ISPD: not that serious of a concern after all

ISPD logoOver at the Prenatal Information Research Consortium (PIRC) blog I have a post noting the “sea-change” in the International Society for Prenatal Diagnosis’ position on noninvasive prenatal screening. Here are a few other notes from the ISPD’s updated statement on NIPS.

Readers who have been with this blog from the beginning may recall that in 2013, the ISPD issued a rapid response statement to NIPS entering the commercial market. While I questioned whether the statement lacked justification, I did appreciate ISPD expressing a “serious concern” about NIPS:

The current absence of specific guidelines for quality control and quality assurance for cfDNA screening is a serious concern.

That was from the ISPD’s 2013 statement when ISPD limited the offering of NIPS to women with an increased chance for having a child with Down syndrome.

In the updated 2015 statement, though acknowledging none of these specific guidelines for quality control have either been established nor proposed by the NIPS labs, the ISPD has instead gone ahead and recommended that all pregnant women be offered NIPS, AKA the “sea-change.”

So, not that serious of a concern after all.

Like the NSGC, the ISPD recognizes that the important figure in screening technology is not just a tests sensitivity/specificity, but what its positive predictive value (PPV) is:

The efficacies of screening protocols are assessed by consideration of the detection rate (DR, or sensitivity), false-positive rate (FPR), and positive predictive value (PPV), or odds of being affected given a positive result (OAPR). These population-based screening performance indices are of considerable value in comparing different protocols. PPV and OAPR are strongly dependent on the prevalence of the disorder.

But in the table at the end of the statement, the ISPD lists the the PPV/OAPR for traditional screening tests and for NIPS …? Nothing. NIPS laboratories like Sequenom, Natera, Ariosa, and Illumina do not report out their tests’ PPV/OAPR. So, the ISPD says that PPV/OAPR are “of considerable value,” but the NIPS labs don’t provide them, … and ISPD still recommends offering NIPS to every woman without these indices of considerable value.

Similarly, the ISPD says a lot of good things that are needed for ethical patient care, but acknowledges that none of them exist at the time:

  • “ISPD recognizes the challenge associated with explaining the expanding range of disorders that can be included in screening panels as well as the complexity of the various testing alternatives. To help meet this growing need, we support additional professional education for obstetricians and other healthcare personnel involved in screening, development of patient educational materials, and increased availability of genetic counseling.”
  • “ISPD supports the wide availability of affordable, high quality prenatal screening for clinically significant chromosome abnormalities together with appropriate patient counseling and followup diagnostic testing.”

(emphasis in original). So, here is what will happen and what will not based on the ISPD’s statement:

  • More women will be offered NIPS.
  • More 3d party payors, public and private, will decide to cover just the cost of the testing.


  • More women will not receive the counseling they should.
  • More doctors and their staff will incorrectly report the test results to these women as “99% accurate.” And
  • More women will be given nothing else to help them understand the tested-for condition and available support services.

The ISPD’s “serious concern” from 2013 seems to not be that serious after all. But its 2015 statement will have a serious impact on the mothers who are offered the testing by health care providers who lack understanding about NIPS and who will not get the counseling they should for making informed decisions.


  1. When I read the headline I thought ISPD was the International Society for Preventing Disability, then I realised you were talking about prenatal diagnosis. Sheep and wolves.

    There is a certain inevitability in this and the writing has been on the wall for some time now, underpinned by a culture of testing and choice. As we enter the end game our community has now been reduced to cute pictures, stories of ability and success and advocating informed choice.

    Society has removed dignity from our unborn brothers and sisters. Society has said our children’s value comes through achievement. Down syndrome advocates have largely fallen into that position. Add NIPS into that mix and there is an inevitable outcome.

    But we have erred in our understanding. Dignity does not come from utilitarian values of achievement, nor is it subject to another’s choice. Dignity comes from being. When we remove the dignity from others we remove it from ourselves.

    People wonder why? To me it is self evident. The pro-choice utilitarian culture offends human dignity. Do we face a grim future for Down syndrome. Yes. But now is the time to have peace with that and celebrate dignity. Leave the brokenness to the rest.


  1. […] Prenatal Diagnosis (ISPD), arrived at its statement by a committee the super-majority of which was comprised of members with declared conflicts of interest for receiving funds or being employed by the NIPS […]

Leave a Reply

%d bloggers like this: