Some of these children may also have PLASC or EOTAS records but could not be linked to the WDSD due to discrepancies in recording of name, address or date of birth.
Fodd bynnag, gall rhai disgyblion gael eu cynnwys yn y cyfrifiad EOTAS ac ar CYBLD ysgol (ar gyfer ysgolion cynradd, uwchradd ac arbennig a gynhelir).