Table 1.
High- and low-risk clusters for female BC incidence using spatial scan statistics in Tehran (2008-2011)
| Optimal Gini coefficient | MSC | Clusters detected | Involved districts | At-risk population | Observed cases (O) | Expected cases (E) | Annual cases per 100,000 | O/E | RR1 | p-value | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Total BC incidence | (n=3,080) | ||||||||||
| Areas with high rates | 0.47 | 0.04 | Primary | 3, 6 | 58,039 | 217 | 55.37 | 126.4 | 3.92 | 4.14 | <0.001 |
| Secondary | 3, 4 | 29,134 | 145 | 27.79 | 165.9 | 5.22 | 5.43 | <0.001 | |||
| Tertiary | 4, 8 | 45,449 | 161 | 43.36 | 118.1 | 3.71 | 3.86 | <0.001 | |||
| Areas with low | Primary | 17, 18, 19 | 111,902 | 6 | 106.75 | 1.8 | 0.05 | 0.05 | <0.001 | ||
| rates | Secondary | 16, 20 | 124,216 | 27 | 118.50 | 7.2 | 0.23 | 0.22 | <0.001 | ||
| Tertiary | 14 | 113,341 | 23 | 108.12 | 6.8 | 0.21 | 0.21 | <0.001 |
BC, breast cancer; MSC, maximum size cluster; RR, relative risk.
1
Calculated as the observed cases divided by the expected cases within the cluster divided by the observed cases divided by the expected cases outside the cluster.