A clinical health psychologist working at a company wants to know if workers' health would improve if they were given extra days 'off. In this company, all workers undergo a standard physical exam twice a year and after each exam an overall health rating (higher scores mean better health) is automatically provided to the company. To conduct the study, the psychologist selected five workers at random who would then receive an additional 2 days off every month over the period between health exams. The psychologist then compared the health scores on the two exams.

Health Rating, Before and After Period of Extra Days Off