What to do now that the references for inclusion in the systematic review have been selected?

You are now nearly ready to write up the systematic review. You have reviewed the full text versions of any references that looked promising for inclusion, culling out those that were inappropriate (remembering to record reasons and numbers). You have read the references that have been selected and are sitting down ready to write about the subject.

For an initial systematic review, it is acceptable to tabulate the relevant data and discuss it, without performing any further analysis. This is a purely descriptive approach and although you will provide your writing groups opinions on the results, you may not want to do any further analysis. However, to get the most out of a systematic review you will probably want to go further. This could involve one of two approaches, either a meta-analysis or a narrative synthesis.

What is a meta-analysis?

If the references detail studies that are similarly designed, with similar duration, populations and study drug/intervention use, then a meta-analysis is possible. Meta-analysis are typically used in medicine and are a statistical approach to estimating the treatment effect. By combining a number of different studies, larger populations can be explored and this can provide insight into rare complications or adverse events, or provide a better overview of clinical efficacy. A good introduction to what a meta-analysis is can be found here.

What is a narrative synthesis?

If the references all include very small study populations, or the study designs are different, for example the study lengths vary widely, then a narrative synthesis may be more appropriate. This approach involves the identification of themes and trends in the research, highlighting aspects that appear to influence outcomes or are important for the intervention. A good introduction to what a narrative synthesis is can be found here.

Do you have any tips of writing a good systematic review?

First off, write the manuscript with the PRISMA checklist next to you, to ensure that all the information that it requires is included. Also, even though it may appear that the conduct of a systematic review is rigid and does not allow any creativity it is important that the final manuscript is not overly dry, otherwise no-one will read it and it is wasted effort. Ensure that the story of why the systematic review was conducted is included and that each step or question builds logically from the previous one. You do not want to make any sudden jumps, as although you may find them intuitive, your readers quite likely will not. They have not been immersed in the review and discussions around it. To avoid this, you should get a colleague who has not been involved in any discussions about the systematic review at any point to review a near-final draft. They are likely to identify any gaps in the narrative and you should listen to them and if you disagree you discuss your reasons with that person. Also, don’t forget to thank them in the acknowledgements.

Don’t just write, make sure you read as well

One of my favourite quotes about writing comes from Austin Kleon who says:

“In every undergraduate creative writing workshop I was part of, there was that one kid who said, ‘I like to write, but I don’t really like to read,’ and it was evident right away that you could pretty much write that kid off completely.”

This is because if we write without reading first we cannot build upon the work of others and we cannot learn from people who have published before. This should be self-evident but often when we are researching and experimenting, we will do a search to help us overcome an issue and will skim through to locate what is hopefully the answer. You might not fully read the introduction or conclusions, not really caring for the context or analysis for someone else.  We do not have time to read each article in depth and have time for research, for writing, for lecturing, for mentoring and for a life outside the research institute. Yet here I am suggesting that you should be reading more in our already packed lives.

If we do not want to learn and develop then this is not something that you should commit to, however, if you do there is always time to be found, even if it is just 15 minutes a day, possibly whilst sitting on the toilet. To improve you should read great writing; this does not have to be a ‘classic’ like Crime and Punishment, but should be something relevant. I would suggest that as writing up research is akin to non-fiction writing, it can be beneficial to read scientific non-fiction books, which can also provide ideas for research or help develop new ways of thinking. This can be science magazines, books or blogs.

Some suggestions for things to read

However, we shouldn’t limit ourselves, great writing is great writing and we can always learn something from it, hopefully, how to tell the best stories possible.

Austin Kleon – http://tumblr.austinkleon.com/post/33792291289

Why is everything a story?

When we think about scientific and technical writing we generally do not think of the outcome as a story. Indeed, saying that it is a story might be considered by some people as an insult, as they consider stories to be made up and not based completely on fact. However, to me every time we communicate we are trying to tell a story. We are trying to convey ideas in a logical and step-wise manner, leading people through our considerations and thoughts and showing how we reached our conclusions.

To demonstrate my thinking I shall break down a manuscript into its constituent parts and highlight how this links to story telling.


This is you ‘hook’ into your research or review. Why are you asking these questions? What led you to make the decision to undertake this project? It generally ends with you hypothesis and ideally readers will be asking the same question as you at this point.

Methods and Results

These are the story of what you did to test your hypothesis and the data/results you obtained. Once again there should be a logical flow as to why you did the experiment based upon your hypothesis and how further experiments and analyses build upon this initial experiment.


This is the denouement of your story where you pull together everything you have learned from your research, together with what was known before and discuss what you have learned and how it affects thinking on the topic being researched. It may also include a cliffhanger where next steps are discussed.


Whilst I wrote this I was listening to Decade of Viper