Are Method Effects Permanent or Ephemeral in Nature? The Case of the Revised Life Orientation Test

摘要

This research investigated the nature of the method effect associated with positively worded items of the Life Orientation Test-Revised. In a first cross-sectional study (N = 1 1,028) the best fitting model posits 2 factors, representing general optimism and a specific factor associated with positive items. In a second longitudinal study (N = 203). a unified latent curve latent state-trait model was used to assess the developmental trajectory of the specific factor from 16 to 20 years. This factor contains a prevalence of trait versus state variance, and presents a relationship pattern with external criteria (e.g., depression) that differ from the one involving general optimism.