Select an assessment tool from the list of assessments (see attachment). Explore the literature to identify another assessment tool that is purported to measure the same construct(s). Compare the tools on the basis of key test measurement concepts of reliability and validity. Describe the interpretation of results of each test based on standard statistical methods and procedures including scales of measurement, measures of central tendency, indices of variability, shapes and types of distributions, and correlations as they apply to each assessment tool. Evaluate which assessment tool is a stronger assessment instrument using measurement concepts based upon the review of the literature.
APA formatting, APA (6th Edition) Style.
The two assessment tools selected are the Symptoms Checklist-90 Revised (SCL-90-R), and the General Health Questionnaire (GHQ).
The Symptoms Checklist-90-R (SCL-90-R, Derogatis, 1994) is a 90-item self report instrument designed to measure psychological and psychiatric symptoms. The SCL-90-R is a revised and updated version of the Hopkins Symptoms checklist. This instrument is designed to assess psychological symptoms and symptoms of psychopathology. According to Derogatis, the SCL-90-R measures symptoms of: (a) Obsessive Compulsive, (b) Interpersonal sensitivity, (c) depression, (d) anxiety, (e) hostility, (f) phobic anxiety, (g) paranoid ideation, & (h) psychoticism (as cited in Groth-Marnat, 2003). Studies show that the SCL-90-R has good internal reliability (a=.79) for paranoid ideation, and (a=.90) for depression (Horowitz et al., 1988 as cited in Dawes, Loxron, Hides, Kavanaugh, & Mattick, 2002). In terms of validity, the SCL-90-R and provides a one-dimensional measure of psychological distress.
The General Health Questionnaire (GHQ, Goldberg, & Williams (1988) is a self-administered scoring test that is sensitive to the presence of psychological symptoms. There are several versions of the GHQ including the original GHQ-60; the GHQ-28; the GHQ-30, and the GHQ-12. Research indicates that the GHQ -12 and GHQ-28 is used more often than the original version. The GHQ-28 provides 4 specific subscales that are similar to the SCL-90-R: Somatic symptoms, anxiety, insomnia, social dysfunction, and severe depression (Dawes et al., 2002). Some of the item constructs measured by the SCL-90-R and the GHQ are lack of confidence, worry, depression, unhappiness and lack of concentration. This paper will present studies that compare these two instruments--the GHQ and the SCL-90-R. From this perspective -of the following studies the utility, reliability, and validity of the GHQ (Goldberg, William, 1974), and the SCL-90-R (Derogatis, l974) will be examined in the literature focused on the similarities and capability of the two instruments to detect psychological disorders.
(1) GHQ-12, GHQ-28 and SCL-90-R
In the first study examined, Vallejo, Mañanes, Comeche, & Díaz (2008) compared the Symptom checklist (SCL-90-R) with the General Health Questionnaire (GHQ, Goldberg, l972, 978). They investigated the factor structure (i.e. what is being measured)of the GHQ-12 by generating two revised versions of the GHQ, the GHQ-12 and the GHQ-28. The results revealed that GHQ-12 had a one-dimensional structure after controlling for wording effects. In other words, the results were a function of whether the words were either positive or negative. Thus, according to Vallejo et al, the effects of wording have tended to confound the results of factor analysis which have led to many conclusions that the GHQ-12 is a multi-dimensional measure. The significance of this study is based on the recommendations by Vallejo et al that the GHQ-12 be considered and used as a one-dimensional instrument for evaluating general mental health. Thus, when compared with the SCl-90-R, both instruments are useful for detecting psychological disorders when used in combination.
(2) GHQ 36, GHQ-36, and the SCL-90
In a study conducted by Holi, Marttunen, & Aalberg (2003) the GHQ-36, the GHQ-12 and the SCL-90 were compared to determine its usefulness as a screening instrument for psychological disorders in a Finnish population (N=522). All three instruments were administered utilizing the external criteria, psychiatric patients (n=207), and to a community sample (n=315). To test the relationship between the GHQ and the patient or community sample, the GHQ performance was stated in terms of its sensitivity and ...
This solution compares assessment instruments that measure similar constructs.