Medical Manuscript Structure: Key Sections and How to Read Them

A medical manuscript is a highly structured document with specific rules for writing and reading them. Understanding these rules is crucial for interpreting medical research effectively.

The Imaginary Study: Water and Thirsty Graduate Students

To illustrate the components of a medical manuscript, consider an imaginary study:

A young researcher hypothesizes that providing water to thirsty graduate students will decrease their thirst. After securing funding and ethical approval, 100 thirsty subjects are enrolled. 50 are randomized to drink water, while the other 50 are given an empty glass to stare at for 10 minutes. Afterward, participants rate their thirst.

The researcher finds that the water-drinking group had significantly lower thirst scores. This finding is written up and submitted to a prestigious journal, leading to a promotion, a grant, and an award.

Components of a Medical Manuscript

1. The Title

The title has one primary job: to clearly state the exposure and the outcome of the study.

• Example 1: "The diagnostic assessment of deep learning algorithms for detection of lymph node metastases in women with breast cancer."
  • Exposure: Deep learning algorithms.
  • Outcome: Detection of lymph node metastases.
• Example 2: "Ginkgo biloba extract improved cognitive and neurological functions of acute ischemic stroke: a randomized controlled trial."
  • Exposure: Ginkgo biloba extract.
  • Outcome: Cognitive and neurological function.
• Our Water Study Title: "The effects of drinking water on thirst in postgraduate students: a randomized open-label trial."
  • Exposure: Drinking water.
  • Outcome: Reduction in thirst.

2. The Abstract

The abstract is a short summary of the paper, highlighting key information. It is often accessible before a paywall. Abstracts typically include:

• Background/Importance
• Design/Methods
• Results/Outcomes
• Conclusion

3. Background/Introduction

This section explains why the study was conducted, its importance, and the context. It should clearly state the study's objective and primary hypothesis.

• Example: A study on improvisational music therapy for children with autism spectrum disorder would state its objective: "to evaluate effects of improvisational music therapy on generalized social communication skills of children with autism spectrum disorder."
• Our Water Study Background: "Water, to the extent of current knowledge, is critical for the development and sustaining of all life on Earth. We set out to determine if drinking water would reduce perceptions of thirst among a healthy but thirsty population."

4. Methods

This is a crucial section, often overlooked, that details how the study was conducted. It should provide enough information for someone to replicate the study. Key elements include:

• Study Description: Overview of the study design.
• Inclusion and Exclusion Criteria: Who was allowed in the study and who was not.
• Detailed Description of the Intervention: What was done to the participants.
• Detailed Description of the Outcome: How the outcome was measured.

• Primary Outcome: Medical studies often measure multiple things, but they should identify one primary outcome that is their main focus.

• Example: A study on blood pressure control in barbershops would detail how participants were recruited: "Field interviewers screened the clientele at participating black-owned barber shops to recruit self-identified regular patrons (greater than one haircut every six weeks for six months) who are non-Hispanic black men 35 to 79 years of age with systolic blood pressure of 140 millimeters of mercury or more."

• Our Water Study Methods: "Water was provided in 8-ounce cups (Solo Cup Company, Lake Forest, Illinois)." This level of detail allows for replication.

5. Results

This section presents the measurements and data without editorializing or hypothesizing.

• Table 1: This table traditionally describes the characteristics of the study population (e.g., age, gender, height, weight, pre-existing conditions). When reviewing Table 1, ask if the study population is representative of the people you care about or if it's a very specific group.
• Outcomes in Both Groups: The results will present the measured outcomes for all study groups.

• Figures: Visual representations of the data, such as graphs showing changes in outcomes.

• Our Water Study Results: "The average age of the grad students was 20 ± 3 years, and 60% were male. The baseline thirst score was 5 ± 1-2 in both groups. After drinking, mean thirst declined by three points in the water group compared to zero points in the control group (p-value will be discussed in a future lecture)."

6. Discussion

This is where the authors interpret their results, speculate on their meaning, and discuss implications. It's important to approach this section with a critical eye, as authors may "spin" their findings.

• Example: A study on acupuncture for chronic low back pain found that both true acupuncture and sham acupuncture provided similar benefits, significantly more than no treatment. The authors concluded that acupuncture provides "clinically relevant benefits." However, a critical reader might interpret this as the act of sticking needles, regardless of specific placement, provides subjective relief, rather than validating traditional acupuncture theories.
• Our Water Study Discussion: "Water significantly reduced perceptions of thirst among these thirsty grad students, suggesting that water should be the gold standard treatment for thirst in this population." This statement goes beyond the data, as the study only showed water reduced thirst, not that it's the gold standard compared to other potential thirst-quenchers.

Take-Home Points

• Medical manuscripts follow a set of rules.
• Methods and Results sections are generally objective and trustworthy. They present the facts of how the study was done and what was found.
• Background, Discussion, and Conclusion sections are potentially subject to "spin." While these sections provide context and interpretation, readers should approach them with skepticism and critically evaluate the authors' claims and interpretations.