Context: Athletic trainers are encouraged to work collaboratively with other health care professionals to improve patient outcomes. Interprofessional education (IPE) experiences for practicing clinicians should be developed to improve interprofessional collaborative practice postcertification. An outcome measure, such as the modified Readiness for Interprofessional Learning Scale (mRIPLS), could be used to determine the clinician's attitudes toward IPE and to determine the effectiveness of the experience. Objective: To determine select psychometric properties of the mRIPLS in practicing athletic trainers. Design: Cross-sectional. Setting: Online survey. Patients or Other Participants: A survey was sent to 2000 randomly selected practicing athletic trainers. A total of 173 (8.7%) participated, and complete data were available for 145 (7.3%). Intervention(s): The survey consisted of a demographic section and the mRIPLS. The mRIPLS consists of 23 statements scored on a 5-point Likert scale divided into 3 subscales: teamwork and collaboration (TWC), patient-centeredness (PC), and sense of professional identity (PI). Main Outcome Measure(s): Cronbach a was used to examine the internal consistency. The presence of a ceiling effect (>50% respondents selected the highest score) was determined for each question by examining means and percentages. Results: The overall internal consistency of the mRIPLS was acceptable (a = 0.872) along with the TWC (a = 0.917) and PC (a = 0.862) subscales. The PI subscale (a = 0.632) was not acceptable. A ceiling effect was identified for 10 questions, and =70% of respondents selected "highly agree" or "agree" for 22 questions. Conclusions: While the mRIPLS demonstrated overall acceptable internal consistency, all 3 subscales did not. In addition, the presence of a ceiling effect makes the use of this instrument as an outcome measure trivial. Therefore, the current version of the mRIPLS may not be the best outcome to assess openness for IPE or to measure the effectiveness of IPE experiences in practicing athletic trainers.