An easy way to update your literature review quickly

If it’s been a while since you last looked at the literature (or a specific area of the literature), here is a very quick way to find recent relevant papers.

Pick a few (5-10) important papers you already know are relevant to your work or the area you want to look at. It’s highly likely that anyone doing similar research will cite some of the papers you already know about. So if you look up those papers on the journal’s website and check the “cited by” information, you can find some recent gems.

This is especially useful in the time between submission and your thesis defence.

See also

How to grow your bibliography from just one paper

How to build your bibliography from just one paper

Most journal articles aren’t that important. Reading them (or not reading them) has no real impact on your research.

But, occasionally, you will find a paper that just fits. It’s relevant. It’s high quality. And most importantly, it influences the way you think about or go about your own research.

There will be relatively few of these (perhaps 5 or 10 in total during your whole PhD) but the impact they have is massive.

Once you’ve found one of these papers, (let’s call it paper A) you can use it as a seed to grow the rest of your bibliography. Here’s how…

First, look at the references in paper A. If the work is highly relevant to your own, the chances are they will cite other sources that are relevant to you. They have already read through the relevant literature and are telling you where to look.

Then, look up the authors of paper A; what else have they published? What do their departmental or LinkedIn profiles say they are working on now? This is not only to find other potentially relevant articles, but also to get to know who is working on similar topics (the field consists of people, and you need to know who they are).

Finally, look at who else has cited paper A. Most academic search engines and many journal pages include “cited by” information for each source. Anyone else doing similar work to you is likely to cite many of the same sources, so this is a good way to find results that you may not have found through a search engine.

This final step can also give you an indication of how paper A has influenced the field. It’s also a good step to repeat to find out if anything relevant has been published recently (after you submit your thesis but before your defence, for example)

If you repeat this process using the best papers you find, you can quickly find a good number of other high-quality, highly relevant sources. This doesn’t replace keyword searches, but it’s a very quick and very effective addition.

See also
Searching for literature: Why google scholar is a blunt instrument
How to read a journal article
Filtering the academic literature


How to read a journal article

We all know that reading the literature is essential, but it’s not enough to just sit and read a stack of articles. Reading journal articles is a skill and, like any other skill, how you approach it makes a big difference. So it’s not just a question of how to read a journal article, but how to learn how to do it.

When you’re an experienced academic, reading journal articles is relatively easy. This is because you already have knowledge of the field and enough experience to recognise the significance and quality of the work. In other words, you can see where an individual paper sits in the wider context.

But as a PhD student, initially at least, you don’t have that experience. So, while plenty of academics have written guides on how to read journal articles, you can’t necessarily follow the same process as them (yet).

General principle:

While you can learn a lot from experts, the processes they follow now aren’t always the best ways to train your own skills. This is because their processes rely on prior experience.

How to learn to read an academic journal article

Instead of focusing on how to read an individual article, let’s think about what you’re actually trying to achieve. Are you trying to build your knowledge of the field? Or trying to understand a specific technical point? Are you trying to find a gap in the literature? Depending on the answer, the papers you choose to read, and what parts of those papers you focus on, should be different.

Of these, the first aim should be to build some knowledge of the field. How do you do this without drowning in thousands of sources?

1. Identify the most influential sources

Journal articles can be divided into two main categories; there are groundbreaking, influential papers that change the way the field thinks or operates, then there are incremental papers that just add a little bit, but don’t have a huge impact.

If you understand the influential, groundbreaking work, this gives you a foundation for understanding the incremental work that followed. Fortunately, there are relatively few of these groundbreaking papers and they are easy to identify (because they are highly cited).

Try to find around 5 highly influential sources related to a specific topic. If you can understand;

  • what they discovered/ invented/ proposed
  • what problem this discovery/ invention/ proposal attempted to solve

Then you have a good start. However, there’s a problem…

If you look just at those original sources, they might be very hard to understand. Simply re-reading them won’t necessarily help, because academic articles usually assume a lot of pre-existing knowledge.

2. Focus on the concepts you identify, not the sources

If you’ve identified important developments in the field, but don’t really understand them, you now have a new aim; to find sources that explain those concepts.

Primary research articles may not be the best things to focus on, because they aren’t written to teach. Instead, look for textbooks, review articles, Wikipedia pages, YouTube videos, or people in your institution you can ask.

You can go back to the original source later. For now it’s enough to know where the idea came from, while looking elsewhere for an initial explanation.

3. How did these concepts influence the field?

A key part of understanding the literature is understanding trends in your field. So what effect did these influential papers have?

For example, did a particular theory spark a bitter debate in the field? Did a particular invention open up new possibilities for research? Or did a particular discovery reshape the fundamental understanding of some phenomenon?

This gives you an initial, broad context for understanding some of the finer detail contained within the literature. But equally importantly it gives a focus to your reading; a specific, achievable aim that isn’t too overwhelming.

