ABGC Updates

Studying for Domain 3 of the ABGC Board Exam: Testing and Interpretation

This article is part of a series by ABGC designed to provide recommendations for additional resources and topics to prepare for the CGC exam. This article covers one exam content category and is meant to provide suggestions based on one genetic counselor’s exam preparation experience. Please note that these are suggestions only and are not meant as an exhaustive guide or exclusive study resource. 

On your journey to studying for the American Board of Genetic Counseling (ABGC) Certification Examination, you’ll at a certain point turn to Domain 3: Testing Interpretation, Testing Options, and Reproductive Risk Management.

About a year ago, I was in your shoes, finishing up the craziness of grad school, juggling thesis work, final presentations, job interviews, final exams and the looming graduation ceremony. On top of it all, the board exam seemed like an insurmountable task with so many topics. I understand it is difficult to know where to start. When I began my journey, I decided to start where my interests took me and began studying for Domain 3. 

My Study Strategies for Domain 3 of the ABGC Board Exam

To begin my studying for this section of the ABGC exam, I dove deeper into the specific topics and subtopics. Below is a rough guide for how I broke this section down and the resources I found particularly helpful. 

1. I dove deep into test methodologies.

For this section of the ABGC exam, I focused on the generalities of testing options and then dove deeper into specific methodologies and clinical utility. I felt that if I had a deep understanding of the test methodologies, limitations and result types, I would be able to apply that knowledge to all genetic conditions, rather than memorizing which test is best for each condition. 

To further develop that deep understanding of laboratory tests, I relied heavily on the book “Practical Genetic Counseling for the Laboratory” by Goodenberger, Thomas, and Kruisselbrink (Goodenberger et al., 2017). I specifically reviewed Chapters 4, 5 and 9, leaving Chapters 6 and 7 for later topics (see below). Here, I focused on a few big questions:

  • What can this test tell me?
  • What can this test NOT tell me?
    • What other test COULD tell me this missing information?
  • Who would this test benefit (eg. cancer, prenatal, pediatrics, etc.)?
  • What sample type is needed and why?

2. I focused on math: specificity, sensitivity, PPV, NPV, Bayes, etc.

I am a math person, but even so, I struggled with these calculations. Once I developed a system for understanding and solving these problems, they became much less intimidating. I started with the basics and tried more complex problems as my confidence grew. I felt that if I was able to easily solve a complex Bayes problem in practice, the exam questions would be a breeze. 

A great place to start when studying for the “math section” is the book “Introduction to Risk Calculation in Genetic Counseling” by Ian D. Young (Young, 2007). This book covers a great deal of probability and math that might be valuable for a genetic counselor. For the ABGC exam, Chapter 1.4 on Bayes Theorem as well as the case scenarios at the end of the chapters are particularly helpful and good practice.

One of the most helpful study materials for this section was the University of Minnesota’s Genetic Counseling Statistics self-paced course. Fortunately, I had access to this course as it was included in our GC program’s second year. If you do not have access to this course, you can purchase it on the University of Minnesota website. This course covers a variety of topics including Bayes, PPV, NPV, sensitivity, specificity and different inheritance patterns. The videos were excellent sources of knowledge for me, and the practice questions really helped sharpen my skills. With the purchase, you get access for an entire year, meaning you can always go back and review the videos and practice problems at your own pace and as many times as you need. 

With these resources, I tried to do at least three practice problems every week, prior to the exam, to keep up my skills. I would also re-write some of the practice problems with different or more information to have “new” problems to try out later. 

3. I reviewed testing options.

I found a fair amount of overlap between the testing options, testing methodologies and reproductive risk management. Therefore, some of the chapters listed in other sections may also be useful when studying this section, and vice versa. I generally focused on understanding the different types of testing options (diagnostic, screening, predictive, somatic, etc.) and common indications for each. 

In the book “Practical Genetic Counseling for the Laboratory” by Goodenberger, Thomas and Kruisselbrink, I used chapters 6 and 7 (Goodenberger et al., 2017). These chapters focus on biochemical testing and prenatal screening. As mentioned earlier, these chapters include material that is applicable to other sections in Domain 3. 

