1. American Occupational Therapy Association (AOTA) (2004) Policy 5.3.1: definition of OccupationalTherapy practice for state regulation. Am J Occup Ther 58:694–695
2. Arrow KJ (1963) Uncertainty and the welfare economics of medical care. Am Econ Rev 53(5):941–973
3. Bureau of Labor Statistics (2014) Occupational outlook handbook, 2014–15 ed.” http://www.bls.gov/ooh/healthcare/physical-therapists.htm (accessed June 9, 2016)
4. Centers for Medicare and Medicaid Services (2014) National health expenditures accounts. http://www.cms.gov/NationalHealthExpendData/downloads/dsm-09.pdf
5. Cunningham E (2019) Professional certifications and occupational licenses: evidence from the Current Population Survey. Monthly Labor Review. U.S. Bureau of Labor Statistics. https://doi.org/10.21916/mlr.2019.15