Perceived Stress Scale PSS

Abstract

The Perceived Stress Scale (PSS) is a highly respected and widely utilized psychological instrument developed by Cohen, Kamarck, and Mermelstein in 1983. Its primary function is to quantify the degree to which an individual subjectively appraises situations in their life as stressful. The scale focuses on the frequency with which respondents experience feelings of being overloaded, and perceive their daily existence as both unpredictable and uncontrollable—the three foundational dimensions of the subjective stress experience. While the original version, the PSS14, comprised 14 items, shorter validated iterations such as the 10-item PSS10 and a four-item scale are frequently employed in research, all demonstrating robust psychometric properties suitable for diverse applications.

Keywords

Perceived Stress Scale, PSS, stress measurement, psychological assessment, self-report scale, Cohen, psychometrics, stress appraisal, subjective stress, PSS10.

Authors

Sheldon Cohen, Tom Kamarck, Richard Mermelstein

Purpose

The core purpose of the Perceived Stress Scale is to serve as an efficient, economical, and reliable tool for assessing global levels of perceived stress, particularly within research and epidemiological settings. Unlike measures that focus on specific stressful life events or clinical symptomology, the PSS is designed to capture the generalized affective and cognitive appraisal of stress experienced by the individual over the preceding month.

The instrument measures the extent to which an individual views their current life circumstances as threatening, difficult to manage, or exceeding their available coping resources. Its brevity and ease of administration have made it invaluable for large-scale studies where rapid, yet reliable, assessment of subjective stress is necessary. Crucially, the authors intentionally designed the PSS to be used freely for research purposes, significantly contributing to its widespread adoption across various disciplines studying health, behavior, and adaptation.

Construct

The PSS is designed to measure the psychological construct of perceived stress, which is defined as the subjective feeling that arises from the appraisal of life situations. This construct is distinct from objective measures of stress (e.g., counting life events) because it focuses on the individual’s internal interpretation of external demands—specifically, how uncontrollable and overloaded they feel in response to these demands.

The scale operationalizes the construct of perceived stress through three fundamental components:

• Unpredictability: This relates to the feeling of being blindsided or surprised by unexpected negative events in one’s life.
• Uncontrollability: This component addresses the subjective sense of being unable to manage, influence, or cope with important things or demands.
• Overload: This refers to the perception that difficulties, responsibilities, or demands are accumulating rapidly and exceeding the individual’s capacity to cope.

By focusing on these affective and cognitive responses, the PSS provides a robust measure of current stress levels that reflects how an individual is actively engaging with and interpreting their environment.

Validity

The validity of the PSS is strongly supported by consistent empirical evidence demonstrating its relationship with other established measures of well-being, psychological distress, and health outcomes. Convergent validity is particularly well-established, evidenced by the finding that PSS scores correlate moderately and meaningfully with responses on other standardized measures of appraised stress and anxiety, confirming that the scale successfully measures the intended construct of subjective stress appraisal.

Beyond its initial context, the PSS has demonstrated significant utility through extensive cross-cultural validation studies. Successful validation efforts have been conducted globally, including in populations in Australia, Japan, and Greece. These studies consistently report satisfactory psychometric properties, suggesting that the scale is reliable and culturally adaptable for assessing subjective stress across diverse societal and linguistic contexts.

Reliability

The internal consistency of the PSS is generally considered acceptable to good, a metric typically assessed using Cronbach’s alpha coefficients. These coefficients indicate the degree to which items within the scale measure the same underlying construct.

• The original PSS14 version reported acceptable internal consistency, with a Cronbach’s alpha coefficient of .75.
• The abbreviated PSS10 version demonstrated slightly superior reliability, reporting a Cronbach’s alpha of .78, confirming that the exclusion of less effective items enhanced the scale’s psychometric quality.

While the internal consistency is well-documented, test-retest reliability, which measures the stability of scores over time, was not a focus of the foundational studies. However, the scale’s extensive use in longitudinal research implies that its scores possess sufficient stability to reliably measure perceived stress levels over short to moderate assessment intervals.

Factor Analysis

The development of the PSS involved rigorous structural examination through factor analysis applied to the initial 14 items (PSS14). Researchers employed a principal components method coupled with a Varimax rotation to discern the latent structure of the perceived stress construct.

