Maths in biology and medicine · Accessible · Dissertation

Is BMI a good measure?: a maths EPQ idea

A title to start from

Is body mass index a sound measure, mathematically speaking?

A starting point, not your title. Change the case, the data or the comparison until it is yours, then agree it with your supervisor. Check your title.

Why it works as an EPQ

BMI divides by height squared; scaling arguments and data let you judge that choice.

Scope and difficulty

Accessible. Accessible. Use published anonymised data, never classmates' measurements.

The maths

Builds on these A Level topics: Exponentials and logarithms · Sampling and data.

You would learn:

Scaling and allometry
Log–log regression
Alternative indices

Learning maths beyond the course is expected in a maths EPQ, but you must understand and explain everything you use.

One possible plan

Explain why mass might scale with height to some power.
Estimate the power from published data with a log–log graph.
Compare BMI with an alternative index.
Judge what BMI is and is not useful for.

Pitfalls

Collecting body data from classmates.
Health advice.

Where to start reading

Search for: BMI height exponent 2.5 alternative
NHS Health Survey for England data

Prefer books, lecture notes, journal articles and official data to a single website, and record every source as you read (how to reference).

Next steps

Check your title Plan your timeline

Your EPQ must be your own work. These pages coach: ideas, structure, checklists and planning. Submitting text, proofs, code or analysis written by someone else or by an AI tool as your own is malpractice. How to use help and AI honestly.

The Extended Project Qualification is offered by several awarding bodies, including AQA, Pearson Edexcel, OCR and WJEC/Eduqas. A Level Math Revision is independent and is not affiliated with or endorsed by any awarding body or university. Summaries of the rules are in our own words: your school and your board's specification have the final say. Every idea here is our own.