Extracorporeal shock wave therapy (ESWT) has been used in various musculoskeletal disorders, including lateral epicondylitis. However, in 2005, a meta-analysis of randomized controlled trials showed that ESWT provides minimal or no benefit in terms of pain and function in patients with lateral epicondylitis. Since the review, several randomized controlled trials including different types of ESWT such as radial type for lateral epicondylitis have been published. Investigations of the effect modifiers such as symptom and follow-up duration on the effects of ESWT on lateral epicondylitis have not been performed.