When we learn in classrooms, there is a built in sequence of events that helps us go from initially learning a topic to full mastery. Our mastery of each topic is reinforced multiple times: after learning about the topic, we do homework involving it, take a quiz the next day, then prepare for said topic to appear in the final exam.
After all of these check-ins, we should have effectively retained all the concepts we’ve learned.
What is spaced repetition?
Spaced repetition visual from Achievable
Spaced repetition works the same way—in fact, it is defined by Behzad Tabibian et al. (2019) as “a technique for efficient memorization which uses repeated review of content following a schedule determined by a spaced repetition algorithm to improve long-term retention.” In a spaced repetition system (SRS), you are continuously quizzed until you gain mastery of the topic over time.
But where it gets more interesting is having the ability to optimize when you study. Further research has proven that studying something right as you’re on the edge of forgetting it actually helps it stick in your memory more when you do recall that item.
Furthermore, a SRS prioritizes studying things you missed, and studying the things that you know less often, which helps you retain the information effectively while minimizing the amount of time and material you need to review. Minimizing repetitions on material you already have mastered is key to maximizing your allotted study time’s impact on your score.
These reasons, taken together, are why spaced repetition is more efficient than studying the same things constantly.
Advantages of spaced repetition
1. Quizzing while studying is proven to be superior to the study-only approach.
According to Karpicke and Roediger (2003), the “use of repeated testing methodology while learning led to a 45 percent improvement in test scores over a non-testing study-only approach.” At the foundation of spaced repetition’s effectiveness is the fact that studying with intermittent testing is superior to studying alone. The brain tends to hold onto information better when you use it. If you quiz yourself on what you’ve learned, you’re more likely to master the concept and you are given insight into what topics you’re strong or weak in.
2. Periodic quizzing is more effective than traditional study methods for memory recall.
As shown by Modigliani and Hedges (1987), “use of distributed practice methodology led to approximately 46% better recall than traditional study methods for the same material.” At the heart of this quote is the word periodic–that is to say, quizzing yourself throughout your studying process is more effective than only quizzing at the end or not at all. Spaced repetition-based studying programs have you reviewing old content consistently while learning the rest for this reason.
3. Using an algorithmically-optimized study schedule and sorting reduces study time needed to master the material.
When you study with a computerized spaced repetition system, it contains an algorithm that estimates the point that you’ll forget each item you’ve learned. This timing serves two purposes: first, as we said earlier, studying when you’re on the edge of forgetting is more effective and makes the item stick in your memory longer. And second, by establishing the memory strength for each item over time, the SRS system will sort what you need to study in order of what is most urgent. These two principles help an SRS optimize your study schedule to help you remember the most material in the most efficient amount of time possible. In our own experiences, students typically achieve better scores in roughly half the time as traditional methods.
How to use spaced repetition in your own learning
Using spaced repetition in your own learning might seem daunting at first, but it is doable on your own – even with flashcards – and some open source and free software programs have made it easier.
Free digital options
One digital option for this is Anki, which is free and open source, lets you build your own flashcards, and has the spaced repetition aspect built into the program. Quizlet also lets you build flashcard decks online for free, but does not bake in the spaced repetition method, so you will need to track it manually similar to the paper flashcards option below.
If you are using paper flashcards, you can repeat the mechanics of spaced repetition yourself with a bit of work. First, make your flashcards. Then, make five boxes. Place all of the flashcards in Box #1. Then, quiz yourself on the flashcards: anything you get right, move it to Box #2, anything wrong, you keep in the beginning box – Box #1.
You will repeat this process for every Box that you study with: if you’re studying flashcards in Box #3 and get it right, move it to Box #4. If you get it wrong, move it to the beginning – Box #1.
If you’re studying for a test less than a month away, you can use a rough rule of “study this Box every N days”, where N is the Box number. For example, in this setup, you study Box #1 every day, Box #2 every other day, Box #3 every three days, Box #4 every four days, and Box #5 every five days. You can adjust these timelines as you see fit, but we recommend a maximum gap of 14 days between study sessions for Box #5.
We hope this is helpful! Spaced repetition is a powerful tool when it comes to remembering information over a large body of material or period of time. We bet it will be a powerful tool for your studying needs.