The calculation of expected numbers of cancers in the cohort was based on cancer registry data for the same population from which the cancer patients were drawn.
Cases and population data for registries based within the same country were combined, creating a total of 62 data points (5 from Africa, 7 South and Central America, 12 North America, 16 Asia, 29 Europe 29 and 3 Oceania 3).
Group patterns 3 and 5 contain only one child pattern, so their registries are the same as registries of these child patterns.
Controls were selected from pregnancy registries in the same areas.
The reasons for these inconsistencies are unclear, but not all previous studies were supplemented by data linkage with cancer registries to the same extent of the SHCS.
In 1996 the National Intensive Care Evaluation NICEE) registry was set up in The Netherlands for the same reason.
The mean SMWD for the 215 counties in the 12 SEER registries is 0.43, the same as the average for the 3,141 counties in the US.
Third, we obtained data that had been collected and coded by eight different state and territory registries and collated by the NCSCH, and it is unclear whether each registry used the same method for handling sub-site cancers.
For example, at a single institution the Anatomic Pathology -Lab Informandon Systhe and the local tumor registry may have data available for the same CDE regarding tumor histology or staging information.
