Table 3.
Variation in RR of Meningioma Across Different Levels of Radiation Exposure Resulting From Radiotherapy
| Level of Exposure, Gy | Cases |
Controls |
RRs |
|||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Unadjusted* |
Adjusted for Intrathecal Methotrexate Exposure*† |
|||||||||
| No. | Mean Dose (Gy) | No. | Mean Dose (Gy) | RR | 95% CI | P | RR | 95% CI | P | |
| Incomplete information | 25 | 25 | ||||||||
| 0 | 3 | 39 | 1 | 1 | ||||||
| 0.01-9.99 | 6 | 2.66 | 33 | 0.88 | 1.1 | 0.1 to 7.5 | .962 | 1.8 | < 0.8 to 39.3 | .632 |
| 10.00-19.99 | 12 | 16.58 | 10 | 15.17 | 35.1 | 2.9 to 419.1 | .005 | 8.4 | 6.4 to < 10.7 | .078 |
| 20.00-29.99 | 39 | 24.76 | 15 | 23.29 | 57.8 | 6.1 to 544.5 | < .001 | 51.6 | 5.5 to < 69.5 | < .001 |
| 30.00-39.99 | 21 | 34.73 | 8 | 34.66 | 69.6 | 6.6 to 736.4 | < .001 | 567.9 | 29.3 to < 773.6 | < .001 |
| ≥ 40.00 | 28 | 46.97 | 4 | 43.38 | 94.2 | 8.7 to 1,014.0 | < .001 | 479.1 | 25.0 to < 657.2 | < .001 |
| Total | 134 | 134 | ||||||||
Abbreviation: RR, relative risk.
*
Likelihood ratio test for evidence of heterogeneity in RR across different levels of exposure to radiation: P < .001 for unadjusted analysis and for adjusted analysis.
†
Adjusted for intrathecal methotrexate exposure fitted as a categoric exposure variable.