Table 1. Evaluation of seasonality of birth by histology, gender and age.
| Histology |
Walter and Elwood's test
|
||||
|---|---|---|---|---|---|
| ICCC-2 | Cases | χ 2 | P-value | Theta (θ) | Peak-month |
| Ependymoma | 162 | 8.0 | 0.02 | 13.81 | January |
| Astrocytoma | 607 | 1.45 | 0.48 | ||
| PNET | 270 | 0.61 | 0.74 | ||
| Other glioma | 76 | 3.28 | 0.19 | ||
| Other specified intracranial and intraspinal neoplasm | 199 | 1.63 | 0.44 | ||
| Unspecified intracranial and intraspinal neoplasm | 326 | 0.85 | 0.65 | ||
| All CNS tumours | 1640 | 0.37 | 0.83 | ||
| Ependymoma by age and gender | |||||
| 0–4 years | 69 | 2.2 | 0.34 | ||
| 5–19 years | 93 | 10.3 | 0.006 | −4.30 | December |
| Boys | 88 | 4.0 | 0.13 | ||
| Girls | 74 | 9.7 | 0.008 | −13.78 | December |
CNS=central nervous system; ICCC-2=International Childhood Cancer Classification second edition; PNET=primitive neuroectodermal tumour.