4. How to read journal articles for context

You can strengthen this contextual knowledge by reading the introductions of recent papers. Every research article starts with a brief overview of the background and current state of the art, so reading just the introductions of a few recent journal articles is a great way to get a quick summary of what’s happening in the field.

You may find that a lot of them say more or less the same thing. In this case, you know what the field considers to be important. Or if you see they all say contradictory things, you know that there is no consensus in the field.

Again, the aim determines how you read the individual journal articles and what you focus on.

5. Get some practical experience

It isn’t enough to know how to read a journal article. You will find that it gets much easier to read and understand once you have some practical research experience. It’s by doing research yourself and making mistakes that you’re able to spot problems in the published literature and to really appreciate the best work that’s been done.

Reading helps with the practical work, but the practical work helps reading too.

How to read a journal article once you’ve got a bit of experience

Once you’ve built up some broader contextual knowledge, you can think about how to read a journal article in isolation.

Many people advise reading the abstract first, then the conclusion, then going back to the introduction. The exact order varies (and this one advises skipping the abstract altogether), but it’s basically a way of systematically assessing whether the article is worth reading in depth.

Again, though, I’d say that how you read should depend on what you want to achieve and what led you to the article in the first place. Context is everything. You might read differently depending on whether you’ve just done a search that gave you 5000 results and need to filter through them, or you’ve done a search that resulted in 5. In the former case, filtering by title initially is the only way to go. In the latter case, slow down and read everything.

If you found a paper because you’ve noticed a lot of relevant sources referring to it, it’s probably best to treat it like one of the ground-breaking papers, but also noting what the authors you have already read are saying about it.

So you have to adapt, but as a general approach to reading journal articles…

Read the introduction first

I would usually advise reading the introduction first. The introduction should set out what the paper aims to do, and if you skip this then nothing else will make sense.

The first thing to look for is what problem they are working on. If it isn’t clear, or if the problem isn’t interesting to you, move on to the next article.

What you do next depends on the immediate relevance to your project

Key point:

Different literature will be useful to you at different times, depending on what you are trying to achieve. You may re-visit some sources several times throughout your PhD, and what isn’t relevant or useful now may become useful later.

If the work seems highly relevant to what you are doing, or helps you to solve a current problem in your research, either slow down and read carefully, or if you don’t have time, put it to one side but make sure you have a way of remembering where to find it later.

You don’t have to summarize everything

Some say that you should summarize everything you read, but I don’t think this is the most important thing to do. It’s possible to fill fifty notebooks with summaries, but that isn’t the same as having knowledge.

What you need is a picture of the literature (the key discoveries, most relevant articles and the trends in the field) which you carry in your head at all times. Then you where to look to find relevant sources to fill in some details when you need to.

What I did in my own PhD was build up collections of literature around certain topics. I put printed copies into ring-binders by sub topic. Any notes were taken in the margins of the paper, so they stayed in context with the whole text.

I knew which were crucial to my work and I knew which were most influential. I also knew the kinds of problems that were being worked on in the field, and what techniques were being used, and I knew where to look to find details when relevant.

See also:
How to write a compelling literature review
How to filter the academic literature


Day 14: How to tell good research from bad

60/60: 60 short videos for PhD students in 60 days

A few days ago, I talked about filtering the literature. There are 3 main criteria for this; quality of research, relevance to your work and influence on the field. But how can you judge the quality of the work? How can you tell good work from bad? You have to get experience doing your own research. Without this, the only experience you have is what other people have said. Start getting practical experience of research and analysis as early as possible.

Day 12: How to filter the academic literature

60/60: 60 short videos for PhD students in 60 days

Looking for day 14? I sent the wrong link in a recent email… You can find day 14 on how to tell good research from bad here

In the last few videos, I’ve talked about starting with the most influential, groundbreaking papers before going into an iterative process of reading the less influential material.
To do this, you need a way of filtering the literature so you can decide where to put your attention. I do this with 4 categories; A, B, C & D.
The A-rated papers are the absolute best and most relevant sources. These are the ones that significantly affect your work (i.e., if you took them away, your work would be completely different). There will be relatively few of these, but you will read them many, many times.
The B-rated papers are high quality and relevant, but maybe not quite essential. They influence the way you think, but your work doesn’t absolutely rely upon them. There will be a lot more of these.
The Cs are not clearly relevant, but maybe interesting? They’re OK, and perhaps very important to someone else, but not to you. You can keep these and look at them again later if you need to.
The D rated papers are either not at all relevant or just low quality. There could be thousands of these. Don’t spend any time on them.
Remember, you can always re-categorise the papers later. It’s an iterative process!

How Long Should my PhD Literature Review be?

“How long should my literature review be?”

“How many references should my literature review include?”

“How much should I write about each source?”

These are very common questions because there are no clear or consistent guidelines on exactly how much you need to put into your literature review.

