MMPI vs. MMPI-2

Attribute	MMPI	MMPI-2
Version	Original	Revised
Number of Items	550	567
Administration Time	60-90 minutes	60-90 minutes
Scoring	Hand-scoring or computerized	Hand-scoring or computerized
Normative Sample	Adults aged 18-65	Adults aged 18 and older
Validity Scales	Cannot Say, Lie, Infrequency, Correction	Cannot Say, Lie, Infrequency, Correction
Clinical Scales	10	10
Supplementary Scales	None	15
Content Scales	None	28
Restructured Clinical (RC) Scales	None	42
Reliability	Good	Good
Validity	Good	Good
Psychometric Updates	None	Yes

Introduction

The Minnesota Multiphasic Personality Inventory (MMPI) and its revised version, the MMPI-2, are widely used psychological assessment tools that measure various aspects of an individual's personality and psychopathology. Developed by Hathaway and McKinley in the 1940s, the MMPI has undergone several revisions over the years, with the MMPI-2 being the most recent and widely used version. While both assessments share similarities, they also have distinct attributes that make them unique. This article aims to explore and compare the attributes of the MMPI and MMPI-2.

Test Construction

The MMPI and MMPI-2 share a common foundation in terms of test construction. Both assessments consist of a large number of true/false questions, known as items, that cover a wide range of psychological constructs. These items are designed to assess personality traits, psychopathology, and clinical symptoms. However, the MMPI-2 includes several new items and scales that were not present in the original MMPI, making it more comprehensive and up-to-date in terms of assessing psychopathology.

Normative Samples

Normative samples play a crucial role in the interpretation of test results. The MMPI was normed on a sample of individuals from the general population, including both clinical and non-clinical groups. In contrast, the MMPI-2 was normed on a more recent and larger sample, which included individuals from diverse backgrounds and regions. This updated normative sample enhances the generalizability of the MMPI-2's results and allows for more accurate interpretations across different populations.

Validity Scales

Both the MMPI and MMPI-2 include validity scales that assess the test-taker's response style and the likelihood of providing accurate and valid responses. These scales help identify potential response biases, such as attempts to present oneself in a socially desirable or overly negative manner. However, the MMPI-2 introduced additional validity scales, such as the Variable Response Inconsistency (VRIN) and True Response Inconsistency (TRIN) scales, which further enhance the assessment of response validity.

Clinical Scales

The clinical scales of the MMPI and MMPI-2 are designed to measure various psychopathological constructs and clinical symptoms. Both assessments share several common clinical scales, such as the Depression (D), Hysteria (Hy), and Psychopathic Deviate (Pd) scales. However, the MMPI-2 introduced several new clinical scales, including the Anxiety (ANX), Social Introversion (Si), and Posttraumatic Stress Disorder (PTSD) scales. These additional scales allow for a more comprehensive assessment of psychopathology and clinical symptoms.

Content Scales

Content scales provide additional information about specific psychological constructs and clinical symptoms. The MMPI-2 introduced several new content scales that were not present in the original MMPI. These include scales such as Alcohol/Drug Problem (AAS), Anxiety Related Disorders (ARD), and Type A Behavior Pattern (TAB). These content scales allow for a more detailed assessment of specific areas of concern and provide valuable information for treatment planning and intervention.

Supplementary Scales

Supplementary scales in the MMPI and MMPI-2 provide additional information that may be relevant to the assessment process. These scales include measures of defensiveness, such as the Lie (L) scale, and measures of unusual or atypical responding, such as the Infrequency (F) scale. The MMPI-2 introduced new supplementary scales, such as the Restructured Clinical (RC) scales, which provide a more refined assessment of psychopathology and clinical symptoms.

Administration Time

The administration time for the MMPI and MMPI-2 can vary depending on several factors, including the test-taker's reading ability and response speed. However, in general, the MMPI-2 takes longer to administer compared to the original MMPI. The MMPI-2 consists of 567 items, while the MMPI has 567 items. This difference in item length contributes to the increased administration time of the MMPI-2.

Conclusion

The MMPI and MMPI-2 are valuable psychological assessment tools that provide valuable insights into an individual's personality and psychopathology. While both assessments share similarities in terms of test construction and validity scales, the MMPI-2 offers several improvements and additions, including an updated normative sample, new clinical and content scales, and refined supplementary scales. These attributes make the MMPI-2 a more comprehensive and accurate assessment tool, allowing for a more detailed understanding of an individual's psychological functioning.