Development and Validation of the Short Grit Scale (Grit-S)
Duckworth, A. L., & Quinn, P. D. (2009). 'Development and Validation of the Short Grit Scale (Grit-S).' Journal of Personality Assessment, 91(2), 166-174. doi:10.1080/00223890802634290. Study 5 is a West Point class of 1,248 cadets. The most-quoted statistic about grit, verified verbatim: cadets a standard deviation above average on the Grit-S were '99% more likely to complete summer training', with the Whole Candidate Score controlled, and the composite itself did not predict retention. Credé and colleagues point out that the sentence confuses an odds ratio with a probability, since about 94 per cent of cadets complete the programme, so a doubling of the odds corresponds to roughly a 2.6 per cent increase in the likelihood of completing. Duckworth conceded the point to NPR Ed on 25 May 2016, accepting that the line should have been phrased differently, not disputing the effect size, characterising grit's independent effect as small to medium and saying she would prefer to think of grit as a member of the conscientiousness family. [THE NPR MATERIAL IS NOT PEER-REVIEWED. It is a press interview, verified by the vault on 2026-09-24 through a syndicated copy because npr.org returned an empty body, and the article labels it an interview. Her one piece of pushback was
Duckworth, A. L., & Quinn, P. D. (2009). 'Development and Validation of the Short Grit Scale (Grit-S).' Journal of Personality Assessment, 91(2), 166-174. doi:10.1080/00223890802634290. Study 5 is a West Point class of 1,248 cadets. The most-quoted statistic about grit, verified verbatim: cadets a standard deviation above average on the Grit-S were '99% more likely to complete summer training', with the Whole Candidate Score controlled, and the composite itself did not predict retention. Credé and colleagues point out that the sentence confuses an odds ratio with a probability, since about 94 per cent of cadets complete the programme, so a doubling of the odds corresponds to roughly a 2.6 per cent increase in the likelihood of completing. Duckworth conceded the point to NPR Ed on 25 May 2016, accepting that the line should have been phrased differently, not disputing the effect size, characterising grit's independent effect as small to medium and saying she would prefer to think of grit as a member of the conscientiousness family. [THE NPR MATERIAL IS NOT PEER-REVIEWED. It is a press interview, verified by the vault on 2026-09-24 through a syndicated copy because npr.org returned an empty body, and the article labels it an interview. Her one piece of pushback was
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Duckworth, A. L., & Quinn, P. D. (2009). Development and Validation of the Short Grit Scale (Grit-S). Journal of Personality Assessment, 91(2), 166-174.