However, individuals only need to make a formal complaint should they so wish, the investigation process places the same requirement on health bodies to respond to patients and families.
Fodd bynnag, nid oes angen i unigolion wneud cwyn ffurfiol oni bai eu bod yn dymuno gwneud hynny; mae'r broses ymchwilio yn gosod yr un gofyniad ar gyrff iechyd i ymateb i gleifion a theuluoedd.