Establishment of Normative Clinical Reaction Times in a Pediatric Population

Abstract

INTRODUCTION: The puck-drop (PD) test has been utilized to assess clinical reaction time (CRT) and has been proposed as a tool to aid in the management of sports related concussion. The simplicity of the test and low cost make it an attractive tool in the management of these injuries; however, no normative data has been established in children, making post-concussion testing in this population difficult to interpret. PURPOSE: The purpose of this study is to examine the use of the PD test in the pediatric and adolescent population: 1) to develop age specific normative values and 2) to examine the effect of sex and handedness on test performance. METHODS: Patients (ages 8-18) who presented to sports medicine clinics for evaluation and treatment of non-concussive injuries and whose presenting complaint would not confound completion of the PD test (LE injury, recovered injury, etc.) were recruited for baseline assessment. Testing was conducted in accordance to protocols previously described in the literature. Two practice trials were conducted. The distance of stick transversal was recorded to the nearest 0.5 cm, as well as the number of drops and failed attempts. The test was completed when 8 successful trials for each hand were recorded. Children with hands too small to circumvent the puck diameter were accommodated by starting at 10 cm above the puck base at the discretion of the test administrator. RESULTS: 463 subjects completed the study (n = 178 male, n = 285 female, average age 13.04 +/- 2.57 years). Regression analysis of baseline CRT indicated a strong effect of age on overall CRT for both right and left hands (R2 = 0.21, p < 0.001, Figure 1). The estimates (SE) of right hand CRT ranged between 255.51 (4.66) to 216.15 (4.97) ms, and those of left hand ranged from 257.41 (4.71) to 219.08 (5.02) ms across 8-18 years of age. There were no differences in performance on CRT based on handedness (p = 0.78) or sex. (p = 0.84). CONCLUSION: As a result of this study, normative values for the PD test were established for the pediatric population. Test performance varied with age. Test performance did not vary based on hand, preliminarily indicating hand dominance does not affect performance during this evaluation, Future studies should evaluate the effect of concussion on performance.