Lady K - I've had the test for both, the bloods tests the hcg and pappardelle levels and add to the accuracy of the screen test. However the screen test still holds most gravitas to your score. I was worried as being older this time your rate automatically gets higher risk but based on bloods and screen our results came out twice as low as JJ . Mw said don't have it done unless you are willing to have further tests but I think that's rubbish, I wanted test for peace of mind all was ok. As its invasive hadn't occurred to me not to have it.