17 rules of plain English writing

Knowing and applying these 17 core rules of plain English writing will help you develop your health communication skills, write industry-leading content and create better health outcomes.

Medical writing in plain English is an in-demand skill, regardless of whether you work on articles, health blogs, patient education materials or medical copywriter projects.

This 17 rules of plain English writing post contains my top rules and tips for writing clear, readable health content. The post is perfect for you if you want to write health & medical content for the public, including your own patients.

Don’t forget to bookmark the post so you can refer to it whenever you need a refresher!

Rule 1. Choose a useful health topic

Address these essential considerations when choosing a health topic.

• Define the purpose of your content in one sentence (what is the point?)
• Define your readers in as much detail as possible
• Articulate how the health topic is useful and helpful for your readers
• Put yourself in your readers’ shoes and think about what they want to know about the topic

Rule 2. Conduct background research for your writing

Take the time to ensure you understand your topic properly.

• Research your topic until you can explain it simply
• Consult a variety (eg three to five) of high-quality sources and experts to enhance your understanding
• Collect the full studies of any background research (not just the abstracts or press releases)

Rule 3. Plan

Planning makes the writing process easier.

• Define your topic
• Consider the key questions your readers would have about that topic (your readers’ goals)
• Break up your topic into sections based on your readers’ key questions

Rule 4. Create a consistent look and feel

Ensure your content has a consistent, clear overall look and feel.

• Use consistent white space – ensure there is at least 1.5 line spacing between headings and paragraphs
• Use a clear font size and type – use a clear, consistent font type and use at least 12 point for web writing
• Implement a hierarchical font structure – eg size 12 for body copy, size 14 for subheadings (H2), size 16 for the main heading (H1)
• Put headings in bold – all headings and subheadings should be in bold to stand out
• Aim for a beautiful-looking page in general – step back and look at the entire page as a whole to make sure it looks neat and easy to read

Rule 5. Write plain English sentences

Follow these tips to ensure your sentences are clear and readable.

• Use short sentences (no more than two lines) – ideally, keep sentences shorter than two lines or around 25 words
• Vary your sentence length – change up your punctuation and tone to create a smooth flow and prevent monotony
• Use short paragraphs (no more than four to five lines) – break up long paragraphs; ensure paragraphs don’t exceed five lines
• Use links – insert internal and external links, with important key words hyperlinked

Rule 6. Implement an effective structure

Follow these tips to implement a clear structure.

• Clearly state the main point at the beginning – your readers need to immediately know what they’re reading and why they should care
• Include bullet lists instead of sentence lists – bullet points and numbered lists help readers to digest your content; make sure any lists have consistent punctuation and formatting
• Use subheadings – subheadings help readers to scan your content; include subheadings that contain your key points
• Ensure your subheadings are specific – make sure subheadings are clear and specific (use a slightly larger font size)
  • Useful subheading: What are the symptoms of postnatal depression?
  • Vague subheading: Symptoms

Rule 7. Avoid complex grammatical structures

Follow these tips to reduce the complexity of your writing.

• Use plain, everyday English – tools like Grammarly and Hemingway can help you understand the difference between plain English and complex English
• Avoid rare and unusual words – use the most common English equivalent
• Reduce words with four or more syllables – extra syllables are difficult to read.

Rule 8. Avoid jargon and define complex medical terms

• Define complex medical terms using plain English, or remove jargon entirely
• Spell out acronyms the first time, place the acronym in brackets and then refer to it throughout the rest of the content
• Example: Parkinson’s disease (PD) is a disorder of the nervous system. PD results from damage to the nerve cells that produce dopamine …

Examples of simplified explanations of medical terms

• Aortic regurgitation – when your heart’s aortic valve doesn’t close properly
• Carotid dopplers – an ultrasound of the blood vessels in your neck
• Pacemaker – a small device which helps maintain a healthy heartbeat using electrical impulses

Examples of plain English medical terms:

• Kidney disease instead of renal disease
• Heart disease instead of cardiovascular disease

Rule 9. Write in the active voice

The active voice is clearer and more direct, while the passive voice can confuse readers or leave out essential details. Passive voice is not incorrect – it is, however, less clear and often uses more words than the active version.

• Rewrite passive sentences to active sentences where appropriate

Active voice: The subject is doing the action

Passive voice: The action is being done to the subject OR the action is done without mention of a subject

Tip: Use a readability tool like Grammarly or Hemingway to identify passive voice.

Rule 10. Use plain English terminology

Avoid talking about patients as sufferers and victims of illness.

• Use empathetic, person-centred language – eg a person with diabetes/cancer/heart diseases NOT cancer patient/heart disease sufferer/diabetic
• Avoid stigma and stereotyping – be aware of the language you choose
• Be aware of the nuances of communicating about mental health and disability – see these guidelines for in-depth strategies for disability communication
• Where possible, use people, not patients

Rule 11. Personalise communication

Write like you’re having a conversation with someone who is in the same room as you.

• Use “you” and “we” (not “the client” or “the company”)
• Use person-centred language (people, not patients; people with a disease, not diseased people)
• Use Grammarly or Hemingway to help you check the readability score of your work

Rule 12. Use consistent terms

If you use key terms like doctor and GP interchangeably, your readers may think you’re referring to two different people.

• Ensure your main terms are consistent
• Be aware of differences in medical terminology and spelling between countries and in different cultures

Examples of key terms to keep consistent

Rule 13. Use specific plain English language

Specific language avoids doubt and is more direct.

• Avoid vague terms like in two weeks and use specific dates instead

Rule 14. Create engagement

As health writers, we don’t just write about health. We need to engage our audiences. Here’s how you can make sure your content has the best chance of captivating your readers.

• Use “you” and “we” instead of the third person, eg ”the patient”
• Include a story or anecdote
• Incorporate humour where appropriate
• Ask questions to encourage your readers to reflect
• Use metaphors, for example: the heart is like a pump, the heart’s valves are like doors that open and close

Rule 15. Maintain relevance

If your content isn’t relevant, your readers won’t continue reading.

• Put yourself in your readers’ shoes and think about what interests them
• Address your readers’ pain points, questions and concerns
• Use an appropriate tone and voice for the topic you’re writing about

Rule 16. Implement quality control and compliance

Being a high-quality health writer involves being a responsible health writer.

• Double-check your facts and health claims
• Share your work with people who can confirm you have adequately represented the research
• Link your health claims to the original sources
• Ensure your messaging is socially responsible
• Ensure your messaging is consistent with local guidelines
• Consult your local marketing and advertising guidelines
• Consult relevant subject matter guidelines and ensure your communication is consistent with recommendations, eg disability/inclusiveness guidelines
• Ensure your writing is culturally appropriate

Rule 17. Make a strong overall impression

Step back and look at your content.

• Ensure your key take-home messages are memorable
• Give your readers a way to continue their journey after they’ve finished reading
• Scan your content to ensure the key points are clear in the subheadings
• Ask others to review your content and tell you if any aspects are unclear

Summary of key plain English writing principles

The core best practices in brief, for quick edits and reviews.

1. Choose a useful health topic
2. Conduct background research
3. Plan
4. Create a consistent look and feel
5. Write readable sentences
6. Implement an effective structure
7. Avoid complex grammatical structures
8. Avoid jargon and define complex medical terms
9. Write in the active voice
10. Use appropriate language
11. Personalise communication
12. Use consist terminology
13. Use specific language
14. Create engagement
15. Maintain relevance
16. Implement quality control
17. Make a strong overall impression

The final word

Remember that high-quality health content changes lives and makes a difference.