Journal club MCQ November 2019

Objective of article

Upon completion of this educational activity, the participant will be able to:

Recall the prevalence of common chromosomal abnormalities (Q1)
Discuss the risk of miscarriage related to different screening strategies (Q2)
Compare the economic impact of different screening/diagnosis strategies when used in populations with similar risk (Q3)
Assess the potential problems with cell-free testing when used in broader populations with lower risk of chromosomal abnormalities (Q4 and 5)

Question Title

* 1. Which of the following statements is true regarding the prevalence of chromosomal abnormalities.

a. Trisomy 13 is the most common trisomy with a prevalence of 19.4 per 10.000 livebirths

b. The prevalence of Trisomy 18 and 13 are rarer compared to Trisomy 21 with prevalence of 2.3 and 1.4 per 10.000 livebirths.

c. The overall prevalence of other non-specified chromosomal abnormalities is higher than Trisomy 21

Question Title

* 2. According to the results of SAFE21 trial, in women with a first trimester screening risk between 1/5 and 1/250 the sequential use of cell-free DNA and invasive testing over direct invasive testing has the following effect on miscarriage rates

a. It reduces the miscarriage rates significantly

b. It increases the miscarriage rates significantly

c. The risk difference was in favour of sequential testing with cell-free DNA and invasive testing (risk difference= -0.03%) but the effect was insignificant

Question Title

* 3. According to the results of this study, which of the following is a potential disadvantage of cell-free DNA testing over amniocentesis when used on women with the same risk intervals.

a. Cell-free DNA testing increases the overall healthcare costs when compared to direct invasive testing

b. Cell-free DNA testing can miss other unbalanced chromosomal abnormalities

c. Cell-free DNA increases the costs related to specialist consultation

Question Title

* 4. The incorporation of cell-free DNA testing in women with lower risk cut-offs for chromosomal abnormalities has the following effect

a. It increases the number of antenatally detected Trisomy 21 cases

b. It increases the overall healthcare costs but the cost-reduction achieved by abandoning first-trimester screening counterbalances the increase

c. It boosts the antenatal detection of abnormalities which may be missed by traditional karyotyping

Question Title

* 5. What would be the detrimental effects of screening with cell-free DNA testing in the general population

a. The cost increase per additional detected anomaly would be over 9 million Euros.

b. It wouldn’t increase the overall detection of Trisomy 21 compared to historical strategies

c. It would increase the miscarriage rates