But the fact that there are no clear guidelines tells you something about the nature of literature reviews. It tells you that these are the wrong questions to ask and that if you want to write a good review, the length might not be the most important thing.

Dilution vs distillation

Sometimes, adding more content (to any chapter of your thesis) can make it weaker. By adding references just to bulk out the chapter, whether or not you have anything interesting to say about them, you can end up diluting the good stuff.

But if you stick to the things you know about and deliberately exclude sub-standard or irrelevant literature, the review will usually be much stronger.

Remember that your examiner has to spend their valuable time reading your work. They will only wish it was longer if it’s well-written and interesting.

Some better questions

So instead of asking how long a literature review should be, or how many references it should contain, it’s better to ask the following;

  • How do I select the best and most relevant literature?
  • How do I structure the literature into a compelling narrative?
  • How can I balance the need for detail with the need for breadth?

These questions aren’t easy to answer, but they focus your mind on the important problems.

See also:
How to write a compelling literature review


By Daniel SchwenOwn work, CC BY-SA 4.0, Link

Not everything you say needs a reference

Not everything you say in your thesis needs to be supported by a reference. It’s OK to present your own thoughts and observations, and you don’t always have to refer to someone else who’s already said it.

If you want to describe a technique or a theory, try describing it in your own words based on your own understanding and experience.

So instead of saying, “according to Smith, this theory is useful because…”, have the courage to state your own reasons.

You should of course cite sources where appropriate, but you should also include thoughts of your own. The examiners want to know what you think about your subject, not just what you’ve read about it.

What to do if there are no papers in your research area

I’m trying to write my literature review but there are hardly any published papers related to my work. What should I do?

If you think that a literature review needs to contain as large number of references, then this is a problem. But it’s not about the number of references, it’s about reflecting the state of the field as it is.

If there aren’t many papers to write about, this in itself is a worthwhile observation about the research in your field. Assuming you have good reasons why your research problem is important, a lack of pre-existing literature can help to justify your own work.

Also, if not much has been done already then it is far easier to make a significant contribution because the most basic questions haven’t yet been answered.

So it’s not necessarily a huge problem if there aren’t many papers to work with, provided you have good reasons why other academics should be interested in your work.

Go into detail on what is there

One advantage of having only a small number of sources is that you can be a bit more comprehensive, going into more detail about each paper. This just isn’t possible when there are thousands of articles (when you have to be much more selective).

Because you have fewer articles to choose from, you may end up citing lower-quality sources. If this is the case then it is OK to point out limitations in the existing research and use these as justification for further work.

Check the “cited by” information

If you have a few relevant papers, check to see who else has cited them. Maybe you wont find anything useful, but maybe you will find newer relevant articles that you might not have found through a keyword search.

You can also look up the authors of the papers you have to see what else they have published.

Broaden the search

Can you relate your work to a broader problem? Does it contribute in some small way to something larger? If you have a small number of articles in your niche, how do they frame their research in their introductions?

If there really are no papers to work with…

It is unusual for a research project to be completely unrelated to anything existing. Most research takes place on the edge of existing knowledge, not in an isolated void.

But if, somehow, you come up with an idea that is totally new, you have to think about who is going to be interested in it. The value of your work will be judged by other academics, whether in the form of a thesis defence or peer-review, so you need to find some way to relate it to problems other academics are interested in.

See also

How to find a gap in the literature

How to write a compelling literature review

How to find a gap in the literature

People often talk about “finding a gap in the literature”, but it’s not always clear what exactly that means or entails.

Part of the problem, I think, is that it’s one of those clichéd metaphors so commonly used that it’s easy to repeat without thinking about whether it makes any sense or whether it’s useful.

I wouldn’t ever tell anyone to try to find a gap in the literature as a starting point, because;

  • it’s not enough to just do something nobody’s done before; it needs to be of potential interest to the field
  • research ideas are developed, not found
  • how do you find something that isn’t there?

Instead of searching for a gap in the literature…

Instead of searching for a gap in the literature, think of it as finding an edge to work on; taking existing research and developing it further; improving upon it, answering open questions or taking it in new directions.

How to find an edge to work on

Start by just reading; when you find an interesting paper, think of how you could build upon it. A lot of the ideas you think of won’t be practical, but that’s OK! It’s better to come up with a lot of ideas and then refine them than to search for “the one”.

Not every article you read will trigger great ideas; if it doesn’t make sense to you or you don’t find it interesting then it’s probably not a good basis for your own research.

When you do find a potential edge to work on, you then need to go though a process of testing and refinement to examine the viability of your idea.

Check out the blog posts below for more on this, and feel free to ask any questions below (but please don’t ask me to give you a thesis topic)

See Also:

How to choose a thesis topic

Research proposals: a good idea is not enough

How to write a PhD literature review

By InkleinOwn work, CC BY-SA 3.0, Link