Improving Surveillance of Sexually Transmitted Diseases through Geocoded Morbidity Assignment

Area of Science:

• Public Health
• Epidemiology
• Geographic Information Systems (GIS)

Background:

• Sexually transmitted disease (STD) surveillance data accuracy is crucial for effective public health interventions.
• Inaccurate case assignment can lead to misallocation of resources and skewed understanding of disease burden.
• Geocoding offers a potential solution for improving the spatial accuracy of public health data.

Purpose of the Study:

• To assess the added value of geocoding for enhancing STD surveillance data quality.
• To evaluate the impact of geocoding on decision support through the redistribution of inaccurately assigned morbidity.
• To analyze the effect of geocoding on STD rates and rankings in Richmond, Virginia.

Main Methods:

• Geocoding of STD data in Virginia from 2002 to 2006.
• Assessment of geocoded output files and reassignment of discordant morbidity cases.
• Chi-square analysis and calculation of crude odds ratios to compare assignment proportions and estimate reassignment likelihood.

Main Results:

• 81% of 149,229 reported STD cases were successfully geocoded; 7% of geocoded addresses were reassigned.
• Approximately 76% of all reassigned cases occurred within Richmond, Chesterfield, and Henrico counties.
• Geocoding reduced Richmond's reported morbidity by 18% and increased Chesterfield and Henrico morbidity by 17% and 55%, respectively, impacting STD rankings.

Conclusions:

• Geocoded morbidity reassignments were statistically associated with declining STD rates.
• Implementation of geocoding as a data quality process improved epidemiologic analyses and prevention planning.
• Geocoding significantly impacts surveillance data, leading to more accurate public health assessments and resource allocation.