Posts Tagged ‘Understanding Research’

“Viva La Evidence” – A Great Lighthearted Parody on Evidence Based Medicine

December 24th, 2013 by avatar


Photo: Viva La Evidence video by J. MCormack

Photo: Viva La Evidence video by J. MCormack

Lamaze International and Science & Sensibility are all about supporting and promoting evidence based practice and evidence based health care. Here at Science & Sensibility, our mission is to help both professionals and consumers understand research and to encourage readers to view studies with a critical eye.   We believe that when best practice maternal/infant care is based on evidence and solid research, mothers and babies benefit.  Birth professionals have a responsibility to understand research and be able to share best practice information with the families we work with.

Today, I would like to share a fun music video parody “Viva La Evidence” set to Cold Play’s Viva La Vida (a song both my teenagers recognized and commented on, until they realized this video’s lyrics were a bit different!) created by James McCormack, PhD.  Dr. McCormack is on the faculty at the University of British Columbia and in cooperation with Mike Kolber, MD, creates informative and very funny podcasts and videos through  Therapeutics Education Collaboration. The purpose of the TEC is to “provide physicians, pharmacists, nurses, nurse practitioners, physician assistants, naturopathic physicians, other health professionals, and the public with current, evidence-based, practical and relevant information on rational drug therapy.” All done with a healthy dose of humor!

Science & Sensibility has had lots of posts on our blog over the years that can help birth professionals to better understand research and evaluate studies for themselves with a critical eye.  We have also had wonderful contributors who have explained research studies and helped us to understand them better.  I am very appreciative for all the time and energy freely shared by the professionals who have written for this blog.

Here is some more information for you to have at your fingertips:

Becoming a Critical Reader: An introduction

Becoming a Critical Reader: Bias, Bias Everywhere!

Becoming a Critical Reader: Journal papers that aren’t studies

Becoming a Critical Reader: Questions to ask about systemic reviews and meta-analyses

Becoming a Critical Reader: Questions to Ask About Literature Reviews

Becoming a Critical Reader: Questions to Ask About Qualitative Research

Becoming a Critical Reader: Questions to Ask About Quantitative Research

Becoming a Critical Reader: Questions to Ask About Original Research

Becoming a Critical Reader: The Five Basic Questions

Understanding Methodologies: Why Methods Matter

Understanding Methodology: The Basics of Sampling

Understanding Methodology: Elements of Experimental Design

Tracking Down Studies: Going Around Obstacles

Tracking Tools: Follow the Herd

Basic Tracking Skills: How to find what you’re hunting for

Hunting Grounds: Where to look for studies

Happy 20th Anniversary to the Cochrane Collaboration!

A great video tutorial by Rebecca Dekker on how to search using the Cochrane Library

(Remember, Lamaze International members get free access to the Cochrane Collaboration as a member benefit.)

Enjoy the video parody, a bit of lightheartedness for us all during the holiday season.

Childbirth Education, Evidence Based Medicine, Research, Series: Understanding Methodologies , , , , , , ,

Understanding Methodology: Elements of Experimental Design

July 2nd, 2013 by avatar

In this third series on Understanding Research, we will take a basic look at methodologies that are used in research. Both qualitative and quantitative approaches will be explored, with discussion on the reasons different approaches might be used and the strengths and weaknesses of each. Hopefully this will help you to better understand why the methodologies matter and what you should consider as you read research that helps you to teach and share evidence-based information on topics of maternal and infant health. The first post in the Understanding Methodology can be found here.  The second, here. Today we discuss the elements of experimental design. If you would like to review what Andrea has discussed on the blog in the past, to refresh your understanding, please click here. – Sharon Muza, Community Manager


Experimental research: The Pre- and Post-test design


Now that we are ready to talk about specific methods, we’ll start with one of the most basic of the experimental designs. The researcher wants to know if a specific thing works. Could be a drug, a procedure, an educational program, or any number of things. Researchers call this thing a variable, and it could be a treatment, an educational program, or a new product. The variable the researcher is testing is the independent variable, or the one the researcher is manipulating. The dependant variables are the outcomes the researcher is looking at.

For the sake of this discussion, let’s say it is a new breastfeeding program that a hospital is implementing. This program would send a lactation consultant to the bedside of every mom who delivers in the hospital within 24 hours of the baby’s birth. The program is the independent variable.

