Comparators, timescales and incremental analysis: what is a comparator?

In this section we will discover why comparators and timescales are important in economic evaluations, and what incremental analysis is.

An economic evalution should compare an intervention with a realistic comparison, or comparator. This comparator should represent the practice that is most likely to be replaced if we decide to implement the new intervention. So, we can already begin to set some ground rules for the appraisal of economic evaluations: the comparator needs to be clearly stated in the research publication.

Example: "We compared the effect of treating a cohort of people with secondary progressive multiple sclerosis with interferon beta for 30 months against existing best practice without interferon beta. " Source: Population based cost utility study of interferon beta-1b in secondary progressive multiple sclerosis, Forbes R B, Lees A, Waugh N, Swingler R J. BMJ 1999;319:1529-1533.