I found the book “Foundations of Perinatal Genetic Counseling : A Guide for Counselors” by Mathiesen and Roy helpful when studying for Domain 3, specifically testing options and reproductive risk management (Mathiesen &R Roy, 2018). For this section, I specifically focused on chapters 3, 4 and 6. These chapters relate to prenatal screening, diagnosis and carrier screening. Again, some of these chapters also have information that is useful to other sections of Domain 3. 

In addition to various textbooks, I reviewed professional guidelines surrounding testing options. When reviewing these guidelines, I focused less on memorizing the specific, detailed guidelines, but more on a general overview of the guidelines and common situations where I might need to utilize these guidelines as a GC. I reviewed various guidelines set forth by groups including the National Comprehensive Cancer Network (NCCN), American College of Medical Genetics (ACMG), American College of Obstetrics and Gynecologists (ACOG), and National Society of Genetic Counselor (NSGC) guidelines. Specifically, these recommendations may be useful for review:

I took a closer look at conditions with atypical testing options. For example, when we think of somatic testing, we commonly think about this in a cancer setting. In certain scenarios, somatic testing may be appropriate in a pediatric setting for conditions such as Mc-Cune Albright. Knowing these little exceptions was helpful during the ABGC exam. 

4. I studied reproductive risk management.

Similar to previous sections in Domain 3, there was a fair amount of overlap between the reproductive risk management section and others. This category felt a bit more unique as this is where I began to dive deeper into a specific specialty. For me, this was also one of the most difficult sections in Domain 3, as I had less exposure to prenatal clinics. 

Again, I found the book “Foundations of Perinatal Genetic Counseling : A Guide for Counselors” by Mathiesen and Roy helpful, specifically chapters 7 and 8 (Mathiesen &R Roy, 2018). I used Chapters 1 and 5 later in studying, when I specifically reviewed prenatal counseling. Chapters 7 and 8 focus on pregnancy management and assisted reproductive technologies. 

Similarly to previous sections, I also reviewed professional guidelines. For this section, I specifically took a closer look at the recommendations set forth by ACOG and ACMG. I mainly focused on generally reviewing the guidelines rather than fully memorizing them. In addition to the recommendations listed above, the following recommendation may be useful for review:

Additional Tips and Tricks for Studying for Domain 3

I tried to always take advantage of study sessions with peers or others in the genetics community in general. This was a great way for me to brush up on the skills and knowledge in Domain 3 and have a social connection while studying. I enjoyed attending review sessions with various groups including other GC students, other practicing GCs, and medical geneticists. It was helpful to discuss problems as a group and hear the different ways others approach problems.

When I found myself struggling with a specific topic, I would write my own ABGC board exam-style questions. This forced me to dive deep into the topics and develop tricky questions and answers. I shared these questions with my study groups, and it was a great resource for others as well. 

For this domain of the ABGC exam, I found myself drawing and watching videos, more than for other sections. Although I knew this would not be required on the exam, writing out the lab processes and possible results gave me a visual to think back to during the exam. 

Tackling the certified genetic counseling exam is a huge feat. Take your time planning out your own route and try to stick to it as best you can as to not get behind. Be patient with yourself and know that your hard work will pay off.


References

Goodenberger, McKinsey L., Brittany C. Thomas, and Teresa Kruisselbrink (eds), Practical Genetic Counseling for the Laboratory (New York, 2017; online edn, Oxford Academic, 1 Mar. 2017), https://doi.org/10.1093/med/9780190604929.001.0001.

Ian D. Young. (2007). Introduction to Risk Calculation in Genetic Counseling: Vol. 3rd ed. Oxford University Press.

Mathiesen, Amber, and Kali Roy. Foundations of Perinatal Genetic Counseling : A Guide for Counselors  / Amber Mathiesen, Kali Roy. New York, NY: Oxford University Press, 2018. Print.