RESPONSE to the Relationship of the Amount of Physical Therapy to Time Lost from Work and Costs in the Workers' Compenstion System.

W e appreciate the opportunity to respond to the concerns raised by Leung et al. We are delighted that our research has garnered interest and intellectual discussion among the research community. Several concerns were raised by Leung et al regarding the provider types associated with current procedural terminology codes as listed in Appendix A of the previously published article. Our manuscript does not focus on specific provider types and instead focuses on the outcomes related to billable, physical methods for the treatment of injury. Similar methodologies in assessing ‘‘physical therapy’’ on healthcare utilization and cost has been applied in previous studies. We agree that effective physical therapy services may differ between providers and our article was careful to avoid generalizing to specific practitioners and as such, does not assess variations in care by provider types. Another issue discussed in the comment related to the categorization of physical therapy visits among claimants without services (zero visits) and those with one to three visits. Significant differences were not observed for claim characteristics and