As stated in an obituary, "She made major conceptual contributions to the understanding of the manner in which psychological development is influenced by environmental and experiential factors.

Anastasi's summary of such work was blistering: "The array of evidence in support of this [Aryan supremacy] is incomplete and one-sided at its best, and fantastic and mythical at its worst.

"[9][13] Between the methodological difficulties involved and the horrors perpetrated by the Nazis, differential psychology largely disappeared as a field of research.

Anastasi pointed out that the "testing boom" of the 1920s caused the term IQ to be adopted and misused by the general public.

According to Anastasi, the misappropriation of the term created connotations that intelligence is heritable, stable throughout one's lifespan, and resistant to change.

They evaluate for what is in high demand within a specific context; what an individual can achieve in the future depends not only on his or her present intellectual status as determined by the test, but also on subsequent experiences.

[15] Therefore, Anastasi advocated against psychometric tests definitively labelling a person, as they assess for specific types of knowledge and do not account for how intelligence can change over time.

Anastasi mostly applied existing methods to individual and group ability testing, as well as self-report inventories and measuring interests and attitudes.

The essay "Psychological Testing: Basic Concepts and Common Misconceptions,"[17] encapsulates Anastasi's methodological positions.

An example is the Stanford Diagnostic Test in reading and mathematics, which assesses specific subject mastery by combining both interpretations.

In contrast, the Stanford-Binet Intelligence Scales aptitude tests are based on broad knowledge of American culture beginning in the twentieth century.

[17] Anastasi's theoretical framework that ability or intelligence change with experience and that their cultural context dictates their parameters informed her methodological approach to psychometric testing.

She emphasized that tests serve specific functions in Western society, such as school/occupational placement or to assess for mental disabilities.

[19] In the latest edition of the book, Anastasi and her co-author Susana Urbina suggested that more accurate results can be obtained by combining information from several fairly homogeneous tests.