The F scale measured personality through questionnaires, not explicit ideology like the other scales.

Evidence

It is natural to anticipate that the survey part of the study which used questionnaire items would yield the data on ideology and that the clinical part of the study would yield the data on personality. In fact the coincidence is not quite that sharp. The Anti-Semitism (A-S) Scale, the Ethnocentrism (E) Scale, and the Political and Economic Conservatism (PEC) Scale are all concerned with explicit ideology. However, the F Scale is concerned with personality. It represents an attempt to assess by questionnaire the personality trends that are also assessed by interview and by projective methods. — John T. Jost and Jim Sidanius, Political Psychology, 439

Categorization

• DEFINE: Clarifies that the F (Fascism) Scale was a personality instrument while A-S, E, and PEC measured explicit ideology — a distinction often lost in popular summaries of the study.
• XREF: connects to: The study’s character types were built from political doctrines, not psychology. — Rolf Wiggershaus, The Frankfurt School: Its History,…, 705; The F-scale measured how deeply ethnocentric attitudes were rooted in personality structure. — Rolf Wiggershaus, The Frankfurt School: Its History,…, 1769