From: Diet-related chronic disease in the northeastern United States: a model-based clustering approach
Urbanization level | Classification rule |
---|---|
Metropolitan counties | |
 Large central metro | Populations of 1 million or more that |
 | 1. Contain the entire population of the largest principal city, or |
 | 2. Have their entire population contained in the largest principal city, or |
 | 3. Contain at least 250,000 inhabitants of any principal city |
 Large fringe metro | Populations of 1 million or more that did not qualify as large central metro counties |
 Medium metro | Populations of 250,000–999, 999 |
 Small metro | Populations of 50,000–250,000 |
Non-metropolitan counties | |
 Micropolitan | Populations of 10,000–49,999 |
 Noncore | Populations less than 10,000 |