Study techniques ranked: the best study techniques according to the evidence

The best study techniques, ranked by evidence

Most advice on study techniques is opinion. This page uses two of the most important research reviews instead. In 2013, Dunlosky et al., 2013 reviewed ten popular techniques and rated each as high, moderate or low utility. In 2021, Donoghue & Hattie, 2021 ran a meta-analysis of the same ten techniques: 242 studies, 1,619 effects and 169,179 participants.

The short version: the two best study techniques are spacing your study out over time and testing yourself. The techniques most students actually use, rereading and highlighting, are at the bottom. The ranked table on this page shows all ten with the numbers from the meta-analysis.

How to read the numbers

The table reports each technique's effect size, d. It describes how much better learners did with the technique than without it, in standard deviations. A common rule of thumb: 0.2 is small, 0.5 moderate, 0.8 large. The overall mean across all ten techniques was 0.56.

Three cautions before you use the ranking:

• These are not head-to-head contests. Each study compared a technique with its own control condition. A d of 0.47 for rereading does not mean rereading is almost as good as practice testing. When the two are compared directly, testing wins on delayed tests (Roediger & Karpicke, 2006).
• Results vary a lot. The authors report high heterogeneity (I² of 85%), meaning effects differ widely between studies. Context matters.
• Most outcomes were surface learning. Across all techniques, effects were much larger for surface outcomes (d = 0.60) than for deep processing (d = 0.26). The ranking is most reliable for learning facts and concepts.

One small note: Donoghue and Hattie's table labels two techniques differently from the original review (imagery and interleaving). We use the ratings from Dunlosky et al.'s own review in our table.

High utility: the two techniques to build your study around

Among university students, the subgroup closest to most certification candidates, Donoghue and Hattie report d = 0.89 for distributed practice (115 effects) and d = 0.80 for practice testing (278 effects): large effects by the usual rule of thumb.

1. Distributed practice (spacing)

Spread study of the same material over several sessions rather than cramming. Meta-analytic d = 0.85, the highest of the ten. The best gap grows with the time until your exam (Cepeda et al., 2006), and the effect holds in real classrooms, d = 0.54 (Mawson et al., 2025). Full guide: spaced repetition.

2. Practice testing

Answer questions, use flashcards or recall from memory, rather than rereading. Meta-analytic d = 0.74. Retrieval practice often produces large gains in long-term retention compared with restudying (Roediger & Butler, 2011). Full guides: active recall and the testing effect.

Moderate utility: useful with the right material

3. Elaborative interrogation

Ask yourself "why is this true?" and answer it. d = 0.56. Works best when you already know something about the topic. Guide: elaborative interrogation.

4. Self-explanation

Explain to yourself how a step, rule or example works. d = 0.54 in Donoghue and Hattie; a separate meta-analysis of self-explanation prompts found g = .55 across many instructional conditions (Bisra et al., 2018). There are limits: it suits principle-based domains, and explaining your own choices can sometimes reduce learning (Rittle-Johnson & Loehr, 2017). The Feynman technique is a popular version.

5. Interleaved practice

Mix related topics within a session. d = 0.47 overall. It helps most for similar, easily confused categories (g = 0.42 overall in Brunmair & Richter, 2019) and failed to show an effect in two large classroom maths studies (Rowlandson et al., 2025). Guide: interleaving.

Low utility: the techniques most students rely on

Rereading, highlighting and summarising

In a survey of 177 college students, most said they repeatedly reread notes or textbooks and few tested themselves (Karpicke et al., 2009). Rereading creates confidence that outruns memory: in one study, students' judgements of learning rose with every reading and they were overconfident a day later (Seban et al., 2024). Highlighting and summarisation had the lowest meta-analytic effects (d = 0.44 each). Summarising can still be useful if you do it from memory, which turns it into retrieval.

Keyword mnemonic and imagery

Dunlosky et al. rated both low utility. Mnemonics have their place for lists and arbitrary facts. A related technique, the method of loci (memory palace), had a medium effect, g = 0.65, in a meta-analysis of 13 trials, though with a high risk of bias (Twomey & Kroneisen, 2021). In one study, six weeks of method-of-loci training produced memories that were still better four months later (Wagner et al., 2021). See how to memorize things fast.

Matching techniques to exam content

Certification exams mix several kinds of content, and the techniques above do not suit them equally. This is our mapping, based on where each technique's evidence is strongest:

• Isolated facts (port numbers, acronyms, service names, process names): flashcards with spaced repetition. Interleaving adds little here; in the interleaving meta-analysis, blocking was better for word lists.
• Concepts (why a control works, how a protocol behaves): elaborative interrogation and self-explanation first, then practice questions to check you can apply them.
• Calculations (subnetting, earned value, annual loss expectancy): study a worked example, explain each step to yourself, then solve fresh problems from memory on later days.
• Scenario questions (best next action, most appropriate service): practice testing with mixed, interleaved sets, and a written reason for every wrong option.
• Processes and architectures: draw them from memory, then compare with the source. This combines imagery with retrieval.

Whatever the content, spacing and testing sit underneath everything else. The other techniques decide what you do in a session; spacing and testing decide when and how you come back to it.

A technique that does not work: learning styles

The idea that you learn best when teaching matches your "style" (visual, auditory, kinaesthetic) is one of the most popular beliefs about studying. A major review found virtually no evidence for this matching idea and no adequate evidence base for using learning-style assessments (Pashler et al., 2008). A later review found effect sizes across rigorous studies were very low and non-significant, and called learning-style matching a neuromyth (Aslaksen & Lorås, 2018).

Choose techniques by what the material and the exam demand, not by your preferred style. Everyone benefits from spacing and testing.

Does learning about techniques actually help?

Yes, there is some evidence. In a course study, students who learned about evidence-based strategies used fewer low-utility and more high-utility strategies, and improved by about one third of a letter grade compared with a control semester (Brown-Kramer, 2021).

The hard part is sticking with techniques that feel worse. Spacing, testing and interleaving all feel effortful, and learners often read effort as a sign of poor learning (de Bruin et al., 2023). Knowing that this is expected is part of the solution; see desirable difficulties and metacognition.

How to use this for a certification exam

A weekly template that puts the ranking into practice, for about 8 to 10 hours of study per week:

1. Start: diagnostic. Take our free Security+ practice test or AWS practice test to find your weakest domains.
2. Every session (practice testing + spacing): open with 10 to 15 questions on material from 3 to 7 days ago.
3. New material (elaboration + self-explanation): read or watch one objective, then close it and explain why it works and when you would use it. Write 5 questions about it.
4. Twice a week (interleaving): a 20-question set mixing similar topics you tend to confuse.
5. Weekly (practice testing): a mixed, timed set of 30 to 40 questions across all domains.
6. Use sparingly: rereading only to look up what you got wrong; highlighting not at all; mnemonics only for lists such as port numbers or the order of phases.
7. Every two weeks: retake our free practice test and shift time toward the lowest-scoring domain.

For a full 8-week plan, see how to study for exams. For the complete overview, see how to study effectively.