Why do state cancer registries require a patient’s street address, county, and zip code?

State cancer registries require a patient’s street address, county, and zip code primarily for geocoding and investigating cancer clusters.

Geocoding involves converting the patient’s address into a geographic point, allowing researchers to analyze the spatial distribution of cancer cases. By mapping this information, public health officials can identify areas with unusual patterns or higher incidences of specific cancers, which might suggest environmental or socioeconomic factors contributing to the disease.

Additionally, having detailed location information is crucial for investigating cancer clusters—groups of cancer cases that occur in close proximity over a specific time period. This detailed geographical data enables epidemiologists to look for links between cancer rates and potential environmental hazards in defined areas, leading to targeted public health responses or further research.

Thus, the requirement of a street address, county, and zip code serves both purposes, making the option that encompasses both geocoding and investigating cancer clusters the most comprehensive and correct answer.