Karen Quigley

Sponsor: Army Research Laboratory

Reconsidering context: Theory and Measurement

Self-reports of experience are most often quantified via anchored, Likert-type rating scales (e.g., using a scale from 0-5, where 0 is no fatigue and 5 is maximal fatigue). Raters change how they use such scales when their internal bodily state changes, making such scales poorly reliable and invalid under such conditions. The investigators have developed a new normalized self-report rating scale method in which people map specific prior autobiographical experiences to person-specific scale metrics. The researchers will compare metrics from the new scales to traditional Likert-type metrics. They also will use a well-known (and safe) immune challenge, a typhoid vaccine, to assess whether the new scale method provides more reliable and valid self-report outcomes across different bodily states. A new method is important for testing new drug or behavioral treatments when pre- and post-treatment ratings of experience (like fatigue) are used to determine whether a new treatment is effective.