The hospital will want to choose several measures that might indicate the success of the program. These are the dependent variables, or outcome measures. In our example, the hospital might want to document the breastfeeding rates, number of moms who complain of nipple soreness, and the weights of babies for 3 months just before beginning the program. This would give them a baseline number for what is happening before introducing the program. Then after successfully implementing the program, they would measure the same things for three months afterward, and see if the outcomes are any different.

The hospital could then compare the two rates to see if the new program improved breastfeeding outcomes.

This basic format can give good results, but there are some issues. One threat to the validity of the study is that other things could happen over the course of the study that could impact breastfeeding rates. If, for example, a new store selling breastfeeding items opened up nearby and the owner offered free breastfeeding courses that were very popular, that could have some effect on breastfeeding successes as well, making the hospital program look better than it really is.

Most researchers will add a control group to this design in order to try and avoid issues of events that could confound the results. In this example, the hospital might do the pretest as before, monitoring the data for 3 months before introducing the new lactation program, then offer the program to HALF the women birthing at the hospital. The women should randomly be divided between those who receive the program and those who receive the usual support provided before the program began. It would look more like this:

In this way of doing the study, any event that happens along that way that could confound the results would likely happen to both groups, and there is a greater chance that the difference between the two groups is in fact due to the new lactation program.

Ethically, researchers cannot always let the control group have no intervention. For example, if you wanted to do a study on the effectiveness of a new way of resuscitating newborns, you cannot ethically let the control group go without any treatment. In these cases, researchers will test the NEW treatment against the current way of doing things.

You could even have more than one experimental group. Maybe the hospital could have a group that gets no lactation program, a group that gets the program on request only, and a group that always gets the lactation program. Knowing if the program works just as well when it is available on request might make a difference in how the hospital implements the program.

The more groups you have, the larger the sample size you need to get significant results, so researchers will make the decision very carefully, keeping in mind logistic and budgetary concerns as well as what they would like to discover with their research.

When doing a study with a control or comparison group, researchers need to be able to show that there are not any significant differences between the two groups that could account for the difference. You’ll often find tables like this one (O’Sullivan, 2009) showing the demographic makeup of the two groups.

While it would be nice to have identical groups, life is not usually that perfect and the groups will likely have some differences. The chart above shows two groups that are not identical, but are pretty close in the characteristics listed.

Many of the studies you see will have some variation on this basic design. We’ll talk further about specific experimental designs in the next segment of our series.


Creswell, J. (2009) Research Design: Qualitative, Quantitative and Mixed Methods Approaches. (3rd edition)

Greenhalgh, T. () How to Read a Paper: The Basics of Evidence-Based Medicine (4th ed.).

O’Sullivan, G., Liu, B., Hart, D., Seed, P. & Shennan, A. (2009) Effect of food intake during labour on obstetric outcome: randomised controlled trial. BMJ  338:b784. doi:10.1136/bmj.b784.

Rees, C. (2003). Introduction to Research for Midwives (2nd ed.). London. Elsevier Limited.



Childbirth Education, Evidence Based Medicine, Guest Posts, New Research, Research, Series: Understanding Methodologies , , , ,

Understanding Methodologies: Why Methods Matter

June 25th, 2013 by avatar
I am delighted to welcome regular contributor, Andrea Lythgoe back to Science & Sensibility.  In this third series on Understanding Research, we will take a basic look at methodologies that are used in research. Both qualitative and quantitative approaches will be explored, with discussion on the reasons different approaches might be used and the strengths and weaknesses of each. Hopefully this will help you to better understand why the methodologies matter and what you should consider as you read research that helps you to teach and share evidence-based information on topics of maternal and infant health.  If you would like to review what Andrea has discussed on the blog in the past, to refresh your understanding, please click here. – Sharon Muza, Community Manager

© http://flic.kr/p/bt8JGF

We’ve all heard the saying that the randomized controlled trial is the “gold standard” method of conducting a research study. What does that mean? And if the randomized controlled trial is so good, why does anyone ever do studies any other way?

In this series on understanding research, we will look at the various methodologies for conducting studies, why studies are done with the various different methodologies, and we’ll discuss some of the strengths and weaknesses of each.

