Guidance relating to sex and gender survey questions has been developed and refined further in recent years, including updates to the harmonised standard.
Mae canllawiau sy’n ymwneud â chwestiynau mewn arolygon am ryw a rhywedd wedi cael eu datblygu a’u mireinio ymhellach dros y blynyddoedd diwethaf, gan gynnwys diweddariadau i’r safon wedi’i chysoni.