Reaction time (RT) is commonly prolonged after a sport-related concussion. Besides being a marker for injury (e.g. one of the signs and symptoms of concussion ), a rapid reaction time is necessary for protective maneuvers that can reduce the frequency and severity of additional head impacts.
Because prolonged reaction time (RT) is one of the signs of sport-related concussion, a reliable and valid measure of RT is important to a clinician's initial diagnosis and management of concussions, including return to play decisionmaking. Studies show that
The Sideline-Dropstick test is a novel clinical test of reaction time using a device similar to one used in high school physics experiments and was initially developed by a group from the University of Michigan. 8,9,15
Studies show that it:
It should be noted that validation of the Sideline-Dropstick test in high school athletes is ongoing, but has not yet been done in middle school and younger athletic populations.14
To administer the Sideline Dropstick you will need to build a dropstick and use a random number generator (there are several random number generator applications available for free download on smartphones)
Here's how to make a dropstick:
The sideline-dropstick test may be administered on the sideline, though in our experience, we will commonly take the potentially concussed athlete to the training room to perform testing in a more controlled, less distracting environment than the sideline. We will compare their average performance on 8 drops with their baseline performance. We consider this measure of RT, along with the patient's performance on SCAT3  and BESS  testing when determining whether the patient may have sustained a concussion or not. Impairment of RT (a performance worse than baseline) should be considered a potentially significant marker of having sustained a concussion.
Jim MacDonald is a physician specializing in pediatric sports medicine at Nationwide Children's Hospital in Columbus, Ohio and Clinical Assistant Professor of Pediatrics and Family Medicine at the Ohio State University's School of Medicine and Nationwide. An Associate Editor of the Clinical Journal of Sport Medicine, MacDonald is a Fellow of the American College of Sports Medicine, and is a member of MomsTEAM Institute's Board of Advisors. He earned both his Bachelor's and Medical degrees from Harvard University, and his Masters in Public Health from The Ohio State University. He did his pediatric sports medicine training at Boston Children's Hospital and was previously Team Physician at the University of California, Santa Cruz before coming to Columbus.
As a clinical researcher Dr. MacDonald has received grant funding from the American Medical Society for Sports Medicine (AMSSM) and Nationwide Children's Hospital (NCH). He has experience leading multidisciplinary teams in a variety of research projects investigating the diagnosis and management of pediatric sport-related concussions and in the use of patient-reported outcome measures (PROMs) in the evaluation of pediatric musculoskeletal injuries. His publications and interests also include work on Exercise-Deficit Dysfunction (EDD) in children, a precursor to childhood obesity. Jim is the married father of ten-year old sports-active twins, a boy and a girl.
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