How many letters does the top answer for “any branch of psychology concerned with psychological measurements” have?

The most common answer is psychometrics (13 letters).

Crossword clue: any branch of psychology concerned with psychological measurements

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

psychometrics 13 letters wn-def

any branch of psychology concerned with psychological measurements

psychometry 11 letters wn-def

any branch of psychology concerned with psychological measurements