Scientific writing is a distinct skill that differs from the essay writing you learned in English composition. It demands clarity, precision, evidence-based argumentation, and a specific structural format. For pre-health students, scientific writing appears in lab reports, research papers, literature reviews, grant proposals, personal statements, and the clinical documentation you will produce throughout your career. The MCAT® CARS section tests your ability to analyze complex written arguments, a skill that improves as your own writing improves. This guide covers the principles of effective scientific writing, the standard formats you will encounter, and strategies for developing your skills.
Principles of Scientific Writing
Clarity Over Elegance: Scientific writing prioritizes clarity above all else. Every sentence should convey one idea, stated as simply and directly as the subject matter allows. Avoid flowery language, unnecessary jargon, and complex sentence structures that obscure meaning. If a sentence requires rereading to understand, it needs revision. Use active voice (“we measured cortisol levels”) rather than passive voice (“cortisol levels were measured”) whenever possible, because active constructions are shorter, clearer, and identify who performed the action.
Precision: Use specific, quantitative language instead of vague descriptions. “The treatment significantly reduced blood pressure” is imprecise. “The treatment reduced systolic blood pressure by an average of 12 mmHg (95% CI: 8 to 16 mmHg, p < 0.001) compared to placebo” is precise. Specificity builds credibility and allows readers to evaluate your claims. When you reference data, include the actual numbers, units, and statistical context.
Evidence-Based Argumentation: Every claim in scientific writing must be supported by evidence, either from your own data or from cited sources. Unsupported assertions undermine credibility. When you make a claim, immediately follow it with the evidence that supports it. When the evidence is from another source, cite it. When the evidence is your own data, reference the specific result. This evidence-claim linking is the structural backbone of scientific writing.
Objectivity: Present findings and arguments based on evidence rather than personal opinion or emotional appeal. Acknowledge limitations honestly. Discuss alternative explanations for your results. Distinguish between what the data shows and what you interpret it to mean. The discussion section of a paper is where interpretation occurs, and even there, speculation should be clearly labeled as such and supported by reasoning.
Common Scientific Writing Formats
Lab Reports: Follow the standard scientific format: Title, Abstract, Introduction (background and hypothesis), Methods (what you did and how), Results (what you found, including figures and tables), Discussion (what the results mean, limitations, future directions), and References. Lab reports in pre-health courses train you to communicate experimental findings in the format used by professional scientists. Write your Methods section in enough detail that another student could replicate your experiment. Write your Results section to present data objectively, saving interpretation for the Discussion.
Literature Reviews: Synthesize existing research on a topic rather than presenting new data. A strong literature review identifies the major findings, evaluates the quality of evidence, identifies gaps in current knowledge, and proposes directions for future research. Organize by theme or chronology, not by source. A literature review that simply summarizes one paper after another (a “book report” style) is weak. A review that identifies patterns, contradictions, and open questions across multiple studies demonstrates critical thinking.
Research Abstracts and Posters: Abstracts (150 to 300 words) summarize your research in a structured format: background, methods, results, and conclusions. Posters present the same information visually for conference presentation. Both formats require extreme concision: every word must contribute to communicating your key findings. Practice distilling complex research into brief, clear summaries, because this skill transfers directly to clinical documentation, where you will need to communicate patient information concisely and accurately.
Developing Your Scientific Writing Skills
Read Published Papers: The best way to learn scientific writing is to read it. Pay attention to how experienced authors structure their arguments, present data, and handle limitations. When you read a well-written paper, note the techniques that make it effective. When you read a poorly written paper (and you will encounter many), identify what makes it confusing and how it could be improved. See our reading scientific literature guide for systematic approaches to reading papers.
Write Regularly: Writing improves with practice, not with knowledge of rules alone. Write lab reports carefully, even when the course does not emphasize writing quality. Start a research blog or a study journal where you summarize what you are learning in your own words. Volunteer for research projects that involve manuscript preparation. Every piece of writing you produce is an opportunity to practice clarity, precision, and evidence-based argumentation.
Seek Feedback: Share your writing with professors, research mentors, writing center tutors, and study partners. Feedback from others reveals blind spots in your writing that you cannot identify yourself. Your campus writing center can help with both general writing quality and scientific writing conventions. Many research mentors will review and edit your drafts, which is one of the most valuable learning experiences in scientific writing.
Revise Ruthlessly: Good writing is rewriting. Your first draft captures your ideas. Your second draft organizes them. Your third draft clarifies them. Your fourth draft eliminates unnecessary words. Professional scientific writers revise extensively, and you should too. After completing a draft, set it aside for at least 24 hours before revising. Fresh eyes catch problems that tired eyes miss.
For related skills, see our reading scientific literature guide, research experience page, personal statement guide, and active learning guide.
Writing Application Essays vs. Writing Lab Reports: Pre-health students need two distinct writing skillsets. Scientific writing (lab reports, research papers) prioritizes objectivity, precision, and evidence. Application writing (personal statements, secondary essays, activity descriptions) prioritizes narrative, reflection, and personality. The mistake many students make is writing personal statements like lab reports (detached, clinical, devoid of emotion) or writing lab reports like personal statements (subjective, narrative-driven, lacking data). Recognizing which mode of writing each context requires and being able to switch between them is a mark of a mature writer. See our personal statement guide and personal statement prompts for application writing guidance.
Citation and Reference Management: Proper citation is fundamental to scientific integrity. Learn a standard citation format (APA, AMA, or whatever your program requires) and use it consistently. Reference management software like Zotero (free and open-source), Mendeley (free), or EndNote can help you organize sources, generate formatted reference lists, and insert in-text citations automatically. Starting to use reference management software during your undergraduate years saves enormous time as your research and writing responsibilities increase in professional school and beyond. Accurate citation also protects you from plagiarism, which can have career-ending consequences in academic and professional settings.
Getting Published: For students interested in research, publishing your work in a peer-reviewed journal is a significant accomplishment that strengthens applications to competitive programs. Start by contributing to a faculty member’s research project and ask about opportunities to co-author a paper or present a poster at a conference. Many undergraduate research journals exist specifically to publish student work. Your research mentor can guide you through the submission and peer review process. Even if your first submission is not accepted, the revision process teaches you to respond to critical feedback constructively, a skill you will use throughout your career.
References
Day, R.A., and Gastel, B. “How to Write and Publish a Scientific Paper.” 9th Edition, Cambridge University Press, 2022.
Strunk, W., and White, E.B. “The Elements of Style.” 4th Edition, Longman, 1999.
National Library of Medicine. “PubMed.” NIH, 2025. https://pubmed.ncbi.nlm.nih.gov/. Accessed March 2026.