The current study examined the degree to which applicants applying for medical internships distort their responses to personality tests and assessed whether this response distortion led to reduced predictive validity. The applicant sample (n = 530) completed the NEO Personality Inventory whilst applying for one of 60 positions as first-year post-graduate medical interns. Predictive validity was assessed using university grades, averaged over the entire medical degree. Applicant responses for the Big Five (i.e., neuroticism, extraversion, openness, conscientiousness, and agreeableness) and 30 facets of personality were compared to a range of normative samples where personality was measured in standard research settings including medical students, role model physicians, current interns, and standard young-adult test norms. Applicants had substantially higher scores on conscientiousness, openness, agreeableness, and extraversion and lower scores on neuroticism with an average absolute standardized difference of 1.03, when averaged over the normative samples. While current interns, medical students, and especially role model physicians do show a more socially desirable personality profile than standard test norms, applicants provided responses that were substantially more socially desirable. Of the Big Five, conscientiousness was the strongest predictor of academic performance in both applicants (r = 0.11) and medical students (r = 0.21). Findings suggest that applicants engage in substantial response distortion, and that the predictive validity of personality is modest and may be reduced in an applicant setting.