Ethos and credibility: The construct and its measurement after three decades

Three decades of research involving the definition and measurement of the source credibility construct are reviewed and a new study reported. It is concluded that factor analytic research reported over the past decade has strayed from the original credibility/ethos construct and has treated that construct as virtually isomorphic with the construct of person perception. It is argued that future factor analytic studies of source credibility would serve no useful purpose, that the historical definitions of the construct should be retained, and that satisfactory measures of that construct already exist.