On the other hand, ONS did not have access to EOTAS data so such children in this dataset would have appeared as missing in the ONS analysis.
Ar y llaw arall, nid oedd gan y SYG fynediad at ddata EOTAS felly byddai plant o’r fath yn y set ddata hon wedi ymddangos fel pe baent ar goll yn nadansoddiad y SYG.