Different approaches for presymptomatic testing used in Wales
| Approach | Total | Normal/abnormal molecular result |
| (1) Two stage approach | ||
| A Blood taken at second genetic counselling session | 7 | 7/– |
| B Offer of a two step approach, rejected by the person at risk | 2 | 1/1 |
| (2) Intermediate approach | ||
| A Blood taken by family doctor or genetic nurse specialist at interval after first genetic counselling session | 3 | 3/– |
| B Blood taken at first genetic counselling session, stored until confirmation to proceed from patient. | 5 | 5/– |
| (3) One stage approach | ||
| A Blood taken at first genetic counselling session | 46 | 35/11 |
| B Blood taken by the genetic nurse specialist at home, genetic counselling clinic session only in case of an abnormal result | 9 | 5/4 |
| Total | 72 | 56/16 |