Description of the Questionnaire

The Symptom Checklist-90-Revised (SCL-90-R) is a self-administered psychometric tool designed to assess a wide range of psychological problems and symptoms of psychopathology. It consists of 90 questions referring to psychological and somatic symptoms that examine the individual’s mental state over the past week. Participants are asked to rate each symptom on a five-point scale, ranging from 0 (not at all) to 4 (extremely), based on the intensity of the symptom.

Data Analysis and Use

The data collected from the SCL-90-R is analyzed both qualitatively and quantitatively, providing an overall picture of the respondent’s psychological state. The questionnaire includes nine primary dimensions: Somatization, Obsessive-Compulsive Symptoms, Interpersonal Sensitivity, Depression, Anxiety, Hostility, Phobic Anxiety, Paranoid Ideation, and Psychoticism. Additionally, it yields three global indices: the Global Severity Index (GSI), which reflects the overall level of psychological distress; the Positive Symptom Distress Index (PSDI), which measures the average intensity of reported symptoms; and the Positive Symptom Total (PST), which indicates the total number of reported symptoms. The data are widely used in clinical practice to assess mental health, aid in differential diagnosis, monitor therapeutic progress, and support research into patterns of psychopathology.

Purpose

The main purpose of the SCL-90-R is the objective recording of the intensity and frequency of psychological symptoms in both clinical and non-clinical populations. The tool contributes to understanding the emotional and mental state of the individual and supports the process of clinical evaluation and decision-making. It is not intended to provide diagnoses but functions as an auxiliary tool for mental health professionals.

Scoring

Scoring of the SCL-90-R is based on the responses provided for each item using the five-point scale, where 0 means “not at all” and 4 means “extremely.” Separate scores are calculated for each of the nine dimensions, as well as for the three global indices. Interpretation of the results is based on established thresholds and normative data derived from general population samples. Higher scores indicate greater symptom intensity and increased psychological burden. Proper interpretation requires professional training and is conducted exclusively by qualified personnel.

References

Derogatis, L. R. (1994). SCL-90-R: Administration, scoring and procedures manual. Minneapolis: National Computer Systems. Derogatis, L. R., & Cleary, P. A. (1977). Confirmation of the dimensional structure of the SCL-90: A study in construct validation. Journal of Clinical Psychology, 33(4), 981–989. Boulet, J., & Boss, M. W. (1991). Reliability and validity of the Brief Symptom Inventory. Psychological Assessment: A Journal of Consulting and Clinical Psychology, 3(3), 433–437. Platella, M. & Frantzi, A. (2003). Psychometric evaluation of the SCL-90-R in the Greek population. Psychiatry, 14(3), 202–213.