Spaced Repetition for the MCAT^®, Done Properly

You already know what spaced repetition is. The Duolingo owl has been living rent free in your notifications for years. Same idea here, higher stakes, zero guilt-tripping birds.

The gap between doing it and doing it properly comes down to about three decisions. Let's make them.

Why the Gaps Do the Work

Spacing is one of the most replicated findings in memory research, no cap. The Dunlosky review we leaned on earlier gave distributed practice its top utility rating. The best single study on timing comes from Cepeda and colleagues, who tested 1,354 people across study gaps and test delays of up to a year. With total study time held constant, the best gap produced 64 percent better recall than doing both sessions back to back.

The timing detail underneath that result matters more than the headline. The ideal gap depended on how far away the test was. For a test one week out, the sweet spot was roughly 20 to 40 percent of that week. For a test a year out, it shrank to roughly 5 to 10 percent of the year. The ideal gap grows as your test gets further away, just more slowly than the calendar does.

Then there is medicine specifically. Deng, Gluckstein and Larsen surveyed 72 medical students and found that the number of unique Anki cards they had seen predicted their Step 1 score, even after controlling for MCAT^® score, grades, and test anxiety. A 2025 systematic review found the same direction across studies and was upfront that the evidence is mostly observational. Step 1 is basically the MCAT^®'s older cousin: fact-heavy, high-stakes, same caffeinated brains. It tracks.

How the Scheduler Thinks

PurpleCAT's flashcards run on SM-2, a classic scheduling algorithm first written for the SuperMemo software. Every time you rate a card, it picks that card's next date. First pass, tomorrow. Second pass, six days after that. From then on it multiplies the last gap by the card's ease, which starts at 2.5 and shifts with your ratings. Easy bumps the ease up. Good nudges it down a hair. A miss sends the card back to day one.

Now the part that catches almost everyone. The scheduler has no idea when your test is.

Take a card you first learn 60 days before the MCAT^®. Rate it Easy every time and it comes back on days 1, 7, and 23, then disappears until day 68. Your test was on day 60. That card spent the final five weeks in witness protection.

Cepeda's data says your gaps should stay proportional to the time you have left, and near test day that means short. So build in a victory lap. In the last two weeks, open flashcard study, pick your decks, switch off due-only, and run every card once whether it is scheduled or not.

Keep the Deck in Its Lane

The same Deng study put a price tag on a Step 1 point, and it is quietly the most useful number in this entire article.

About 1,700 unique flashcards bought one point. So did about 445 practice questions. Both work. Questions bought points roughly four times faster per item, which is why cards belong in the side-quest slot.

Three rules keep them there:

• Cap your new cards. Every card you add today comes back tomorrow, again next week, and again a few weeks later. Twenty new cards a day turns into a mountain by week three. If reviews start taking more than an hour, pause new cards until the pile shrinks.
• Show up daily. Skipped days stack up and wait for you. A short daily session beats a heroic Sunday every time. Protect the streak like the owl is watching.
• Rate honestly. Hitting Easy on a card you half-knew is delulu. The scheduler believes you, ships the card off for weeks, and it shows up on test day as a total stranger.

Save cards for the facts that have to be instant: amino acid codes, the equations the AAMC writes out, vocab, hormones, anything that should never cost you more than two seconds. Twenty minutes of cards, then go do questions. Understood the assignment.

Sources

• Cepeda et al., Spacing Effects in Learning: A Temporal Ridgeline of Optimal Retention (2008)
• Deng, Gluckstein and Larsen, Student-directed retrieval practice is a predictor of medical licensing examination performance (2015)
• Anki Use and Academic Performance in Medical Education: A Systematic Review (2025)
• Dunlosky et al., Improving Students' Learning With Effective Learning Techniques (2013)