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Brief Symptom Inventory (BSI) - Subject Baseline

This measure appears in the following time-points: Baseline.

Related Construct

Description of Measure

The Brief Symptom Inventory (BSI; Derogatis & Melisaratos, 1983) is a 53-item self-report inventory in which participants rate the extent to which they have been bothered (0 ="not at all" to 4="extremely") in the past week by various symptoms. The BSI has nine subscales designed to assess individual symptom groups: somatization (SOM, e.g., "Faintness or dizziness"), obsessive-compulsive (OC, e.g., "Having to check and double-check what you do"), interpersonal sensitivity (IS, e.g., "Feeling inferior to others"), depression (DEP, e.g., "Feeling no interest in things"), anxiety (ANX, e.g., "Feeling tense or keyed up"), hostility (HOS, e.g., "Having urges to break or smash things"), phobic anxiety (PHB, e.g., "Feeling uneasy in crowds, such as shopping or at a movie"), paranoid ideation (PAR, e.g., "Others not giving you proper credit for your achievements"), and psychoticism (PSY, e.g., "The idea that something is wrong with your mind"). The BSI also includes three scales that capture global psychological distress.

Confirmatory factor analysis was conducted with the Pathways sample, examining each subscale as a single factor solution. The values generated from this analysis are as follows:

Multiple subscale scores are thus provided:

We also have available two variables which are associated with the clinical status of the case.

Caution should be exercised when using the subscales scores for the BSI. Most researchers agree that the BSI is an appropriate measure of general psychopathology and psychological distress (for a summary of the literature on this issue, see Skeem, Schubert, Odgers, Mulvey, Gardner & Lidz (2006). Reliability for the Global Severity Index (GSI) is reported as .95 (Derogatis & Melisaratos, 1983). However, its utility at the discrete symptom or item level (subscales) is questionable (cf. Benishek, et.al., 1998). Specifically, multiple factor analytic and other studies suggest that the discriminant validity of several BSI subscales is poor. Four factors repeatedly emerge across most factor analytic studies, and the general consensus of the research in this area at the time of this entry (06/05) is that four of the subscales can therefore be used with confidence in their validity: depression, anxiety, somatization and hostility.

In summary, subscales with an acceptable fit include: Somatization, phobia, paranoia and psychoticism. The fit for obsessive-compulsive is questionable while the fit for depression, anxiety and hostility is not acceptable. Testing was also completed for nesting models. In this analysis, the nine factor model represents a statistically significant improvement over the one factor BSI model. However, given the degree of misfit in the nine individual models and the fact that only 4 of the subscales obtain an acceptable fit, it is likely that the nine factor model specified here is not the best solution for this set of items. Also, it should be noted that the fit statistics for these models are very sensitive to sample size. Thus, while the fit is adequate (RMSEA=.07), it is not ideal. These findings support the general research about the potential problems of using these subscale scores alone and the lack of congruence between the results of earlier investigations and the results seen in this sample lend extra caution.

We provide a variable to indicate the clinical significance of each of the subscale scores. The BSI manual (p. 32) describes a set of operational rules for determining whether a subject's scores are elevated to the point of clinical concern. According to the manual, a clinically significant score can be reached in two ways:

The Pathways study identified cases with clinically significant BSI scores using the following steps: