Retrieval practice (the testing effect) Metacognition: knowing what you know
The classic study: testing yourself beats rereading after a week
In short: Students who read a passage and then tried to recall it from memory remembered more two days and one week later than students who simply read it again. Rereading won only on a test five minutes later, and it made students more confident, which is part of why rereading feels better than it works.
| Paper | Test-Enhanced Learning: Taking Memory Tests Improves Long-Term Retention |
| Authors | Henry L. Roediger III, Jeffrey D. Karpicke |
| Published | 1 March 2006 · Psychological Science 17(3), 249–255 |
| Study type | Lab experiments (landmark classic) · Peer-reviewed |
| What we read | Abstract only. Summary based on the published abstract only. |
| Summarized |
What they did
In two experiments, students studied short prose passages. Then they either took one or three free-recall tests with no feedback, or restudied the passage the same number of times. A final test came 5 minutes, 2 days or 1 week later.
Who took part
University students in two lab experiments.
What they found
- After 5 minutes, repeated studying beat repeated testing.
- After 2 days and 1 week, prior testing produced substantially better retention than restudying.
- Repeated studying made students more confident that they would remember, even though they remembered less later.
Effect size: Exact percentages are not in the abstract; see the paper.
Limitations
- Lab studies with prose passages and university students.
- Free recall with no feedback; classroom results are covered by later meta-analyses such as Yang et al. (2021).
- We read only the abstract.
What this means for learners and parents
- Close the book and write or say what you remember. It feels harder than rereading and works better a week later.
- Don't judge a study method by how confident it makes you feel the same day.
Put it into practice (free tools)
Citation
Henry L. Roediger III, Jeffrey D. Karpicke (2006). Test-Enhanced Learning: Taking Memory Tests Improves Long-Term Retention. Psychological Science 17(3), 249–255. https://doi.org/10.1111/j.1467-9280.2006.01693.x
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