By personality is meant all the abiding traits of character that constitute an individual’s potential to respond in particular ways to circumstances. All physicians are aware of how much information they must acquire through several interviews with the patient and from independent sources before they can have much confidence in their diagnostic opinion on personality. Tests that could elucidate personality more accurately and more rapidly would be useful. Two alternative approaches have been developed, “projective” tests and questionnaires. Each approach has raised particular problems.
Projective Test of Personality
In the so-called projective tests of personality ambiguous situations are set before the patient, and his responses are recorded. Thus he is presented with sentences to complete, a picture to interpret, or in the most well known projective test, he is presented with a standardized set of ink blots and he is asked to describe the forms that he can recognize within them. Since there is nothing in the situations themselves that force any particular response, the responses of the patient are thought to derive from his personal predilections and inner needs, drives, and conflicts. This seems logical. But logic is not the essential criterion for a test intended to aid the clinical examination. It must be demonstrated that the responses on projective tests provide a measurement with sufficient reliability to make these tests valid instruments for the study of personality. This remains to be done.Certain features of a patient can be expected to be seen in any set of his responses.
For instance, overly conscientious persons will tend to be fixed on details, the schizophrenic patient with his disordered thought will demonstrate this feature in distorted expression, and the depressed patient will speak of unhappy themes as he discusses any matter. These features will appear whether the patient is being examined by his doctor or doing a projective test. Until the reliability and validity of projective tests can be demonstrated, it cannot be known whether they are superior to the clinical examination. If they are not superior to the clinical examination, they are of doubtful utility to the physician, and the question of their value is shrouded in controversy.
The other approach to personality measurement is the questionnaire. This was developed from the clinical examination. Since questions are used there to gain information from the patient, it seemed logical that a questionnaire including these and many other questions with answers assessed precisely would improve on the clinical examination. It came as a surprise when tests developed in this fashion proved to be unreliable and invalid. This was demonstrated when different questionnaires intended to probe similar features of personality, such as introversion, did not correlate well with one another, and in fact could give quite opposite impressions of the same person. Questionnaires developed in this fashion proved so misleading that the method fell into disrepute. It was, however, eventually recognized that these early tests gratuitously assumed that questions would be accurately answered by patients.
How to Prepare Personality Test And Personality Test Questions
Consider the question, do you lack self-confidence, yes or no? To presume that a person will understand this question exactly the same way as the examiner intends and that his criterion for a yes or no answer is the same as that of all other people is to presume too much. Also these early tests fai o to consider that many individuals might attempt to show themselves in some more favorable light and therefore not answer questions truthfully.
The most intriguing conceptual advance in the study of personality was the recognition that an objectively truthful answer to questions was not needed for a valid, useful test. In fact, more information can be obtained from observing the patient’s reply to questions than from any belief that the statements they agree to or reject are in themselves accurate descriptions of their personality. The task of building questionnaires changed from finding questions that would display the inner feelings of people to finding questions that would be answered differently by different personality types.
To build such a questionnaire the first step was to gather specific groups of patients together, a group of normal people, a group of anxious patients, a group of hysterical patients, a group of depressed patients, for as many groups as could be differentiated. These patients the criterion groups, were asked a large number of questions and the replies were compared from group to group. The questions which differentiated the groups best would then be collected for the questionnaire. This questionnaire then given to an individual was interpreted not from the content of questions rejected or affirmed but from the number of questions replied to in the same fashion as was followed by one or more of the criterion groups.
Minnesota Multiphasic Personality Inventory (MMPI)
The most useful questionnaire, that has been developed is the Minnesota Multiphasic Personality Inventory (MMPI). The questions in that test have been carefully studied and chosen so that they differentiate to the greatest degree possible with it. Because of the complexity of issues of personality, the numbers of questions needed to derive a profile with this test is 550. It was possible in the MMPI to fit in many questions that give an indication of the tendency of the patient to lie, exaggerate, or misunderstand questions.
The results of the MMPI are expressed as a series of nine scales or dimensions along each of which an individual is placed by means of his responses that correspond to responses of nine criterion groups. These scales were originally derived from clinical groups and given clinical names, i.e., hypochondriasis, depression, hysteria, psychopathic, masculine-feminine dimension, paranoid, psychasthenic, schizophrenic, and manic. Three so-called lie scales are also scored for each test.
The MMPI is a reliable instrument, the accuracy and reproducibility of its readings having been demonstrated in repeated testing of individuals over many years. The validity, of its scales varies. Some of the scales measure the personality characteristics for which they are titled. Scores on the psychopathic and manic scales do correlate with the clinical features intended by these terms. Scores on the schizophrenic and hysterical scales do not correlate well with these clinical disorders but with aspects Of bizarreness and self-dramatization, respectively. These features are not specific to schizophrenic or hysteria. In an effort to avoid these invalid implications, the MMPI scales are no longer referred to by. clinical titles, but by letters derived from the original names.
The tendency to look at specific scales for diagnostic impressions has been replaced by consideration of the “profile,” or pattern of the several scales together, hoping to derive in this way a more global view of personality structure. This approach emphasizes the multidimensional character of personality. It takes advantage of the features of reliability found in this test. But, once again, the establishment of validity for these profiles must be accomplished. This is being attempted by matching the life course of individuals with predictions from the profiles, but work is still in progress.
Current practice is, to find the MMPI useful as a screening and probing instrument that often suggests aspects of personality difficulty that might well be more carefully studied. If knowledge of its validity increases, the MMPI may take a still more important role in clinical medicine.