MMPI F(Back) Scale - Cross-Examining Psych Doctors, Tip #105

Every validity and clinical scale performance on the Minnesota Multiphasic Personality Inventory (MMPI) is described with a T-Score.  All T-Scores on the validity scales and the clinical scales on the MMPI have a mean of 50 and a standard deviation of 10.  In this regard, it should be noted that it is universally accepted that T-Scores of 65 or larger are clinically significant or interpretable.  There are many books and journal articles on the MMPI that make this point.  In this regard, one of the validity scales on the MMPI is the F(Back) Scale or what is often called the F(b) Scale.  The F(b) Scale is a validity scale that is analogous to the F Scale, except that the items on the F(b) Scale are placed in the last half of the test, hence the name “F(b)” representing an F-like scale at the back of the test.  A score of 65 or higher on the F(b) Scale is indicative of a high probability the patient was trying to appear to have symptoms that do not exist.  In these situations, you should look for the place in the doctor’s report where he/she discussed that the patient’s F(b) Scale score showed they were attempting to simulate symptoms, or what some mental health practitioners would call “faking” or “Malingering.”