Conversation so far:
what is the multivariate research?
Rather than pursue a "univariate" research approach to psychology, studying the effect that a single variable (such as "dominance") might have on another variable (such as "decision-making").
what else can you tell me about it?
Cattell pioneered the use of multivariate experimental psychology (the analysis of several variables simultaneously).

Question: what was being used before the multivariate?
Self-contained rewrite: what was being used before Cattell pioneered the use of the multivariate?