The pretesting effect: why testing yourself before you learn works

What is the pretesting effect?

Most students think of a test as the thing that happens after learning. The pretesting effect turns that around: you take a short test first, on material you have not studied yet, and then you study it. You will get most of the questions wrong. That is expected, and it is part of why it works.

It is a close relative of retrieval practice, the well-known finding that testing yourself after studying beats reading again. Pretesting asks a different question: does an attempt to retrieve help even when there is nothing to retrieve yet? The answer from the research is mostly yes.

What does the research show?

The study that named the effect is Richland, Kornell and Kao (2009). Across five experiments, students read an essay about vision. Some answered questions about concepts in the essay before reading it; others simply got extra time to read. The pretested students did better on the final test in every experiment, and the authors counted only the questions they had failed on the pretest. So the benefit was not coming from things students already knew. The researchers even highlighted the tested concepts in bold or italics for the extra-reading group, to rule out the idea that pretests just tell you where to look.

Kornell, Hays and Bjork (2009) made the point sharper. They designed questions that people would almost always get wrong, such as made-up trivia, and still found that a failed attempt followed by the answer led to better memory than simply studying the answer for the same time. Their conclusion was that taking challenging tests, instead of avoiding errors, may be a key to effective learning.

The effect also works with video. Carpenter and Toftness (2017) had students watch a short video on the history of Easter Island, split into segments. Students who answered two questions before each segment remembered more on the final test, both on the questions they had seen and on new questions about the same video. In a review for the Psychonomic Society, Faria Sana (2023) describes classroom studies in which pretested material was remembered better on later quizzes and on midterms given weeks afterwards.

Why does guessing wrong help?

Researchers are still debating the exact mechanism, but three ideas come up again and again:

• It primes the right knowledge. Trying to answer pulls up related things you already know, so the correct answer has something to attach to when you meet it.
• It sharpens attention. Once you have guessed, you want to know if you were right. You read or watch with a question in your head instead of drifting.
• It shows you the gap. A wrong answer is a clear signal that you don't know something yet, which beats the vague feeling of familiarity you get from skimming.

The important part is that the correct answer arrives soon after the guess. A wrong guess left uncorrected is just a wrong guess.

How to pretest yourself, step by step

1. Before the lecture or chapter, get five to ten questions on it. Use the learning objectives, the end-of-chapter questions, last year's past paper questions on that topic, or questions generated from the slides your lecturer posted in advance.
2. Answer them honestly, without looking anything up. Write a guess for each one. "I don't know" is allowed, but a reasoned guess is better.
3. Study the material looking for the answers. Read the chapter or watch the lecture as normal. When you hit an answer, note it.
4. Check every pretest question. Make sure you now know the correct answer and why your guess was wrong.
5. Test yourself again a day or two later. This is ordinary retrieval practice, and it is where the long-term gains build up. Our guide to active recall techniques covers ways to do this.

Ten minutes of pretesting before a lecture is enough. You are not trying to learn the topic from the questions, only to prepare your mind for it.

When pretesting helps less

• When the answer comes much later. The benefit seems to depend on getting the correct answer reasonably soon after the attempt. Pretest right before you study, not a week before.
• With long, real lectures. A follow-up by Toftness and colleagues (2018) found smaller effects with full-length lecture videos than with short clips. Pretesting still helps you focus, but don't expect it to replace review.
• With younger children. Most of the research is with older students and adults. If you are a university or sixth-form student, you are the group it was tested on.
• If it makes you anxious. A pretest is not graded. Getting most answers wrong is normal and is part of the process.

An easy way to set up a pretest is to upload the slides or chapter before you study it. Ace turns a PDF, PowerPoint or Word file into practice questions written only from that material, lets you choose which chapters to play, and shows the sentence from your file that backs each answer, so you can attempt the questions first and check against the source straight after. The how it works page shows the steps.

Frequently asked questions

Sources

1. Richland, L. E., Kornell, N., & Kao, L. S. (2009). The pretesting effect: Do unsuccessful retrieval attempts enhance learning? Journal of Experimental Psychology: Applied, 15(3), 243–257.
2. Kornell, N., Hays, M. J., & Bjork, R. A. (2009). Unsuccessful retrieval attempts enhance subsequent learning. Journal of Experimental Psychology: Learning, Memory, and Cognition, 35(4), 989–998.
3. Carpenter, S. K., & Toftness, A. R. (2017). The effect of prequestions on learning from video presentations. Journal of Applied Research in Memory and Cognition, 6(1), 104–109.
4. Toftness, A. R., Carpenter, S. K., Lauber, S., & Mickes, L. (2018). The limited effects of prequestions on learning from authentic lecture videos. Journal of Applied Research in Memory and Cognition, 7(3), 370–378.
5. Sana, F. (2023). Test first, learn later: The power of pretesting to enhance learning. Psychonomic Society Featured Content.