Academic Writing: Scientific Writing--IMR(a)D structure

Know what IMR(a)D stands for? Need a refresher on how to write an empirical research paper? This post describes some basics to scientific writing.

Scientific Writing

From the post on overall structure, we learned that Academic Writing is a particular genre of writing. However, inside Academic Writing there are also other sub-genres such as essays or scientific reports. This post is about scientific reports, so let's examine some key differences between scientific reports and essays.

Which paragraph is from a scientific report? Which is from an essay? How do you know?

For practical purposes, everyone knows what a lobster is. As usual, though, there’s much more to know than most of us care about—it’s all a matter of what your interests are. Taxonomically speaking, a lobster is a marine crustacean of the family Homaridae, characterized by five pairs of jointed legs, the first pair terminating in large pincerish claws used for subduing prey. Like many other species of benthic carnivore, lobsters are both hunters and scavengers. They have stalked eyes, gills on their legs, and antennae. There are dozens of different kinds worldwide, of which the relevant species here is the Maine lobster, Homarus americanus. The name “lobster” comes from the Old English loppestre, which is thought to be a corrupt form of the Latin word for locust combined with the Old English loppe, which meant spider.

The Ancient Egyptians referred to celestial events indirectly [1–4] by relating them to mythological events. Many prognoses in the Calendars of Lucky and Unlucky Days have been connected to astronomical observations [1, 5–7]. Such connections between astronomical events and prognosis texts have been uncovered in most cases only for individual days [6, 8,9]. The PM = 29.6 days period of the Moon has been discovered in CC [10]. We have claimed that this document also contains the PA = 2.85 days period of the eclipsing binary Algol [11]. However, it not a straightforward task to identify those indirect mythological references that are influenced by Algol in CC. Here we present a statistical analysis that reveals which CC prognosis texts describe Algol’s regular variability.

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A Reminder on Academic Structure

Before  we continue on, it's also important to remind ourselves of the overall structure of Academic Writing. Even though Scientific Writing is a particular sub-genre of Academic Writing, it still follows the overall structure we discussed earlier, it just adds some new rules of its own!

If you need a reminder, return to our post about the overall structure of academic writing.

Can you complete the rules below to remind ourselves of the overall structure of academic writing?

Academic Writing follows a _________ pattern at both the paragraph level and at the overall level.  

Academic paragraphs begin with a ________ sentence that unifies an entire paragraph. 

Academic Writing follows a rule of 3's: first, ________ the idea; second, _______ the idea; and third, _______ to the idea and end the writing. 

Check Answers. 

IMR(a)D Structure

Okay, now that we have the general idea of Academic Writing in our minds, let's focus on a particular type of Academic Writing: Scientific reports.

Scientific reports (in particular, empirical research reports) generally follow the IMR(a)D structure (read it as "I'm rad" to remember it more easily). IMR(a)D stands for

• Introduction
• Methods / Methodology
• Results
• (and)
• Discussion / Conclusion

These sections are clearly labeled in a report (i.e. each section begins with a new subheading). For examples of what this design looks like, visit this website that provides free scientific reports to the general public.

http://journals.plos.org/plosone/

So, what information can be found in each of these sections?

The Introduction 

Let's examine an example introduction and answer a few questions. 

Where does the example introduction

• Highlight the relevance of the research?
• Identify the problem or gap that exists in the field?
• Describe the overall aim of the paper?
• Outline the paper’s structure?

Example introduction:

Research over the past decade has argued that musical preferences reflect explicit characteristics such as age, personality, and values [3–6]. Indeed, findings across studies and geographic regions have converged to show that the Big Five personality traits are consistently linked to preferences [6–12]. For example, people who are open to new experiences tend to prefer music from the blues, jazz, classical, and folk genres, and people who are extraverted and agreeable tend to prefer music from the pop, soundtrack, religious, soul, funk, electronic, and dance genres [13].

Though these findings are consistent across studies, what is also consistent is that the results have small effect sizes (r < .30) when compared to benchmarks used in other psychological research [14]. This raises the question of whether there are additional psychological mechanisms that might account for individual differences in musical preferences. In this article we build on previous research by examining two dimensions that may be linked musical preferences: empathy and systemizing.

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The Methods / Methodology

This section is sometimes called the "Methods" or "Methodology". The label merely depends on the scientific field.

Generally, in this section the authors describe how they performed their experiment, so that others are able to repeat the experiment. In order to write clearly enough so that others can repeat the experiment, this section usually fulfills the following functions:

• restates the purpose of the research
• sources the materials/equipment used
• describes necessary background information
• provides specific & precise details about materials and methods
• justifies choices made by the authors within the experiment
• indicates that appropriate care was taken
• relates the materials and methods to other studies
• indicates where problems occurred

So, let's look at a few examples of paragraphs from a Methods section.

Which function or functions are found in the example paragraph below?

We tested a total of 14 subjects (4 females, 10 males; age = 26.4 ± 6.0 years, body mass = 71.1 ± 12.8 kg; mean ± standard deviation). The University of Michigan Health Sciences and Behavioral Sciences Institutional Review Board approved the study, and all subjects gave written informed consent. 

Each subject rode under five experimental conditions distinguished by pedaling cadence, established via a metronome, and bicycle ‘speed’ controlled via gearing (the method for measuring speed is given in Instrumentation). The five conditions were executed in the following order: 1) cadence 80 rpm and speed 5.08 m/s, 2) cadence 80 rpm and speed 7.19 m/s, 3) cadence 80 rpm and speed 6.98 m/s, 4) cadence 80 rpm and speed 2.58 m/s, and 5) cadence 40 rpm and speed 1.29 m/s. Each subject rode for a minimum of 2 minutes in each condition until s/he could ride for at least 30 seconds without touching a static support surface with hand or foot.

