The extent to which a specific health care treatment, service, procedure, program or other intervention does what it is intended to do when used in a community dwelling population is termed its :-: (A) Efficacy, (B) Effectiveness, (C) Effect modification, (D) Efficiency
Answer is B. Effectiveness looks at how the intervention works in real-life settings. Efficacy, tests the same in controlled or laboratory settings. Effect modification is all about stratification & occurs when an exposure has a different effect among different subgroups. Effect modification is associated with the outcome but not exposure.