As promised, here is part 2 of Joyce's explanations in helping us understand primary research better! Did you print out the study shared and mark it all up? Let's see how well you did! (In case you hit this page first, you may wish to view Part 1 first.)
My journey to becoming a doula makes plenty of sense in retrospect, but it is a winding journey. I entered college as a pre-veterinary science major, ultimately switched to a Psychology major, hated counseling but fell in love with animal behavior research, and graduated with a BA in Psychology, Biology minor, and Biology Honors. I then entered a PhD program at the University of Nebraska-Lincoln in the Biological Sciences with the intention of becoming a research professor. I actually completed my coursework for a PhD, but cut my research short to graduate with a Masters when I decided a career in academia was no longer what I wanted. After graduation, I became a homemaker and mom when our son was born 5 months later. When he was 10 months old I completed my doula training with DONA International, and attended my first doula birth one month later. Now my husband and I have three children, I am a certified birth doula with DONA International, a Hypnobabies Childbirth Hypno-Doula, co-leader of ICAN of Lincoln (International Cesarean Awareness Network), and have attended more than 55 births. I have a passion for teaching others, empowering women and families to love one another better, birth, birds, and chocolate.
I wanted to write a guide to other doulas and to parents-to-be on how to find, read, understand, and use primary research literature. When you have found, read, and understood the research, using the information will be a highly individual decision that only the patient themselves is able to make, based on their intuition, desires, trusted counsel, and circumstances. Yesterday, I discussed how to find and read research papers in Part 1. Here in Part 2, I walk you through a short research article and talk about how to understand the paper, and how to use that information.
Here is a short example of how I read a research paper. This article is a short write-up of a conference poster session. This is preliminary research, it is probably not peer-reviewed (critiqued by other scientists in the field to make sure it is done well), and though we can still gain valuable information from it, keep in mind our knowledge can change drastically with more studies, more research, and better analysis. Go read it. Really. It's quick, you'll be back in no time! Here is the paper (if you want to and have the means, print it out and grab a pen!):
Afshar, Y; Wang, E; Mei, J; Pisarska, M; and Gregory, K. 279: Higher odds of vaginal deliveries in women who have attended childbirth education class or have a birth plan. American Journal of Obstetrics & Gynecology, 2016;214(1):S162.
Since this is such a small write-up, there is no introduction or background section, simply a research objective. Do Child Birth Education classes (CBE) and/or birth plans impact the delivery mode of those women?
Let's look at the study design. The authors looked in the past (retrospective) at a group of women all from the same period of time with similar demographic characteristics (cohort study), and give the dates and type of birthing facility. Because birth modes can differ so much between singles and multiples, the authors only looked at singleton births. They also divided the groups into all moms, and just moms having their first birth (nulliparous). Then they divided each group into moms who attended CBE, those who had a birth plan, and those who did both.
Understanding statistical analysis is a whole other ball of wax, and there is no way I can explain everything here. What you need to know is when p-values are reported (p=0.01, p>0.1, p<0.0001, etc), the smaller the p-value, the greater the effect of the variable being tested. The p-value is basically the probability that any difference between the groups is due to chance, so if the p-value is small, the difference between the groups is probably due to the different variables. There is a lot more to statistics than just understanding p-values, but there's your crash course in statistics for today.
In this study, there were over 14,000 births that were included in the analysis (met inclusion criteria). There were differences between groups of women who did and did not attend CBE and/or have a birth plan. After adjusting for these population differences, the authors found that women who had attended CBE, had a birth plan, or both, had higher odds of a vaginal delivery compared to the group who did none of those, but there was no stronger effect of doing both. This effect was true of first-time moms as well, so the impact of CBE and/or birth plans is the same no matter which birth this is for a woman. In their original poster session, the authors likely included more figures, including their logistic regression analyses, which would help us understand the relationship between the variables and their effects, but it's a simple study and we can understand the basics with the information given here.
The authors conclude that attending CBE and/or having a birth plan increase the odds of a vaginal delivery, and they state that further research is needed to understand how this works. In my opinion, given my cursory understanding of this study, I think this conclusion is sound.
The questions I have after reading this are:
Finally, the authors found a statistically significant difference in delivery mode based on CBE and/or birth plan, and with a relatively small group of women! In human research, 14,000 people is really not much. That's approximately the population of downtown St. Louis, MO. To find a statistically significant effect in a small sample size suggests that either it is due to random chance, or this is a very strong effect. I am excited to see what further research shows in this area!
In lengthier research articles, there would be a list of references. For more information on the topic and related topics, this list is where you want to start. In lengthier research articles, there would be a list of references. For more information on this and related topics, including additional studies, this list is where you want to look.
Now, how do you use this information, either for your doula or CBE clients, or for yourself? First, you must understand that research does not, and can not predict your outcome. Research is not a crystal ball, it cannot predict with certainty, in real life, who will and will not experience which outcome. In addition, the facts, found in the scientific literature, are an important piece of any decision-making process. But your intuition, your desires, the availability of options, the counsel of trusted medical caregivers, and many more variables will come together to determine the best decision for you in your circumstances. Science tries to isolate variables, to pinpoint and quantify the exact effect of one thing, which is vital for understanding how one thing affects another. But we do not live in a laboratory. Applying those results to real-life, complicated, individual healthcare decisions is something that only the patient themselves can do.
I hope that now you are better equipped to find, read, understand, and use primary research articles. Happy reading!
Joyce Dykema, MSc, CD(DONA), HCHD, became a certified birth doula in May 2012. She is also a trained Hypnobabies® Hypno-Doula, and volunteers as leadership for ICAN of Lincoln, her local chapter of the International Cesarean Awareness Network. Joyce is a woman-focused doula. While passionate about natural birth and what research shows is the best for moms and for babies, the goal she strives for with every client is for women to have empowering and positive births, as the woman defines it. In addition to her doula credentials, she holds a BA in psychology and an MS in biological sciences. She breastfeeds, uses cloth diapers, uses baby sign language, babywears, and homeschools because these choices made sense for her family; she encourages others to explore and find what makes sense for their families. Joyce and her husband have three children, and live in the Lincoln, Nebraska area.
♥ four young boys and a boy dog (offspring)