Table 1.
Variables and Definitions
| Variable | Definition and units | Min | Max | Mean | SD |
| Dependent variable | |||||
| DONORS | Donor rate in census tract | 1 | 683 | 82.96 | 60.38 |
| Socio-economic and demographic characteristics | |||||
| POP15TO24 | Proportion of population of 15-24 years of age in census tract |
0.04 | 0.66 | 0.14 | 0.03 |
| POP25TO54 | Proportion of population 25-54 years of age in census tract |
0.15 | 0.77 | 0.44 | 0.06 |
| POP55TO64 | Proportion of population 55-64 years of age in census tract |
0.02 | 0.26 | 0.11 | 0.03 |
| POP65+ | Proportion of population of 65+ years of age in census tract |
0.00 | 0.68 | 0.13 | 0.07 |
| ENGLISH | Proportion of English-speaking population in census tract |
0.03 | 1.00 | 0.69 | 0.20 |
| IMMIG | Proportion of immigrant population in census tract |
0.00 | 0.82 | 0.26 | 0.18 |
| UNEMP | Proportion of unemployed population in census tract |
0.00 | 0.12 | 0.03 | 0.01 |
| HEALTHOCC | Proportion of population in census tract in health-related occupations |
0.00 | 0.13 | 0.03 | 0.01 |
| HIGHED | Proportion of population in census tract with bachelors degree or higher |
0.00 | 0.68 | 0.21 | 0.11 |
| Ave Household Income | Average household income ($10,000) | 1.73 | 81.08 | 7.91 | 3.96 |
| Geographic variables | |||||
| CMAPOP | Total CMA population (1,000,000s) | 0.06 | 5.11 | 1.93 | 1.99 |
| City Name | City-specific dummy variable | ||||
| Service variables | |||||
| Pop Based Access | Proportion of population-based accessibility within 4 km band (beds-hour/1000 people) | 0.00 | 481.74 | 34.63 | 61.53 |