In this study, data for each observed opportunity for handwashing was recorded as correctly performed or not (yes or no). What level of measurement is this variable?

Read the following article to see how several researchers assessed the RR of nosocomial infections before and after a handwashing intervention. These concepts will make more and more sense to you as you see them used in actual clinical research. Chhapola, V., & Brar, R. (2015). Impact of an educational intervention on hand hygiene compliance and infection rate in a developing country neonatal intensive care unit. International Journal of Nursing Practice, 21(5), 486–492. doi:10.1111/ijn.12283