Check Answers.   

The Results

Some scientific fields include the Results with the Discussion. For now, we're going to look at them separately.

Below, I've included a table that lists the different "functions" typically found in the Results section and an example paragraph from a scientific report. Are you able to match the functions of the paragraph to the examples? The first one has been modeled for you.

Which functions occur in the example?

Example 1

For a perfectly balanced rider-bicycle system traveling in a straight line, we would expect yCOM= yCOP. However, as in human standing, yCOM ≠ yCOP during actual bicycle riding. Instead, we expect the positions of the centers of mass and pressure to co-vary, and that is what we observed (as shown in Fig 4 for a typical 40 second period).

Function	Example 1	Example 2	Example 3
Mentioning the research aim
Mentioning the methodology
Mentioning a general overview of the results	Yes
inviting the reader to view results	Yes
Specifying key results in detail, with or without explanations
Comparing the results with other studies
Comparing the results to model predictions	Yes
Mentioning problems with the results
Mentioning possible implications of the results

Example 2

We quantified balance performance by calculating the cross-correlation (R2) of the center of mass location (yCOM) to the center of pressure location (yCOP). For a perfectly balanced bicycle, R2 would be equal to one (1.0), but for bicycle riding, we observe values less than one (Fig 5).

Example 3

The lateral positions of the center of mass and center of pressure were highly correlated during bicycle riding (Fig 5). Our results did not indicate a significant effect of rider type (F = 0.041, p = 0.841), but did show significant effects for both speed (F = 29.113, p < 0.001) and the rider type × speed interaction (F = 14.843, p < 0.001). All riders demonstrated high correlation at low speeds, but as speed increased, cyclists maintained a higher correlation than non-cyclists…

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The Discussion / Conclusion

Some scientific fields include the Discussion and the Conclusion together. Some don't have a Conclusion and end with the Discussion section. And some don't have a separate Discussion section altogether; instead, they combine the Results and the Discussion section together. For now, we're going to examine The Discussion by itself and as the final section of writing in a research report.

Typically, the Discussion section describes

1. the overall indication(s) of the data
2. the limitations of the study 
3. the Relationship to previous studies

Let's examine an example Discussion section and match the questions below to the paragraph that answers the question.

Questions:

1. What was analyzed and what were the main findings?
2. How can these results be interpreted?
3. How do these results relate to previous research?

Example Discussion:

Read the Discussion by clicking here:

Kellermann, A. L., Rivara, F. P., Rushforth, N. B., Banton, J. G., Reay, D. T., Francisco, J. T., Somes, G. (1993). Gun Ownership as a Risk Factor for Homicide in the Home. New England Journal of Medicine N Engl J Med, 329(15), 1084-1091. Retrieved March 30, 2016, from http://www.nejm.org/doi/full/10.1056/NEJM199310073291506#t=articleDiscussion

Example answer:
The following text is the first sentence of the first paragraph from the example Discussion:

Although firearms are often kept in homes for personal protection, this study shows that the practice is counterproductive. Our data indicate...

We know from this first sentence what was analyzed (firearms for home use) and some of the main findings  (study shows...). Therefore, the first paragraph answers the first question and gives us an overall indication of the data. Now, can you match the rest of the paragraphs to each question?

Which question or questions do the rest of the paragraphs answer? You only need to read the first 1 or 2 sentences in each paragraph to match the paragraph to the question. 

 

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Final Thoughts

Now that we have a general understanding of the structure of Scientific Writing, reading Scientific Writing should be easier. If we want to find what the authors predicted, there's no reason to read the Methodology or Discussion section: the Introduction has that information! If we want to find out how the authors performed their experiment, we can skip straight to the Methodology section.  And what's more important is that within these sections the paragraphs themselves follow general Academic Structure, which means we can read reports by skimming topic sentences in order to quickly locate what we're looking for.

Also remember, if you are writing in a particular field (e.g. social sciences, not physical science), then it's best to read and examine other scientific papers from that particular field. This post provides a general overview of the typical structure and content, but of course some things may vary slightly from field to field.

We can continue to examine examples by visiting http://journals.plos.org/plosone/ or other academic journals, and improve our Scientific Writing knowledge through reading what others have written.

If you have any other advice for scientific writing, feel free to leave it in the comments below!


References

Greenberg DM, Baron-Cohen S, Stillwell DJ, Kosinski M, Rentfrow PJ (2015) Musical Preferences are Linked to Cognitive Styles. PLoS ONE 10(7): e0131151.doi: 10.1371/journal.pone.0131151

Cain SM, Ashton-Miller JA, Perkins NC (2016) On the Skill of Balancing While Riding a Bicycle. PLoS ONE 11(2): e0149340. doi: 10.1371/journal.pone.0149340

Kellermann, A. L., Rivara, F. P., Rushforth, N. B., Banton, J. G., Reay, D. T., Francisco, J. T., Somes, G. (1993). Gun Ownership as a Risk Factor for Homicide in the Home. New England Journal of Medicine N Engl J Med, 329(15), 1084-1091. Retrieved March 30, 2016, from http://www.nejm.org/doi/full/10.1056/NEJM199310073291506#t=abstract