Dazzled by Science! Part Two: Quantitative vs. Qualitative?

Lana Kaiser MD, DVM

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October 14, 2021

Last time we talked about scientific manuscripts, their parts, and the process of getting something published. Now we are going to talk about different kinds of research and the different ways of categorizing scientific studies. (You can read the first article in this series here.)

We could classify research by the discipline – so physiology, pharmacology, psychology, geriatric medicine, veterinary behavior, genetics etc. While that does provide some information, I am not certain it is useful, particularly as multidisciplinary studies (those that involve scientists from different areas of expertise) are now quite common.

Maybe what is more useful is — quantitative vs qualitative research. Qualitative research involves collecting and interpreting non-numerical data (think “quality”) and focuses on words and meaning.
Focus groups, observation, interviews, and written recordings are methods of collecting qualitative data.

Quantitative research involves numbers and identifying relationships among variables (think “quantity”). Numerical data can be obtained from experiments, data bases, and surveys. Let’s look at these in a little more detail.

QUALITATIVE RESEARCH

Qualitative research is used primarily in social science, psychology, nursing, economics, education, criminal justice, public health, health care, and marketing, but can be used in behavior and welfare studies. Qualitative research is the process of collecting and interpreting non-numerical data, generally written or spoken narratives, to gain an understanding of a particular event, person, or group. The purpose of qualitative research is to gain insight or understanding of “lived experience” (phenomenological research) or examine a culture (ethnographic research). The goal is to find theories that help explain a particular phenomenon – to describe a topic more than measure it. Focus groups are used to understand how people with common interests feel and think about an issue, a product, a service, or an idea. A trained individual asks questions and “themes” are developed  to understand various viewpoints of the topic. Ethnographic research, first developed in anthropology, gives the researcher an understanding of the culture of a group. The group can be anything – a gang, a farm, a classroom etc. The researcher is immersed in the social environment resulting in information and observations, with the goal to provide a narrative account of the culture rather than test a hypothesis.

ETHNOGRAPHIC RESEARCH

In a recent International Society for Applied Ethology webinar (10/4/2021) Maria Chen, University of British Columbia’s Animal Welfare Program, spoke about workers perception of cattle welfare in two dairies in China. Her overall goal is to work collaboratively with Chinese dairy farmers to find strategies to improving farm animal welfare. She worked with 43 employees, interviewed 13, and included her own reflections. The take away message of her talk was “cattle welfare is basically human welfare” meaning when workers are fairly compensated and valued (their needs are met) they are much more likely to treat dairy cows and calves with kindness, dignity, and respect.

“Cattle welfare is basically human welfare, meaning when workers are fairly compensated and valued (their needs are met) they are much more likely to treat dairy cows and calves with kindness, dignity, and respect.”

 

Quantitative research is different.

 

QUANTITATIVE RESEARCH

EXPERIMENTAL RESEARCH

Generally when people think of experiments they think of the mad scientist in the laboratory, but experiments can be much more nuanced. A study from Mogill’s group (Sorge et al.) asked the question “Is pain behavior blunted in the presence of people?” and answered that question in a series of elegant experiments. They used the mouse grimace scale to assess behavior and found that the pain response was blunted in the presence of human males, but not human females. Pain response was also inhibited in the presence of bedding from conspecific males (from a different cage), as well as bedding from predator species (rat, cat, dog). They then asked the question “Were the mice consciously inhibiting the pain response or was this stress induced analgesia?” Stress induced analgesia is an innate response where pain processing is suppressed in the spinal cord by descending modulatory pathways. Using immunohistochemistry they identified a greater than 50% decrease in immediate-early gene expression in the pain-processing neurons of the spinal cord dorsal horn, confirming that the mice experienced stress induced analgesia.

They concluded that “that standard laboratory practice should account for experimenter sex when investigating any phenomenon possibly affected by stress.” This study suggests that variables we generally don’t control for (sex of laboratory personnel) could influence behavior and welfare research.

Laboratory experiments are not what some think!

 

Not all experiments are performed in the laboratory. Haley et al. asked the question “Can we decrease the stress of weaning beef calves by using two stage weaning?” Weaning is a stressful event in all mammalian species, but unlike human babies, where weaning involves switching from milk to other foods, with beef calves, weaning involves both cessation of milk and separation from the dam (mother cow). Stress associated with weaning for beef calves is related to both abrupt cessation of milk and separation from the dam. Abruptly weaned calves are separated from their mother and no longer nurse milk on the same day. “Nose flaps” prevent nursing but the calf remains with the cow. The cows and calves are later separated. They assessed the calves behavior and weight at different time points. Based on behavioral data, two stage weaned calves were less distressed than calves weaned by abrupt separation, but overall calf average daily weight gain did not differ. Since weaning is one of the most stressful events in a beef calves’ life, and stress can predispose to systemic illness (pneumonia, diarrhea), this study has practical implications for people who raise beef cattle and want to improve welfare. I do note that weaning is also stressful for the cow, likely associated with both separation and distension of the mammary glands. Perhaps a more complete study would have evaluated behavior of both the cow and the calf.

