IQ—or more accurately the theory of general intelligence—is highly controversial inside the field of psychology. In fact a part from developmental psychologists

IQ—or more accurately the theory of general intelligence—is highly controversial inside the field of psychology. In fact a part from developmental psychologists—which might use IQ tests to determine if a child requires special needs—I bet by far most psychologists go their entire career without ever touching an IQ test or citing a paper because of IQ results. It is true that the debate about general intelligence is huge. So you see a lot of papers written about it. But this is a subfield inside psychology (in fact a subfield of psychometrics which is a subfield of psychology; the whole field of psychometrics invoking skepticism among many scientist). I’m gonna do you a favor and list sub-fields of psychology that work regardless of the theory of general intelligence and therefor work just fine without IQ: * Cognitive psychology (and computational psychology) * Neuropsychology * Social psychology (and psychological sociology) * Pathological Psychology and Psychiatry * Developmental psychology (although they might use IQ tests; but for different reason as psychometricians do) * Psychological first aid (not a science but a method; similar to paramedics but for trauma victims) And here are some generic theories inside psychology which have nothing to do with—and might reject—the theory of general intelligence. * Behaviorism * Neurological determinism * Evolutionary psychology * Psychoanalysis Even inside psychometrics (which is the believe that any psychological effect that exists is measurable; and that operational definition is a legitimate way to describe psychological effect) I bet there are people that reject the theory of general intelligence on the grounds that IQ is not measuring general intelligence, but something else.