The Children’s Global Assessment Scale (CGAS) (Shaffer et al. 1983) is one of the most widely used measures of the overall severity of disturbance in children. It is a unidimensional (global) measure of social and psychiatric functioning for children ages 4–16 years. The CGAS is based on an adaptation of the Global Assessment Scale (GAS) for adults and can be used as an indicator of need for clinical services, a marker for the impact of treatment, or a single index of impairment in epidemiological studies.

The CES-D is a 20-item, self-report depression scale. Items refer to the frequency of symptoms during last week. It can also be administered as a structured interview. The CES-D is a brief questionnaire that assesses the frequency and duration of the symptoms associated with depression. Studies with alcohol and drug abusers have shown the scale to be a reliable and valid measure of depressed feelings in these groups. CES-D also suitable for measuring change and improvements in depression following treatment. It has been used with both males and females in general population surveys and in various clinical samples, including alcohol and drug abusers. The CES-D has been adapted for use with children. The scale has also been validated for use with adolescents, the elderly, and a number of different ethnic groups. As with other self-assessed depression scales, the CES-D should not be viewed as a diagnostic tool, but rather as a screening test to identify individuals or groups at risk for depression.

The Brief Symptom Inventory (BSI) is a multidimensional symptom inventory designed to reflect psychological symptom patterns of psychiatric and medical patients. This 53-item self-report is the short form of the SCL-90-R instrument. Like the SCL-90-R instrument, the BSI can be useful in initial evaluation of patients at intake as an objective method of screening for psychological problems. The BSI instrument is especially appropriate in clinical situations where debilitation results in reduced attention and endurance, in research with limited interview schedules, and in outpatient clinics where testing procedures demand brevity. The BSI instrument is also frequently used in measuring patient progress during treatment or in the assessment of treatment outcomes. Completion time is 8-10 minutes. This instrument is useful in tracking changes in reported psychopathology over time. It gives specific indicators of a variety of forms of psychopathology and overall relative severity of psychopathology. The BSI 18 (Derogatis, 2000) is a brief, easy-to-administer, abbreviated version of the BSI and the SCL. It takes 4 minutes to administer and complete, and measures somatization, depression, and anxiety in both inpatient and community settings. It is used primarily to monitor mental health status during hospitalization and aftercare for patients with chronic conditions.

The Beck Depression Inventory was developed to measure the behavioral manifestations of depression in adolescents and adults. It was designed to standardize the assessment of depression severity in order to monitor change over time or to simply describe the illness. The BDI is a 21-item test presented in multiple choice format which is used to measure presence and degree of depression in adolescents and adults. Each of the 21-items of the BDI attempts to assess a specific symptom or attitude associated with depression, that association being consistent with descriptions of the depression contained in the psychiatric literature. The test takes 5-10 minutes to complete. Reading age of about 10 is required for a patient who is self-administering the test. In 1978, the scale was revised (BDI-IA) to eliminate duplicate severity descriptors and to reword certain items. In addition, the time frame for assessment was lengthened to the "last week, including today." In 1996, a new version of the BDI (BDI-II) with a modification of items to reflect DSM-IV criteria and to simplify wording was published. The time frame was extended to include the "last 2 weeks." The BDI-II is a 21 item measure (Beck et al., 1996) self-report measure. Although psychometric data presented in the manual for the new BDI-II look promising, the time frame extension to 2 weeks makes this instrument less useful for assessing patterns of change over time. There is evidence that the BDI-II performs well in treatment-seeking substance abusers.