This analysis revealed a strong primary underlying dimension, interpreted as global perceived stress, with ten items loading positively at a coefficient of .48 or higher on the first factor. Conversely, four items exhibited low loadings (below .39). Based on these findings, the refined PSS10 version was created by systematically eliminating the four poorly loading items. This crucial refinement resulted in a more focused and psychometrically sound instrument that better captures the intended construct with improved efficiency.

Normative data derived from the initial validation samples provide essential benchmarks for interpretation. The reported statistics for the different versions included:

• PSS14: Mean = 19.62 (SD = 7.49)
• PSS10: Mean = 13.02 (SD = 6.35)

Instrument

Test Type: Self-report questionnaire

Format: Likert scale (5-point frequency scale, ranging from 0=never to 4=very often)

Language Available: English (Original), with numerous validated translations available globally.

Population Group: General population, primarily adults and adolescents.

Age Group: Typically utilized with individuals aged 16 and older.

Population Details: The scale was initially developed in the USA and assumes respondents possess a minimum of a high school education to ensure adequate reading comprehension for the items.

Test Methodology: Respondents are instructed to reflect on their feelings and thoughts over the past month. They indicate the frequency with which they experienced various stressful situations or associated reactions. Scoring is achieved by summing the responses, often requiring the reversal of positively worded items to align the direction of scoring with overall perceived stress levels.

Keywords

Cohen, Kamarck, Mermelstein, psychological measurement, stress evaluation, subjective stress, PSS10, PSS14, principal components analysis, reliability, validity, factor analysis.

Authors

Author ORCID Identifier: Not publicly provided in source material.

Affiliation Email addresses: Not publicly provided in source material.

Correspondence Address: Not publicly provided in source material.

Permissions & Fee and Test Year

The Perceived Stress Scale was officially developed and published in 1983 by Sheldon Cohen, Tom Kamarck, and Richard Mermelstein. It was explicitly created as an economical and universally accessible tool for use in scientific research.

Permissions: The PSS is freely available for non-commercial and research applications. No formal permission or licensing fee is required for its use. The complete scale items are widely accessible online and were included in the appendix of the original 1983 publication.

The instrument (specifically the PSS-10) can also be found on page 114 of the dissertation titled, “Differences in Perceived Stress‚ Affect‚ Anxiety‚ and Coping Ability Among College Students in Physical Education Courses” by Rachel Permuth Levine (2007). The original PDF can be downloaded here: http://drum.lib.umd.edu/bitstream/1903/6811/1/umi-umd-4299.pdf

Reference’s

The following references were foundational to the development, validation, and early application of the Perceived Stress Scale:

• Cohen‚ S.‚ Kamarck‚ T.‚ Mermelstein‚ R. (1983). A global measure of perceived stress. Journal of Health and Social Behavior‚ 24(4)‚ 385-396.
• Cohen‚ S.‚ Kessler‚ R.‚ & Gordon‚ L. (1995). Measuring Stress. Oxford: Oxford University Press‚ Inc.
• Cole‚ S. R. (1999). Assessment of Differential Item Functioning in the Perceived Stress Scale-10. Journal of Epidemiology and Community Health‚ 53‚ 319-320.
• Levine‚ Rachel Permuth. (2007). Differences in Perceived Stress‚ Affect‚ Anxiety‚ and Coping Ability Among College Students in Physical Education Courses. University of Maryland‚ College Park. PhD Dissertation.

Items of the Perceived Stress Scale PSS

IMPORTANT: The following scale items must be preserved in their original language and must not be changed in any way.

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1. In the last month‚ how often have you been upset because of something that happened unexpectedly?

2. In the last month‚ how often have you felt that you were unable to control the important things in your life?

3. In the last month‚ how often have you felt nervous and "stressed"?

4. In the last month‚ how often have you felt confident about your ability to handle your personal problems?

5. In the last month‚ how often have you felt that things were going your way?

6. In the last month‚ how often have you found that you could not cope with all the things that you had to do?

7. In the last month‚ how often have you been able to control irritations in your life?

8. In the last month‚ how often have you felt that you were on top of things?

9. In the last month‚ how often have you been angered because of things that were outside of your control?

10. In the last month‚ how often have you felt difficulties were piling up so high that you could not overcome them?

Response Scale: 0=never; 1=almost never; 2=sometimes; 3=fairly often; 4=very often