These are both a potential source of information as well as potential candidates for a boosted sample if that is an effective way to meet Welsh Government needs.
Mae’r rhain yn ffynhonnell bosibl o wybodaeth, ynghyd â bod yn bosibiliadau o ran cynyddu maint y sampl, os yw hynny’n fodd effeithiol o ddiwallu anghenion Llywodraeth Cymru.