Question

Prenatal Screening test Prenatal screening is a non-invasive type of testing that is available to all pregnant individuals in Ontario. Non-invasive means that there is no risk to the pregnant person or the baby. Screening uses ultrasound, blood work or some combination of both to get information about the likelihood of a baby having a specific health condition. Screening tests do not tell you for sure if the baby has the condition, only what the chance is. A physician will review the test results and based on maternal age and genetic history may recommend additional invasive tests A negative test result means the chance that that baby has Down syndrome or trisomy 18 is LOWER than the specific cut-off set by the centre. A screen positive test means the chance that the baby has Down syndrome or trisomy 18 is HIGHER than the specific cut-off set by the centre. The chance of Chromosome condition (Down Syndrome and trisomy 18) depends on maternal age. Integrated Prenatal Screening (IPS) that includes both blood work and ultrasound is offered to pregnant women from week 11. Of every 100 pregnancies with Down Syndrome, about 90% will be detected. However, there is a 4% chance of false positive The data shows the IPS test results of 1000 pregnant woman from two hospital units of province ABC that follows the same protocol. Five rows of the data are shown below Hospital units CaselD Materna Positive test result 40 wellba Health famil e35 Wellba 40 Health family 4 <35 Wellba <35

Answer 1

1. Variables represented in data set are:

Data set	Data type
maternal age [in weeks]	integers [numerics]
genetic history	varichar [variable characteristics like alpha-numerics]
Blood tests [lab]	integers
Ultrasound [imaging]	varichar
combination [both lab and imaging]	varichar
Results	varichar

2. categories of maternal age:

<35

>40

3. Frequency distribution:

Both the hospital units show < 35 has relatively less risk as their results were negative. And >40 years have 50% relative risk for not getting and getting the possibility of chromosomal disorders and down syndrome by showing the result of one positive and one negative for the age group more than 40.