Thailand

Source: http://wwwnc.cdc.gov/eid/article/9/7/02-0653-f2.htm