How To Read A Paper: Author Trisha Greenhalgh on the success of her bestseller on the basics of evidence-based medicine

Dr Trisha Greenhalgh is Professor of Primary Care Health Sciences at the University of Oxford. She is an internationally recognised academic, a practising GP and the author of the bestselling How To Read A Paper: The Basics of Evidence-Based Medicine, published by Wiley and the BMJ, now in its fifth edition.

She leads a programme of research at the interface between social sciences and medicine, with strong emphasis on the organisation and delivery of health services. Her research seeks to celebrate and retain the traditional and humanistic aspects of medicine while also embracing the unparalleled opportunities of contemporary science and technology to improve health outcomes and relieve suffering.

Her past research has covered the evaluation and improvement of clinical services at the primary-secondary care interface, particularly the use of narrative methods to illuminate the illness experience in ‘hard to reach’ groups; the challenges of implementing evidence-based practice (including the study of knowledge translation and research impact); the adoption and use of new technologies (including electronic patient records and assisted living technologies) by both clinicians and patients; and the application of philosophy to clinical practice.

Statistics Views talks to Dr Greenhalgh about the book’s success and his own career in statistics.

1. Congratulations on the success of How to Read a Paper: The Basics of Evidence-Based Medicine, now in its fifth edition which was published last year. How did the book come about in the first place?

Ruth Holland who worked at the BMJ suggested I write a book to demystify EBM. Sadly Ruth was killed in a train crash just as I was finishing the first edition. The book is dedicated to her memory.


2. What were your primary objectives when originally writing the book?

I initially wrote it as a series of lecture notes to get students to the stage when they were confident to approach Dave Sackett’s ‘big red book’ on clinical epidemiology, which most people (including me) were terrified of.

3. Did you anticipate the success the book would have? Had you seen that there was a gap in the market for this book?

Not really. I wrote the book partly to get my own head round the topics. I’m not terribly numerate, so explaining in words what the numbers meant helped me to understand them myself. I guess a lot of people are (or view themselves as) innumerate so they found the text particularly accessible.

4. The fifth edition was released last year. For those who have not yet been introduced to the book who will read this, what can the reader expect in this version?

More on patients, more on complex interventions, more on implementation.

5. Who should read the book and why?

Anyone who finds it helpful. I’m pleased that it seems to have two main audiences – students and postgraduates working for exams, and front-line clinicians wanting to provide best care for their patients.

6. Why is the book still of particular interest now?

EBM has become a movement. In some ways it’s gone too far – it’s been appropriated by managerialists who seek to control and monitor clinical practice in a way that EBM’s original protagnosists never anticipated. But EBM isn’t, in and of itself, a ‘bad thing’.

7. When and how does statistics play a role in evidence-based medicine?

As I say in the book, EBM is nothing more or less than the name we give to the technique of using mathematical estimates of probability and risk, derived from rigorous research on population samples, to inform decisions about individual patients.

8. What was it that inspired you to pursue a career in health care?

Never wanted to do anything else.

9. You continue to teach as Professor of Primary Care Health Sciences at the University of Oxford. As a university professor, what do you think the future of teaching medicine will be?

Medicine is a practice. So it has to be learnt by apprenticeship and by observing (and making) decisions about tests and treatments on real patients. We’ll continue to have simulation and classroom based teaching but for me the essence of learning medicine is at the bedside and in the clinic.

10. What do you think will be the upcoming challenges in engaging students?

Encouraging them to keep in touch with their intuitive side when the system is imposing ever more rules and protocols on them.

11. What is your current research focussing on? What are your main objectives and what do you hope to achieve through the results?

I do a lot of research at the interface between social sciences and medicine. One of my main interests right now is the study of the subjective experience of illness and disability from a phenomenological perspective using ethnography and qualitative interviews. It’s about as far removed from EBM as medical research could be. But I think it’s increasingly important as medicine confronts the problem of multi-morbidity, which affects every patent differently. The only way to assess the patient in multi-morbidity is as an individual and from their own perspective.

12. You have also edited seven other publications for Wiley. Is there a particular book that you are most proud of?

To be honest the one I’ll be most proud of is the one I’m working on currently – on the challenges of implementing evidence-based practice.

14. Do you get research ideas from your work as a doctor and incorporate your ideas into your teaching? Where do you get inspiration for your research projects and books?

Yes and yes. I think I was born with research ideas. Some people are. If these don’t come naturally, don’t try to make a career out of research.

15. You have a very active Twitter feed. What do you like about Twitter and how important has social media been in giving a voice to raise awareness of issues that you are concerned about?

It’s self-organising and very efficient. I only follow people whose work I am interested in. So I don’t get distracted into pictures of kittens or pop stars. Two research collaborations and two PhD students have come from twitter.

16. How does statistics play a role in your every-day work?

The statistician can tell us if the findings are statistically significant, but they can’t assess clinical significance. Every statistician I’ve ever worked with has known that – and sought input from clinicians before, during and after the data collection/analysis phases. It’s usually naïve clinicians or naïve researchers who think the statistics alone will tell you what best to do for the patient or what to put in the guideline.

17. What do you see as the greatest challenges facing the professions of medicine and statistics in the coming years?

Information overload, leading to loss of overview.

18. Are there people or events that have been influential in your career?

[a] My family keep me grounded. [b] My tutor at Cambridge, Dr Gordon Wright, taught me to think. [c] The then Professor of Medicine at Oxford, [latterly, Sir] David Weatherall, once talked me out of dropping out of medical school when I failed an exam. [d] Hundreds of colleagues, students and patients have all contributed to an exciting and fulfilling career.