The fascinating science behind making learning stick

Humans forget.

You probably see this frequently in your business’ training programs. Regardless of how much time, money or effort you spend training your employees, it always seems to go in one ear and out the other.

Is there anything you can do about it?

Answering this question is critical in medicine. After all, you want your family practitioner, surgeon or paramedic to recall their years of training without fail. And, despite their busy schedules, medical practitioners need to continuously upskill to keep up with the constant advances in medical knowledge and patient safety.

So, it’s unsurprising that some of the most rigorous research into long-term memory retention techniques come from this field.

Two are worth looking at in more detail:

  • Interactive spaced-education to teach the physical examination: a randomized controlled trial – B. Price Kerfoot, Elizabeth G. Armstrong, Patricia N. O’Sullivan
  • Spaced education through e-learning for ongoing professional development – Alexander W. Hirsch and Joshua Nagler

Kerfoot’s interactive spaced-education research

In his groundbreaking research, Kerfoot combined two learning techniques into one approach he called interactive spaced-education (ISE):

  1. The spacing effect – the finding that people remember more when new learning is broken down into bite-size pieces and repeated multiple times over a period of time
  2. The testing effect – the finding that testing an individual’s memory makes learning stronger and easier to retrieve.

He wanted to see if ISE would improve Harvard Medical School students’ knowledge of the physical exam – the basic diagnostic tool used in clinical practice.

How it worked

Thirty-six daily emails were sent to second-year medical students over six weeks – each containing a clinical scenario and a question. Students would answer the question and immediately learn whether their response was right. They would also see an explanation of the answer. The cycle was then repeated twice more in the same order.

The trial’s results

When Kerfoot analysed his results, they were impressive.

  • During the first cycle, students on average answered 57.9% of questions correctly
  • During the third cycle, students on average answered 74.4% of questions correctly – an increase of 16.5 percentage points

What’s more, the program was well-received:

  • 85% of participants would’ve recommended the ISE program to PD2 students the following year
  • 83% of participants wanted to participate in a similar ISE program the following year
  • Participants thought the ISE program was highly effective – rating it 4.3 on a five-point scale (1 = not effective, 5 = extremely effective).

Hirsch and Nagler’s spaced-education research

Hirsch and Nagler’s research was conducted at Boston Children’s Hospital Division of Emergency Medicine. As many doctors there found standard training methods difficult to fit in with their busy schedules, Hirsch and Nagler thought a more innovative approach was required.

So, building on Kerfoot’s research, they turned to spaced education, testing and gamification to solve the problem.

Gamification is when you apply gaming techniques such as leaderboards, points and badges to education. Done right, gamification increases learners’ engagement and knowledge retention.

How it worked

Hirsch and Nagler tasked experts to come up with multiple-choice questions in four subject areas. The experts also provided:

  • A detailed explanation of the correct answer
  • A clear explanation as to why alternative responses were wrong
  • Links to related policies and guidelines

This content was uploaded onto an online microlearning platform.

Participants answered one question a week. Once they answered, they’d immediately see:

  • Whether they were right or wrong
  • The explanation of the correct answer
  • The percentage of colleagues who’d selected each answer option

If a question was answered correctly twice, it was retired. But get the answer wrong, and the question returned (after a spaced interval).

An anonymised leaderboard ranked participants perform in comparison to their colleagues.

The trial’s results

Participation was high, with 100% of staff and students at the Division of Emergency Medicine engaging with the program at some point. What’s more, 92% of participants completed all the questions.


  • 5% of participants gave the correct answer on the first attempt
  • 3% of participants gave the correct answer on repeat testing

For the three most challenging questions:

  • 41% of participants gave the correct answer on the first attempt
  • 93% of participants gave the correct answer on repeat testing

Participants loved the approach and thought it was of high value. They could learn on the go, easily fitting in training with their busy schedules. Answering a question a week was also a simple task, requiring little time or effort to complete.

Practice makes perfect: how to help your staff learn

You want to develop your staff – and that means training. But one-time events and elearning modules that go on and on don’t have the desired effect. Your staff quickly forget everything they’ve learned and you’re straight back at square one.

If you want better results, work with the brain rather than against it. Use spaced learning techniques.

Here’s how:

  • Break your training up into short sessions – so you don’t overload your learners with too much information at once
  • Space out your training sessions over time – to beat the forgetting curve
  • Revisit material again and again – so the learning sticks
  • Boost learning and give real-time feedback – with frequent quizzes
  • Engage your learners – using points, leaderboards and badges

Don’t know where to start? Get the training results your business needs by emailing