{4:00 minutes to read} The Methodology of Forensic Evaluations.

Forensic evaluations differ with respect to the focus of the questions they seek to answer. For instance, in a custody evaluation, the focus is to assess the fit between a particular parent and a child. In contrast, in evaluations designed to assess competency to stand trial, the focus is to assess whether a party is able to understand the nature of the proceedings against him/her and his/her ability to assist the attorney.  

Although forensic evaluations differ with respect to the questions they seek to answer, the underlying methodology is the same. All forensic evaluations start with the presumption that the parties to be evaluated come with an agenda and because of it, their presentation is likely to be biased. To offset this tendency, all forensic evaluations seek to complement the data gathered in a clinical interview with additional data. There are two main sources of data used to complement the clinical data obtained during the course of the interviews. One source of such data is the use of psychological testing and the other one is the use of collateral data. Through the use of a multi-pronged methodology (interviews, psychological testing, collateral data) clinicians hope to increase “convergent validity” that is, reaching the same conclusions through the employment of diverse and complementary methodology.

In the next few articles, I will focus on the cornerstones of forensic assessments: the use of psychological testing and the use of collateral data in forensic evaluations.   

Psychological testing

As noted, testing is an important way to complement clinical data.  

Because of the “scrutiny” of testing in court, the evaluator needs to use measures that are grounded in objectiveness and have good psychometric properties (good reliability and good validity). Reliability refers to the ability to reproduce the same result consistently. Validity assesses whether the test measures what it purports to measure (the correct “construct”).

One of the main problems with the use of psychological testing in forensic assessment pertains to specificity. It is often the case in a forensic assessment that some instruments are used because they are very common but do not necessarily have a direct relationship to the psycho-legal construct that is being assessed. For instance, the Minnesota Multiphasic Personality Inventory, or MMPI 2, is the most frequently used psychological instrument in forensic evaluations.

The MMPI-2 assesses psychopathology and the presence of behavioral patterns. Like in other types of forensic evaluations, the MMPI-2 is commonly used in custody evaluations. It is important to note that in custody evaluations, the key construct of interest is that of Parental Capacity yet the MMPI-2 does not assess parental capacity but rather assesses the presence of pathology. In using the MMPI-2 in a custody evaluation, therefore, one relies on a tool that does not have sufficient specificity, that is, it does not directly assess the construct of interest (parental capacity).  

This does not disqualify the use of MMPI-2 in custody evaluations, however, such use should be based on the caveat that the use of the MMPI-2 might be relevant to custody evaluations only insofar as one suspects the presence of mental illness in one of the parents and can link the presence of such pathology to specific parenting impairments.

To summarize, in forensic evaluations, it is vitally important to have an instrument that specifically addresses the target construct (parental capacity, in the case of custody evaluation).

In the next article, we will discuss additional aspects of psychological testing in forensic evaluations.

Dr. Alberto Yohananoff
NYC Forensics
dryohananoff@nycforensics.com
P: (646) 284-5600
F: (212) 706-9136

Posted in Forensic Evaluations