SG women prefer safety for Down syndrome screening
Women in Singapore who choose to undergo prenatal diagnosis of Down syndrome prefer test safety, while health professionals (HPs) prioritize accuracy of results over other attributes, a recent study has shown. Thus, awareness of differences in women’s preferences is essential in order for HPs to provide nonbiased counselling.
“In addition, HPs need to give patients adequate information on the full range of tests available, as well as spend time explaining the benefits and limitations of each option while showing sensitivity to the cultural differences among their patients,” researchers noted.
A discrete choice experiment was conducted involving 69 HPs and 301 women in Singapore, in which researchers evaluated preferences for four prenatal test attributes, namely accuracy, time of results, risk of miscarriage and amount of information provided.
The authors obtained data on demographics and ranked preferences for test attributes, and participants were presented with a direct choice question about noninvasive prenatal testing (NIPT), invasive prenatal diagnosis (IPD) or neither test. Conditional logistic regression was used to analyse the data.
Test safety was prioritized by women, whereas test accuracy was the main preference of HPs above all other attributes. Of the 237 women who ranked the attributes, 98 (41.4 percent) rated safety as the most important. Accuracy was the second highest rated aspect. [Singapore Med J 2017;58:298-310]
The least important attribute of the test was time of results, which was ranked by almost half of the women (49.4). Cost was the second least important aspect. On the other hand, 64.1 percent of HPs rated accuracy as the most important attribute, with safety as the second most important.
“Overall, we found that when making decisions regarding prenatal testing, women in Singapore, like those in other countries, place greater emphasis on test safety, while HPs place higher value on accuracy and early testing,” researchers said. [Genet Med 2012;14:905-13; Prenat Diagn 2015;35:549-57; Eur J Hum Genet 2016;968-75; Prenat Diagn 2012;32:674-9]
When presented with a direct choice of NIPT, IPD or neither test, NIPT was more likely to be selected by women aged ≥35 years, those with previous miscarriage or who knew a child with Down syndrome. Chinese women preferred NIPT, while Indian women preferred IPD.
“Given a direct choice between NIPT and IPD, previous miscarriage, age ≥35 years, knowing a child with Down syndrome, Christian faith and Chinese ethnicity were indicators for selection of NIPT,” researchers said.
“Interestingly, although women receiving both subsidized and private healthcare have demonstrated no significant difference with regard to preferences for any of the test attributes, private patients would prefer to opt for NIPT, while subsidized patients would prefer IPD when given a direct choice,” they added.
Although IPD has long been used to prenatally diagnose Down syndrome, it carries a small risk of miscarriage. On the other hand, NIPT, a highly sensitive screening test using cell-free DNA in maternal blood, is not associated with a miscarriage risk, but it confers a small risk of false-positive and false-negative results.
“The implementation of these procedures into clinical practice requires an understanding of stakeholder preferences,” researchers said.