The use of experts and their judgments in nursing research: an overview.

Experts and their judgments are widely used in the fields of research, education, health care, law, commerce and technology. Expert judgment is known for its subjectivity and its potential for bias, which brings into question the accuracy and authenticity of judgmental data. At the same time there is acknowledgment of the valued contribution of judgmental data towards valid inferences in research and education. Maximizing the use of experts and their judgments has therefore become an endeavour of educationists and researchers alike. Since this is not a research article its purpose is to guide and assist nurse researchers with important methodological and ethical decisions when using experts. Experts must be used in the context of appropriate research methods such as the Delphi and Nominal Group techniques. Sampling of experts and sample size is determined by the type and quality of data and the availability of population data; purposive and maximum variation sampling techniques are recommended as appropriate when sampling experts. Universal research ethics must be applied with particular consideration of aspects which may influence the truth value of consensus among experts and marginalization of minority or extreme viewpoints. Quantification of judgmental data is recommended and is important to minimize bias and to increase the authenticity of research findings. The content includes: design considerations when using experts, sampling issues, ethical rules to be considered when enlisting experts and their judgments, optimal data collection approaches and managing judgmental data.