The design of observer agreement studies with binary assessments.

Author(s): Freedman LS,  Parmar MK,  Baker SG

Journal: Stat Med

Date: 1993 Jan 30

Major Program(s) or Research Group(s): BRG

PubMed ID: 8446811

PMC ID: not available

Abstract: We discuss the design of observer agreement studies with binary assessments, with particular emphasis on the need for adequate sample size and the use of replicate observations. First, we present a method and tables for determining the sample size required for ensuring a desired precision for the estimate of the probability of disagreement between two observers. Second, for studies including replicate observations, we present a statistical model that allows estimation of the magnitude of within- and between-observer variation. We then derive sample sizes guaranteeing a specified precision for these estimates, present tables of these sample sizes and give examples of their use.