[11] After studying 300 mental patients and 100 control subjects, in 1921 Hermann Rorschach wrote his book Psychodiagnostik, which was to form the basis of the inkblot test.

[27][40] Systems for Rorschach scoring generally include a concept of "determinants": These are the factors that contribute to establishing the similarity between the inkblot and the subject's content response about it.

[52] The key components of the Exner system are the clusterization of Rorschach variables and a sequential search strategy to determine the order in which to analyze them,[53] framed in the context of standardized administration, objective, reliable coding and a representative normative database.

The results of the structural summary are interpreted using existing research data on personality characteristics that have been demonstrated to be associated with different kinds of responses.

[71][72] Form quality, popular content responses and locations are the only coded variables in the Exner systems that are based on frequency of occurrence, and thus immediately subject to cultural influences; therefore, cultural-dependent interpretation of test data may not necessarily need to extend beyond these components.

[74] Below are the ten inkblots printed in Rorschach Test – Psychodiagnostic Plates,[75] together with the most frequent responses for either the whole image or the most prominent details according to various authors.

[83] Another survey found that 124 out of 161 (77%) of clinical psychologists engaging in assessment services utilize the Rorschach,[84] and 80% of psychology graduate programs teach its use.

[88] A subsequent computerized interpretation of Rorschach test scores, that included summary and conclusions [89] was developed in the 1970s by psychologists Perline and Cabanski, and marketed internationally.

The arguments for or against computerized assessment of the Rorschach is likely to remain unresolved for some time, as there is no absolute correct interpretation against which the different markers (scores) denoting mental health can be compared.

[101] In the 1959 edition of Mental Measurement Yearbook, Lee Cronbach (former President of the Psychometric Society and American Psychological Association)[102] is quoted in a review: "The test has repeatedly failed as a prediction of practical criteria.

[104] A 2003 report by Wood and colleagues had more mixed views: "More than 50 years of research have confirmed Lee J. Cronbach's (1970) final verdict: that some Rorschach scores, though falling woefully short of the claims made by proponents, nevertheless possess 'validity greater than chance' (p. 636).

Supporters of the Rorschach inkblot test believe that the subject's response to an ambiguous and meaningless stimulus can provide insight into their thought processes, but it is not clear how this occurs.

"[106] In the 1960s, research by psychologists Loren and Jean Chapman, at the University of Wisconsin, published in the Journal of Abnormal Psychology, showed that at least some of the apparent validity of the Rorschach was due to an illusion.

[107][108] A related phenomenon called "invisible correlation" applies when people fail to see a strong association between two events because it does not match their expectations.

[107] In 1992, the psychologist Stuart Sutherland argued that these artificial experiments are easier than the real-world use of the Rorschach, and hence they probably underestimated the errors that testers were susceptible to.

The authors conclude that "Otherwise, the Comprehensive System doesn't appear to bear a consistent relationship to psychological disorders or symptoms, personality characteristics, potential for violence, or such health problems as cancer".

Similarly, the procedures for coding responses are fairly well specified but extremely time-consuming leaving them very subject to the author's style and the publisher to the quality of the instructions (such as was noted with one of Bohm's textbooks in the 1950s[118]) as well as clinic workers (which would include examiners) being encouraged to cut corners.

Jones v Apfel (1997) stated (quoting from Attorney's Textbook of Medicine) that Rorschach "results do not meet the requirements of standardization, reliability, or validity of clinical diagnostic tests, and interpretation thus is often controversial".

[citation needed] This controversy stems, in part, from the limitations of the Rorschach, with no additional data, in making official diagnoses from the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV).

[citation needed] The American Psychological Association (APA) has a code of ethics that supports "freedom of inquiry and expression" and helping "the public in developing informed judgments".

[141] In his 1998 book Ethics in Psychology, Gerald Koocher notes that some believe "reprinting copies of the Rorschach plates ... and listing common responses represents a serious unethical act" for psychologists and is indicative of "questionable professional judgment".

On September 9, 2008, Hogrefe attempted to claim copyright over the Rorschach ink blots during filings of a complaint with the World Intellectual Property Organization against the Brazilian psychologist Ney Limonge.

APA ethical standard 1.23(b) states that the psychologist has a responsibility to document processes in detail and of adequate quality to allow reasonable scrutiny by the court.

[148] Hogrefe & Huber Publishing, a German company that sells editions of the plates, called the publication "unbelievably reckless and even cynical of Wikipedia" and said it was investigating the possibility of legal action.

[148] For those opposed to exposure, publication of the inkblots is described as a "particularly painful development", given the tens of thousands of research papers which have, over many years, "tried to link a patient's responses to certain psychological conditions.

[151] Later that year, in August 2009, two psychologists filed a complaint against Heilman with the Saskatchewan medical licensing board, arguing that his uploading of the images constituted unprofessional behavior.

Benjamin Radford, editor of Skeptical Inquirer magazine, stated that the Rorschach "has remained in use more out of tradition than good evidence" and was hopeful that publication of the test might finally hasten its demise.

[156] The mask of the fictional antihero of the same name in the graphic novel limited series Watchmen and its adaptations displays a constantly morphing inkblot based on the designs used in the tests.

[157] In the 1999 Sofia Coppola movie The Virgin Suicides the character of Cecilia is given the test[158] and in David Cronenberg's Spider (2002) the Rorschach inkblots are incorporated into the opening of the film.

[159][160] In 2022, a Malayalam language film titled Rorschach was announced with actor Mammootty in the lead role, inspiring queries and discussion in social media about the test.