In striving to develop expertise, are 10,000 hours of deliberate practice really required, and must it be guided by a teacher or coach? In episode 59, we’re joined by Brooke Macnamara from Case Western Reserve University. She’ll discuss her attempted replication of the study which led to the mantra popularized by Malcolm Gladwell that these criteria are necessary to master a task. Her article, “The role of deliberate practice in expert performance: revisiting Ericsson, Krampe & Tesch-Römer (1993)”, was published with Megha Maitra on August 21, 2019 in the journal Royal Society Open Science.


Does Practice Make Perfect? - Brooke Macnamara
Does Practice Make Perfect? - Brooke Macnamara
Does Practice Make Perfect? - Brooke Macnamara Does Practice Make Perfect? - Brooke Macnamara
@rwatkins says:
In part since Brooke’s study calls into question the research at the foundation of what has become a lucrative expertise-building industry over the past 30 years, it’s little surprise that some don’t appreciate her line of research. Since her initial meta-analysis through today, she’s encountered many vocal opponents to her findings and conclusions. So we closed out our conversation by asking her what it’s like to be embroiled in such debates with luminaries from her field.
@rwatkins says:
Though neither the original study nor Brooke’s replication measured it, feedback on performance is often associated with developing mastery and even expertise over a skill. Brooke talked with us about what current research suggests about its effect on practice.
@rwatkins says:
Analysis of variance, or ANOVA for short, is a statistical technique used in the original study to compare the number of music competitions engaged in by the best versus good violinists, excluding less accomplished violinists. Ericsson then ran a second ANOVA between the best and good violinists grouped together compared against the less accomplished violinists. But ANOVAs were probably not appropriate for the data Ericsson collected for this measure, as Brooke explains next.
@rwatkins says:
Brooke’s study is a direct replication of Ericsson’s original research, though it makes a few exceptions from his original methods. This led Ryan and I to wonder how Brooke and her co-authors decided what aspects of the study should be updated and which should remain the same.
@rwatkins says:
As in the original study, Brooke’s replication asked violinists to recollect their practice habits since beginning the violin, with some doing so as early as four years old. Since recalling events that transpired long ago can be fraught with bias, Doug and I were interested in hearing how Brooke increased confidence in the accuracy of participants’ responses to such questions.
@rwatkins says:
When a scientist engages in open science and chooses to pre-register their study, their data collection and analysis plans are specified in advance of gathering data … and typically commit those plans indelibly via public websites, such as Pre-registration aims to separate exploratory data analyses from confirmatory, hypothesis-testing ones, as Brooke describes after this short break.
@rwatkins says:
Brooke’s article points out that Ericsson’s original publication included bold claims, such as: “it is impossible for an individual with less accumulated practice at some age to catch up with the best individuals.” If that were the case, then only a single example of evidence contradicting ‘impossibility’ is necessary to falsify it. Brooke shared her thoughts on the issue of why such strongly worded conclusions may capture headlines, but not the nuances of science.
@rwatkins says:
Unambiguous statements of how researchers intend to define and measure their variables are necessary before setting about any research study. While there might be multiple defensible ways that these operational definitions can be crafted, part of Brooke’s concern was how the construct of “deliberate practice” was operationalized in Ericsson’s original study, as well as how she ought to define and measure it in her replication.
@rwatkins says:
Prior to seeking to replicate Ericsson’s study, Brooke examined the combined effects identified in previous studies carried out by other researchers into deliberate practice. The domains in those studies ranged from music to education, as well as a variety of professional and amateur sports. Doug and I were interested in hearing what she learned from her meta-analyses, as well as what eventually led her to seek to replicate Ericsson’s 1993 work.
@rwatkins says:
While the idea that experts spend at least 10,000 hours dedicated to deliberate practice was popularized by Malcom Gladwell in his book Outliers, few people know much about what the original research actually involved. Here, Brooke describes Ericsson’s original study.
@rwatkins says:
The importance of deliberate practice in developing expertise has been a long-held foundation of the psychological literature ever since a 1993 seminal study by K. Anders Ericsson and his colleagues. Especially since Ericsson was brought onto the faculty at Florida State University while Doug and I were graduate students there, we were curious what motivated Brooke to investigate if she could replicate their results.
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Hosts / Producers

Ryan Watkins & Doug Leigh

How to Cite

Watkins, R., Leigh, D., & Macnamara, B. (2019, October 1). Parsing Science – Does practice make perfect?. figshare.


What’s The Angle? by Shane Ivers


Macnamara: It could be at this point, since people now know about the 10,000 hour rule that they could assume that they’re practicing more and that’s why they’re good.

Watkins: This is Parsing Science, the unpublished stories behind the world’s most compelling science, as told by the researchers themselves. I’m Ryan Watkins

Leigh: and I’m Doug Leigh today in Episode 59 of Parsing Science were joined by Brooke Macnamara from Case Western Reserve University. She’ll discuss her attempt to replicate the 1993 study, behind the mantra popularized by Malcolm Gladwell, that 10,000 hours of deliberate practice on a skill are necessary to become an expert in it. Here’s Brooke Macnamara.

Macnamara: Hi I’m Brooke Macnamara. I am currently an Associate Professor at Case Western Reserve University. I’m a cognitive psychologist in the department of psychological sciences. I was born in rural Virginia in the Shenandoah Valley. I’ve actually had a career before this current one. So when I was 16, I decided that I wanted to be an American sign language English interpreter. So I went to college for that initially, so my bachelor’s degree is in American Sign Language English interpretation. So I ended up getting interested in aptitude for interpreting. I did a master’s degree at Union Institute and University, which was sort of a non-traditional program you find your own mentors. And I got the research bug and I just couldn’t let it go. And there was nowhere else for me to go in terms of getting more research experience and education except a traditional PhD program. So I went to Princeton University and studied it under Andy Conway, who examines individual differences in cognitive abilities. And initially the idea was to get this PhD and then go back to interpreting but again research just kind of held on to me and wouldn’t let me go. So I stayed in the academic route and now I study a bit more broadly skill acquisition and expertise across domains.

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