Reliability of Position and Mobility of the First Ray in Experienced and Inexperienced Examiners. Crystal Shirk, BS, ATC Context: The first ray is an essential part of the gait cycle and manual measurements of the first ray are a common part of a biomechanical examination. Problems with first ray position or mobility may lead to stress fractures, hallux valgus, metatarsalgia, acquired flatfoot, tendonitis, and plantar ulcerations. Although this measurement is quite common, little research has been completed on the reliability of this measurement. Objective: The purpose of this study is to determine intra and interrater reliability for Root's method for measuring first ray position and mobility for experienced and inexperienced examiners. Design: This study is a single-blind prospective reliability study. Setting: The study took place at HealthWorks Rehab & Fitness in Morgantown, WV. Patients and Other Participants: A total of 36 subjects volunteered for this study. A total of four examiners were utilized. Two were inexperienced (I1 & I2), having less than two years of experience working as a certified athletic trainer, and two were experienced (E1 & E2), having more than six years of experience working as a certified athletic trainer or physical therapist. A total of five recorders volunteered to record data for each examiner. Interventions: All subjects signed up for two time periods on two different days. Subjects were assigned a different letter as a code with only the principal investigator aware of the identity of the subject. Prior to data collection, examiners were shown Root's technique for measuring first ray position and mobility and practiced for twenty minutes. Examiners were detained in a room while subjects were positioned by the principal investigator in a supine position on treatment tables. A curtain was pulled around the table to blind the examiner from the subjects. After all subjects were positioned, the four examiners entered the room. The right foot's first ray was examined following Root's technique for position and mobility and the results were reported to the examiner's recorder. The examiner then moved to the right of the subject to evaluate the right foot of the next subject. This process was repeated until all right feet were evaluated. The examiners began again with the first subject they initially assessed and following the same procedures, examined all left feet for first ray position and mobility. Position was assessed as plantarflexed, dorsiflexed, or normal. Mobility was assessed as hypermobile, hypomobile, or normal. After both right and left feet were assessed and results were recorded, examiners retreated back to the holding room. All subjects, examiners, and recorders returned a week later, repeating the same procedures. Main Outcome Measures: The expectations of the study were to determine that experienced examiners would have moderate to high intrarater and interrater reliability for position and mobility while inexperienced examiners would have low to moderate intrarater a...