In general, research methodologies can be broken down into two major categories: quantitative and qualitative. Quantitative research seeks to use statistical techniques to clearly show that certain outcomes happen because of certain variables. Qualitative research seeks to understand, find common themes, and explain the way people and societies think, behave and function. More and more studies are taking a mixed approach, using both qualitative and quantitative approaches in the same study.

One common theme that drives the way researchers choose to conduct their methodology is the idea of validity. A well done study will be done in a way that there isn’t any problem with the validity. There are three main kinds of validity that have to do with methodology:

Construct validity is the idea that the study really does measure, describe, or explain what it claims to. This is the main area where the researcher is carefully considering methodology in order to avoid problems. Amy Romano posted a discussion of a study where she challenged the construct validity here,  where she raised the question about whether microtrauma was a valid measure of perineal function.

Internal Validity is the accuracy of the study in showing clearly that the conclusions are connected. Researchers sometimes go to great lengths to try and avoid problems with internal validity.  Control groups, blinded studies, and observational studies where the researcher does not identify themselves are all ways that researchers try to create greater internal validity. A classic example of this is a study that uses a pretest and a posttest to determine how effective an education program is. If you give the same test before and after, the students will know ahead of time which questions are on the test, and are more likely to remember those answers for the posttest, artificially inflating the measured effectiveness.

External validity describes how easily the study can be applied into practice. Because readers or other researchers may be using the results in different places, times and populations, the results may or may not be applicable. This is why studies need to carefully describe the included population and settings, and readers need to carefully consider if the results are applicable to their practice. Essentially, if a study has external validity, you would get the same results if you ran the study again in a different population or different time.

As a side note, there is another kind of validity, statistical validity, that has more to do with the statistical analysis afterward than the methodology we will cover in this series. It questions whether the statistical techniques used were appropriate and accurately support the conclusions. While researchers do generally plan for their analysis when designing studies, we’ll be talking more about statistics in a future Understanding Research series.

When a researcher sets up a new research study, they need to choose the methodology that creates the most validity within the constraints of ethics, expenses, and other practicalities. Understanding the basics of why different methodologies may have been chosen can help you understand the strengths and weaknesses of the studies better.


Creswell, J. (2009) Research Design: Qualitative, Quantitative and Mixed Methods Approaches. (3rd Edition) Sage Publications, Thousand Oaks, CA

Greenhalgh, T. (2010) How to Read a Paper: The Basics of Evidence-Based Medicine (4th ed.).

Rees, C. (2003). Introduction to Research for Midwives (2nd ed.). London. Elsevier Limited.



Childbirth Education, Films about Pregnancy, Guest Posts, Research, Series: Understanding Methodologies , , , , , ,

Support Needs of Mothers Who Experience Postpartum Psychosis and Their Partners: A Qualitative Research Review

July 31st, 2012 by avatar

This is part one of a two part series on the support needs of women who experience postpartum psychosis, and their partners and is written by regular contributor Walker Karraa.  Part two will run next week. – SM

Support Needs of Mothers Who Experience Postpartum Psychosis and Their Partners (Doucet, Letourneau, & Blackmore, 2012), is a study published in the Journal of Obstetric, Gynecological & Neonatal Nursing (JOGNN) has offering new qualitative data regarding the support needs of mothers who experience postpartum psychosis (PP).

It is important to note that this is the first published study looking directly at the support needs, preferences, and access to support for women who have experienced PP and their partners, and the importance of qualitative research in deepening our understanding of maternal health.

Creative Commons Image: Pamela Machado

As you know, qualitative research attempts to make explicit the lived experience of a phenomenon. Rather than quantifying an objective symptom in empirical methods and deducing what an experience is through external measurements, qualitative research methods put the lived experience of the individual center stage, and develop inductive strategies for learning about the human experience. In this study, for example, the authors use semi-structured interviews from mothers and partners to find themes in the content that may suggest more effective prevention and treatment strategies. Listening to mothers and using their subjective experience of PP and the needs they had in recovery offered a quality of information (data) that traditional quantitative data does not, and could not—by the very nature of its design and purpose. We cannot measure motherhood. But we can learn to listen to motherhood through multiple perspectives in order to learn its meanings and mitigate our advocacy.

