Ethnic minority sample sizes in Wales, which are often insufficient to allow meaningful analysis at a level detailed enough to observe differences across specific ethnic minority groups.
Maint samplau ethnig lleiafrifol yng Nghymru, sy’n aml yn annigonol i wneud gwaith dadansoddi ystyrlon ar lefel sy’n ddigon manwl i nodi gwahaniaethau rhwng grwpiau ethnig lleiafrifol penodol.