ABSTRACT
Experimental science has been a part of psychology since William Wundt developed a research laboratory at the University of Leipzig in 1879. Wundt’s areas of interest included mental disorders and abnormal behavior – topics highly relevant to school psychologists. He was focused on consciousness and the elements constituting the human mind. Research is conducted to determine truths about a population based on observations from a sample. Establishing cause and effect relationships is a key goal of research. A causal relationship exists whenever changes in one variable cause changes in another variable. Causality is established whenever substantial evidence indicates changes in one variable depend on changes in another variable. Much assessment research in school psychology involves the development and evaluation of tools used to measure unseen psychoeducational, socio-emotional, and behavioral constructs. Assessment research in school psychology primarily follows correlational designs.