Postpartum Psychosis: Some Background               


Postpartum psychosis affects 1-2 women per 1,000 births globally, and while rare, it is an extremely severe postpartum mood disorder (Kendell, Chalmers, & Platz, 1987; Munk-Olsen, Laursen, Pedersen, Mors, & Mortensen, 2006). This most debilitating illness occurs in all cultures, affecting mothers across socioeconomic, ethnic, and religious communities (Kumar, 1994).


Symptoms of postpartum psychosis are sudden in onset, usually occurring within 48 hours to 2 weeks following birth. PP represents “psychiatric emergency and warrants hospitalization” (Beck & Driscoll, 2009, p. 47). If left untreated, some dire potential outcomes include:

  • 5% of women who experience PP commit suicide (Appleby, Mortensen, & Faragher, 1998; Knopps, 1993).
  • 2%-4% are at risk of harming their infants (Knopps, 1993; Spinelli, 2004).
  • PP has a 90% recurrence rate (Kendell et al., 1987).

According to the American Psychiatric Association (APA, 2000, p. 332), symptoms of PP include:delusions, hallucinations, disorganized speech, and grossly disorganized or catatonic behavior occurring within 4 weeks following childbirth, and that is not accounted for by other medical conditions, substance use, or mood disorders with psychotic features. Current research demonstrates that contrary to popular beliefs, PP is often the result of either bipolar disorder or major depressive disorder with psychotic features, and there is little frequency of PP caused by reactive psychosis or schizophrenia (McGorry & Connell, 1990).

Study Review

The goal of the recent JOGNN study Support Needs of Mothers Who Experience Postpartum Psychosis and Their Partners (Doucet, Letourneau, & Blackmore, 2012) was: “To explore the perceived support needs and preferences of women with postpartum psychosis and their partners” (p.236).  A multisite, exploratory, qualitative descriptive design was implemented using a purposive sample of nine mothers (Canada, n = 7, United States, n = 2) and eight fathers (Canada, n = 7, United States, n = 1). Data were collected through one-on-one, in-depth, semi-structured, interviews lasting 45-120 minutes. Partners were interviewed separately. All interviews were audio-recorded and transcribed verbatim, and then analyzed using inductive thematic analysis in six phases based on the methods of Braun and Clarke (2006), thematic content regarding support for mothers emerged in the categories of (a) support needs; (b) support preferences; (c) accessibility to support; and (d) barriers to support.

Mothers’ Support Needs

Instrumental, Informational, and Emotional

Doucet et al., (2012) concluded that “all mothers reported the need for instrumental, informational, emotional, and affirmational support” (p. 238. Bottom line, the mothers needed good information about their illness, good information about taking care of an infant, and physical in home assistance.

Generic support of parenting needs included information on caring for newborn, and physical assistance with house cleaning and infant care. Following hospitalization for PP, the majority of participants described wanting 24-hour support at home. Some wanted help with physical needs of meal preparation, bathing, and assistance with confusion, disorientation, memory loss. Help with night feeding, holding, etc. were significant, as one mother noted:

It was helpful having people come over and play with him and take care of him, and if I am in that manic state I can just carry on and get it out of my system. (p.239)

Mothers reported needing reassurance that the cause of their illness was biological, that they would recover:

The turning point was when I talked to someone who had gone through the exact same thing as me. The fact that she turned out okay and went on to have a happy good life with other kids was reassurance that I could get through this. (p. 238)

Women also wanted specific information on PP including:

  • treatment options
  • medication safety when breastfeeding
  • long term prognosis
  • risk of relapse with future pregnancies
  • community support

Mothers’ Support Preferences

Mothers wanted clinical information from professionals, and emotional, affirmational, and physical support from informal networks—such as peers, partners, and families.  There was a “strong preference” (p. 239) to receive physical help with baby from family, rather than formal sources such as in home nurses, etc.

All women wanted one-to-one, face-to-face support from a professional, at least once a week immediately after symptoms began. Once symptoms had improved, mothers reported preferring group support in face-to-face format, with mothers who had experienced postpartum mental health issues, and facilitated by someone with experience in PP, such as a professional, or a woman who had recovered from PP. They wanted to bring their babies to group sessions.

Access to Support

All mothers obtained access to a general psychiatric unit for immediate support with symptoms, but it is important to note they preferred a unit that specialized in postpartum mood disorders.

