Brief overview of the SCL-90 Overview

The SCL-90 is a 90-item self-report questionnaire designed to assess the severity and pattern of psychological symptoms across domains such as mood, anxiety, obsessive thoughts, interpersonal sensitivity, and somatic complaints. People rate how much each symptom has distressed them on a graded scale, providing an overall picture of their psychological status across several dimensions.

The SCL-90 is mainly used in clinical, research, and counseling settings for screening, tracking treatment progress, and examining changes in symptoms over time. Completing the questionnaire typically takes between 12 and 20 minutes.

What is the SCL-90? What is SCL-90?

The SCL-90 (Symptom Checklist-90) was developed by Leonard R. Derogatis and colleagues and is one of the most widely used multidimensional instruments for assessing psychological symptoms. The commonly used version is often referred to as the SCL-90-R.

The instrument focuses on psychological distress and symptom severity. Rather than providing categorical diagnoses, it shows the overall pattern of a person’s symptoms across multiple domains.

• Instrument type: multidimensional self-report questionnaire
• Typical use: clinical practice, research, counseling, and mental health services
• Response format: 5-point rating scale from “not at all” to “extremely”

What does the SCL-90 measure and who is it for? Domains & Target Group

The SCL-90 is designed to assess a wide range of psychological symptoms and evaluates nine core dimensions:

• Somatization
• Obsessive–Compulsive
• Interpersonal Sensitivity
• Depression
• Anxiety
• Hostility
• Phobic Anxiety
• Paranoid Ideation
• Psychoticism

The test is generally suitable for older adolescents and adults and can be used with both clinical populations (therapy clients, psychiatric patients) and non-clinical samples (university research and community studies).

Applications of the SCL-90 Applications

SCL-90 results can be useful in a variety of situations:

• Initial screening of psychological symptoms in mental health service users
• Estimating overall psychological distress and identifying domains that need more attention
• Monitoring treatment progress by comparing symptom levels before and after interventions
• Using symptom scores as variables in psychological research alongside other constructs
• Examining patterns of symptom comorbidity across different clinical or demographic groups

How is the SCL-90 administered? Administration

The SCL-90 consists of 90 items, each describing a specific symptom. Respondents rate how much each symptom has distressed them over the past few weeks on a 5-point scale.

• Number of items: 90
• Response format: 5-point scale from 0 (not at all) to 4 (extremely)
• Administration: self-report, paper or electronic
• Estimated time: about 12–20 minutes

Before you take the test Before You Start

• Try to answer the questions in a relatively quiet environment without major distractions.
• It is best to complete the questionnaire in one sitting without long interruptions.
• Base your responses on your general and typical state over the past few weeks, not just a single exceptional day.
• Honest responses based on your real experience help build an accurate picture of your symptom pattern.
• For each item, mark your first impression and feeling rather than overthinking the question.

Interpreting SCL-90 results Interpretation

SCL-90 scores are usually reported as dimension scores for each of the nine symptom domains, along with global indices such as GSI, PST, and PSDI. Higher scores on a given dimension or global index indicate higher levels of distress or more frequent symptoms in that area.

In interpretation, both the overall level of distress and the pattern of scores across domains are important. For example, simultaneous elevations in depression, anxiety, and interpersonal sensitivity may point to emotional strain combined with relational difficulties.

However, the SCL-90 alone is not sufficient to make formal psychiatric diagnoses. Results should be interpreted alongside clinical interviews and other information by a qualified mental health professional.

• High scores indicate increased symptom levels but do not automatically mean “definite risk” or a diagnosis.
• Relying on a single score without considering the person’s life context can be misleading.
• Ethically, test results should be used to support responsible, helpful decisions and not to harm or stigmatize.

SCL-90 forms and versions Forms & Versions

The original instrument was developed as the SCL-90, and several revised and shorter versions have been derived from it, including:

• SCL-90-R: revised version with the final 9-factor structure and global indices
• BSI (Brief Symptom Inventory): a shorter form with fewer items
• Translated and normed versions in different languages and cultures

In many countries, local versions have been normed so that scores can be compared to relevant reference groups. Choosing the appropriate version should be based on the purpose of use, time constraints, and characteristics of the target population.

Symptom dimensions measured by the SCL-90 Symptom Map

The SCL-90 provides a multidimensional map of psychological symptoms that can be thought of as a network spanning three broad areas: inner experience (emotional and cognitive), the body (somatic sensations), and relationships with others (interpersonal aspects).

Frequently asked questions about the SCL-90 FAQ

Ethical considerations when using the SCL-90 Ethical Considerations

• Responses must be kept confidential and used only for legitimate professional or research purposes.
• Test results should not be used to label, judge, or stigmatize individuals.
• Participants should know they can stop answering if they feel uncomfortable.
• Interpretation and feedback, especially when symptoms are severe, should be offered with sensitivity and respect, ideally along with referral options for professional help.
• Using the SCL-90 in high-stakes decisions (for example employment or education) requires strict adherence to professional ethics and clear communication about purposes and limitations.

Further reading on the SCL-90 References

For a deeper understanding of the SCL-90 and its psychometric properties, the following sources may be helpful:

• Derogatis, L. R. (1994). SCL-90-R: Administration, Scoring, and Procedures Manual.
• Articles in psychiatric and clinical psychology journals examining the reliability and validity of the SCL-90 in various populations.
• Databases such as PubMed, PsycINFO, and Google Scholar for up-to-date research on this instrument.

When using the SCL-90 in research, it is essential to use a valid edition, respect copyright and licensing requirements, and follow the official administration and scoring guidelines.