Studies identifying “normal” laboratory values for a species or a breed or identifying disease biomarkers in a laboratory is generally considered “bench research.” This type of study may provide new information or be clinically useful, as it can lead to diagnostic or confirmatory tests. Immune-mediated thrombocytopenia is an auto-immune disease where the immune system misidentifies platelets as “something foreign,” and destroys them. Low platelet is the hallmark of Immune-mediated thrombocytopenia, but not all low platelet counts are the result of immune disease. Scott et al. developed and characterized an immunoradiometric assay to detect antibodies on platelets that made them appear “foreign,” resulting in their rapid destruction. The study involved platelets from 40 healthy dogs (controls) and 40 dogs with thrombocytopenia (low platelet count). Collection of platelets is a complicated process (platelets are involved in clot formation so to study platelets you don’t want to “activate them”). Radiolabeled proteins were used to identify the antibodies on platelets and to differentiate immune-mediated thrombocytopenia from other causes of low platelet count. The authors acknowledge that the primary utility of this test is in a research setting, as proper collection of sufficient non activated platelets is not commonly accomplished in routine veterinary practice. So this study provides new information that is unlikely to be clinically useful at this time.

So, how can non-scientists assess if the experiment is “good science?” A healthy dose of skepticism is always in order, but things to ask yourself: Do they have a clear hypothesis or goal? Did they ask a clear question? In these studies the question or goal was clear. In the mouse grimace scale study the answer to the first question led to another question which lead to another question – a really robust study that followed a trail created by answering the previous question. The Haley study asked a clear question about one half of a dyad, assessing behavior of the cows would have made it a complete study, but I grant that behavior studies are time consuming and labor intensive.

 

Things to ask yourself when looking for “good science”: Do they have a clear hypothesis or goal? Did they ask a clear question?

 

In the Scott study the goal was accomplished. All three studies used appropriate statistics – how do you know they are appropriate – well generally you don’t! In the dark ages, statistics were done on paper using (in the best of times) a scientific calculator. Today most data can be collected electronically and directly added to a statistical package. Statistical packages enable scientists to do a huge amount of analyses rapidly. And if they don’t find statistical significance with one analysis or model they can try another. In many cases researchers employ a statistician, who may have no familiarity with the topic or discipline, to analyze the data. So how do we evaluate the statistics? Ask yourself: Did they describe how they determined the number of replicates to see statistical significance? Do you see any flaws in the experimental design? Is it statistically significant but not biologically relevant? Do they claim “a trend towards significance” when the P value isn’t significant? Do they overstate their findings in the discussion? And look at the funding source. I am always skeptical of drug company funding of studies of their own drugs or vaccines.

Next we will continue our discussion of experimental research with a focus on surveys a research method commonly used in behavior and welfare science, and data-base research, a method frequently used in veterinary medicine.

 

Sorge RE, Martin LJ, Isbester KA, et al. Olfactory exposure to males, including men, causes stress and related analgesia in rodents Nature Methods 2014:11;629 -632 DOI:10.1038/NMETH.2935

The effects of weaning beef calves in two stages on their behavior and growth rate.   DB, Bailey DW, StookeyJM. J Anim Sci 83:2205-2214, 2015. doi: 10.2527/2005.8392205x.

Scott MA, Kaiser L, Davis JM, Schwartz KA. Development of a sensitive immunoradiometric assay for detection of platelet surface-associated immunoglobulins in thrombocytopenic dogs, Am J Vet Res 63:124-129, 2001.

Lana Kaiser MD, DVM, born in Buffalo, NY, received a BA in English from SUNY at Buffalo with plans to be a poet. She is a graduate of Michigan State College of Human Medicine, a Board Certified (Human) Internist, a cattle veterinarian, and a Emeritus Professor in the Departments of Physiology and Medicine, in the College of Human Medicine.

Trained as a biomedical researcher with a research focus on cardiovascular pathophysiology and parasitology, she is also interested in scientifically studying the interaction between humans and animals, and has published in both scientific disciplines. A 1995 graduate of the College of Veterinary Medicine, MSU she resides on a farm in Mason, MI where she raises Maine-Anjou and Red Angus cattle.

She has a mobile beef cattle practice, consults for several national agricultural entities, and has written and lectured about animal welfare, animal health, genetic defects, and human-livestock interactions at the state and national levels. She is involved in issues of animal behavior and welfare at the county, state and national level, was a founding member of MSU’s Human-Animal Bond Initiative and coordinator of MVMAs Annual Animal Welfare Conference and Animal Behavior Conference. She has been active in the MVMA Animal Welfare, Legislative, and Food Animal Practivce Committees, AABP Animal Welfare Committee, and Dean Foods Animal Welfare Advisory Council.

She enjoys clicker training her four dogs, her cow horse, and the occasional cow.