They felt they did not belong on a general unit, and did not receive specialized support. Most disturbingly, none of the women were able to see their infants, as is standard protocol in general psychiatric units, and found this extremely painful and hindered their recovery.

Barriers to Recovery

Barriers to recovery for the mothers in the study included the perception of health care providers as too clinical, uncaring, and having restricted their access to families. Isolation in the hospital, not seeing care provider, or feeling rushed in the appointment were also reported care-provider barriers. Family lack of knowledge about PP was reported as a barrier to recovery. One participant shared:

If my husband had a support group for new fathers to deal with a psychotic wife, it would have changed everything. He would have been far more compassionate had he known about my illness. He needed tools to deal with a mentally ill wife. (p. 241)

Finally, mothers in the study identified the lack of education regarding the differences between postpartum psychosis and other postpartum mood and anxiety disorders in family, peers and friends as a significant barrier to their own recovery. I think it is fair to offer considerations in approaching the topic so that together we will build a dialogue of difference, a conversation of consideration for how childbirth professionals process perinatal psychiatric illness, and learn to overcome fear through knowing.

In the next submission the findings from the fathers and partners will be reviewed, and considerations for childbirth professionals will be discussed.


Appleby, L., Mortensen, P., & Faragher, E. (1998). Suicide and other causes of mortality after post-partum psychiatric admission. British Journal of Psychiatry, 173, 209-211.

Beck, C. & Driscoll, J. (2006). Postpartum mood and anxiety disorders: A clinician’s guide. Sudbury, MA: Jones and Bartlett.

Braun, V., & Clarke, V. (2006). Using thematic analysis in psychology. Qualitative Research in Psychology, 3, 77-101. doi:10.191/1478088706qp063oa

Doucet, S., Letourneau, N., & Blackmore, E. R. (2012). Support needs of mothers who experience postpartum psychosis and their partners. Journal of Obstetric, Gynecological & Neonatal Nursing, 41(2), 236-245.

Kendell, R., Chalmers, J., & Platz, C. (1987). Epidemiology of puerperal psychosis. British Journal of Psychiatry, 150, 662-673.

Knopps, G. (1993). Postpartum mood disorders: A startling contrast to the joy of birth. Postgraduate Medicine, 93, 103-116.

Kumar, R. (1994). Postnatal mental illness: A transcultural perspective. Social Psychiatry and Psychiatric Epidemiology, 29, 250-264. doi:10.1007/BF00802048

McGorry, P., & Connell, S. (1990). The nosology and prognosis of puerperal psychosis: A review. Comprehensive Psychiatry, 31, 519-534.

Munk-Olsen, T., Laursen, T., Pederson, C., Mors, O., & Mortensen, P. (2006). New parents and mental disorders: A population-based register study. Journal of the American Medical Association, 296(21), 2582-2589. doi:10.1001/jama.296.21.2582

Spinelli, M. (2004). Maternal infanticide associated with mental illness: Prevention and promise of saved lives. American Journal of Psychiatry, 161(9), 1548-1557.

About Walker Karraa

Regular contributor Walker Karraa is currently the President of PATTCh, an organization dedicated to the Prevention and Treatment of Traumatic Childbirth. Walker is a doctoral student at Institute of Transpersonal Psychology, a certified birth doula, freelance writer, and maternal mental health advocate.  She holds an MA degree in Clinical Psychology from Antioch University Seattle, and a BA and MFA degree in dance from UCLA.  Walker is a contributor to the Lamaze sites, www.givingbirthwithconfidence.org and www.scienceandsensibility.com.  She lives in Sherman Oaks, California with her husband, and two children.

Depression, Maternal Mental Health, Maternal Mortality, Maternal Mortality Rate, New Research, Perinatal Mood Disorders, Postpartum Depression, Postparum depression, Pregnancy Complications, Prenatal Illness, Uncategorized , , , , , , , , ,

Epidural Analgesia—a delicate dance between its positive role and unwanted side effects (Part Three)

March 4th, 2011 by avatar

[Editor’s Note: This is the last in a series of three posts by Dr. Michael Klein regarding the research behind risks, benefits and realities of epidural analgesia.  To read Dr. Klein’s first two posts, go here and here.]

