- May 4, 2022
- 5 min read

How best to revise – according to science

Credit: Stories (Freepik)

Tips & tricks / by Conor D’Andrade

Are you struggling to cram as much information into your brain as possible for your upcoming exams? Here are some tips to make the process easier and more efficient (and dare we say, far more enjoyable!)

Revision is hard. It’s time consuming, often boring, and can even feel like it’s making no difference. But the evidence is clear: people that revise perform better when tested. So why is it that no matter how many times you re-read that paragraph, you just can’t remember it for the big test? Well, quite simply, it's because not all methods of revision are created equal.

To get the best – or indeed any – results out of investing time in revision, a quality approach is needed, and unfortunately, reading the same text-book chapter over and over doesn’t cut it. Thankfully though, psychologists have provided us with a scientific understanding of the best way to revise!

Make your revision an active process

The biggest mistake people make when revising, is that they don’t actually revise – they study, or rather they re-study. This isn’t to suggest that studying shouldn’t be a part of revision; revision is a process, with study being its first step. However, when revision consists of only re-studying content, our ability to retain that information is limited.

So, what's the difference between the two? Studying refers to when we are initially learning about something, for example when reading through a textbook. As we do this, we passively remember the information. The issue is – and the reason we need to revise – we often don’t remember this information very well. This is why people often resort to simply re-studying the information again in the hopes to refresh that memory and remember it better.

Unfortunately, because of the passive nature of studying and re-studying, when trying to learn the volume of content needed for an exam or several exams, this relatively ineffective method of committing information to memory is not very useful. This is why revision must always be an active process!

But what does this “active” part of the process actually look like? Well, rather than just re-studying the section in the textbook you want to remember for the test, produce a poster summarising the information in that section. By engaging with the information, it is committed to memory much more effectively.

Test to remember!

We have known for a long time that one of the best ways to remember something, is to test yourself on it. This was in fact first demonstrated as early as 1937 in an experiment where participants were asked to study several geometric line drawings. They were then asked to reproduce the drawings once or several times immediately after study, 1 day, 1 week, 1 month, and 2 months later. The difference in effect, between those who only had to recall the image once and those who had to recall it multiple times, on the amount of the pattern they could recall was striking!

The effect of testing on information recalls, demonstrated as far back as 1937! Source: Hanawalt, 1937.

As you can see, participants that were tested (by reproducing the drawings) several times, remembered the drawings significantly better and more consistently across the two-month period, than those who were tested only once. In fact, the repeated recall group consistently recalled the drawings over the two months, almost as well as on the day of learning. On the other hand, the single recall test group steadily declined in its ability to recall the drawings. This difference is known as “the testing effect!”

Testing is a great way of making revision into an active process – after studying the passage you want to remember, test yourself on it, and test yourself on it repeatedly!

Make testing part of your revision process!

Not yet convinced of the importance of testing rather than studying when revising? Maybe 1937 is a bit too old a study to be taken seriously anymore? Then here's another study for you.

In 2008, scientists carried out a complex experiment to measure the differences between studying and testing on memory. Participants initially had to study 40 word pairs, before they were then split across several different conditions and groups: either they were asked to study the word pairs again, or they were tested on them by recalling the word pairs.

Across the two-week study, the more word pairs a participant had been tested on, the more word pairs they could recall on the final test. To be specific, participants that were in the retrieval conditions (being tested on word pairs rather than studying them again) recalled 80% of the word pairs a week later, compared with just 33–-36% recalled by participants in the study conditions.

As you can see, testing really is much more effective for remembering information than just studying it –- according to this study, almost 50% better!

Maximising the benefits of the testing effect

While it is enough to incorporate testing into your revision process and see dramatic improvements on test scores, there are some simple ways to make it even more effective for committing information to memory.

1. Leave enough time between tests for them to actually test you

Firstly, it is important to consider the difficulty of the testing you are doing. When testing is easy, the testing effect is small, and because of this, it is important to leave a period of time between studying and testing to ensure a reasonable level of difficulty.

For the same reason, it is also better to use spaced intervals of testing rather than massed intervals. By allowing for longer periods of time between testing, we keep the difficulty enough to maximise the testing effect.

2. Check your answers!

Secondly, you must consider the impact of feedback on the testing effect. Research has found that testing with feedback (checking your answers) is significantly better for remembering information than just testing. While it seems obvious to check your answers, it turns out the time between testing and receiving feedback is also important!

In an extremely interesting experiment, participants learnt by either study, a test with no feedback, a test with immediate feedback, or a test with delayed feedback. Again, the results were striking!

Clearly, we can see evidence again that testing is an effective means of remembering, as the ‘no test’ group performed by far the worst on the final test.

More importantly though, we can see that the two groups that received feedback on their test performed significantly better than the group that did not. Evidently, feedback improved retention of information. However, beyond this we can still see a difference between the two feedback groups, with those that received delayed feedback performing the best.

So, what should this mean for your revision?

Well, after testing yourself on what you have studied, rather than immediately checking what you got right and what you got wrong, wait ten minutes and then check, as it really does make a difference!