Not all women are alike in labour and delivery:
Because the experience of labour pain, including severity, tolerance and contraction patterns, differs greatly among women, so does their ability to cope with the labour process.  In consequence, some women feel the need to receive epidural analgesia prior to the onset of active labour.  In some cases, the use of an early epidural will relax a woman enough to help her labour progress to the active phase and thereby lead to less subsequent medical interventions.  However, if used early without specific indications, a woman may find herself exposed to a larger range of interventions, including a caesarean birth.

Dealing with the reality of the labour ward:
Given this paradox and the severity of some of the side-effects of epidural analgesia, it is time to be honest about the full effects of this excellent technology: there is no such thing as a side-effect. There are only effects, some of which we like and some of which we don’t. When epidurals are used specifically to problem-solve, the risks of complications and other interventions are in fact reduced. When used routinely and mindlessly, epidural analgesia increases problems and adverse outcomes. Women need to be fully informed of this before agreeing to an epidural. Today, women are usually only informed of the direct consequences of epidural analgesia, such as a headache or even very rare neurological complications, but they are not often informed of the consequences that can occur if epidurals are given routinely or too early. They are rarely told about the potential deleterious effects of an epidural on the woman’s labour, nor the cascade of other interventions that might ensue. They are unlikely to be informed that an epidural will increase the demand on their nurse to pay greater attention to the technology and in consequence provide less hands-on support for the labouring woman. They are unlikely to be made aware of an epidural’s purported interference with the initial success of implementing breastfeeding following the baby’s birth.

Epidural analgesia is clearly an effective form of pain relief but it can also have less desirable consequences. Women need to be accurately and completely informed of their choices for pain relief in labour before they can provide their true consent. No matter how well intended, epidural analgesia increases the likelihood that women will have a variety of other interventions, especially if the epidural is given without specific medical indication. Women need to know that when epidural analgesia is given before the active phase of labour, it more than doubles the probability of a cesarean section.

The importance of timing and setting:
Women also need to be reassured that when epidural analgesia is given in the active phase of labour, it does not increase the cesarean section rate. This may motivate women to use other pain relief modalities and methods to help them, if possible, get to the active phase before requesting an epidural.

Readers of the literature also need to remember the importance of setting when reading about the research on epidural analgesia and any other interventions. All the statistics and outcomes that have been discussed here are in fact specific to the setting or environment from which the individual study or meta-analysis emanate. It is important to remember that adverse effects of epidural analgesia can be mitigated, especially if the setting generally limits the use of interventions. It appears, for example that in settings with low cesarean section rates (below 10%), even early epidurals do not increase the cesarean section rate,(21) but in more typical settings where cesarean section rates are higher than 20%, it does. This illustrates a general principle: For all studies, randomized or not, the reader needs to ask the question: do the caregivers in the studies practice the way that I do? If they do, the study may apply but if not, they may not.

The bottom line is that epidural analgesia has completely transformed birth. This massive change in the way that many women receive care in labour and birth has been based on a technique that, when used selectively and as a back-up tool or second line approach, is an important and valuable technique, among the many ways of assisting women with labour and birth. However, when used routinely as a first line agent, epidural analgesia can create problems that could have been avoided. Our Canadian National Study of the Attitudes and Beliefs of Maternity Care Providers has illuminated the very different ways that different disciplines view birth. (22) Most Canadian younger obstetricians (23)and women approaching their first birth (24) do not even know that epidural analgesia interferes with labour. The older generation of obstetricians knows that it does. They have experienced the changes related to epidural analgesia availability and usage during their many years in practice before and after the common use of epidural analgesia. It is time we told the truth about epidural analgesia – to colleagues and women – and engaged in a truly informed decision-making discussion with women about the optimal use of epidural analgesia.

References for this entire series of posts can be found here: References _ michael klein post

Post by:  Michael C. Klein, MD, CCFP, FAAP(Neonatal-Perinatal),FCFP, ABFP
Emeritus Professor of Family Practice and Pediatrics
University of British Columbia
Senior Scientist Emeritus
Centre Developmental Neuroscience and Child Health
Child and Family Research Institute
4500 Oak Street
Vancouver, V6H 3N1
Tel: 604-875-2000 ext 5078
Fax: 604-875-3569

Epidural Analgesia, Evidence Based Medicine, Practice Guidelines, Research, Science & Sensibility, Uncategorized , , , , , , , , , , , ,

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