Fatigue Questionnaire (CIS 20R)

Abstract

The Fatigue Questionnaire (CIS 20R), derived from the longer Checklist Individual Strength (CIS), is a concise, 20-item self-report questionnaire designed to measure the severity and impact of subjective feelings of fatigue experienced over the past two weeks. It utilizes a 7-point Likert scale ranging from “yes, that is true” (1) to “no, that is not true” (7), allowing for nuanced assessment.

The instrument is highly valued in clinical and occupational health research due to its strong psychometric properties, particularly its multidimensional approach to evaluating fatigue across physical and mental domains. It is frequently employed to screen for excessive fatigue in working populations and to monitor symptoms in conditions such as Chronic Fatigue Syndrome.

Keywords

Fatigue Questionnaire, CIS 20R, Checklist Individual Strength, subjective fatigue, occupational health, psychometric properties, chronic fatigue, working population, self-report scale

Authors

Beurskens, A. J., Bültmann, U., Kant, I., Vercoulen, J. H., Bleijenberg, G., Swaen, G M H.

Purpose

The primary purpose of the CIS 20R is to provide a reliable and validated measure of the subjective experience of fatigue. It aims to quantify the level of fatigue experienced by an individual, focusing specifically on the impact of these symptoms over a recent two-week period.

This scale is crucial for research investigating the prevalence of fatigue in various settings, particularly within the working population, allowing researchers and clinicians to identify individuals suffering from high levels of physical and mental exhaustion that may affect work performance and quality of life. The 20-item structure provides a balance between comprehensive assessment and ease of administration.

Construct

The CIS 20R measures the multidimensional construct of subjective fatigue. Unlike scales that focus purely on physical exhaustion, the CIS 20R assesses fatigue across four distinct, yet related, subscales. These dimensions capture the complexity of how fatigue manifests in daily life.

The four core dimensions typically measured by the CIS 20R are: General Fatigue (items related to overall tiredness), Reduced Concentration (items related to cognitive effort and focus), Reduced Motivation (items reflecting lack of desire or initiative), and Reduced Physical Activity (items concerning physical capacity and exhaustion).

Validity

Studies examining the CIS 20R have consistently demonstrated strong evidence of its validity. Content validity is ensured by covering the key dimensions of subjective fatigue, as recognized in clinical practice and research.

Furthermore, convergent validity has been established through positive correlations with other widely accepted fatigue measures, such as the Sickness Impact Profile (SIP) and the Multidimensional Fatigue Inventory (MFI). Discriminant validity is evidenced by the scale’s ability to differentiate between healthy control groups, individuals with mild fatigue, and those suffering from severe chronic fatigue conditions.

Reliability

The CIS 20R exhibits high levels of internal consistency, confirming its reliability across diverse populations. Internal consistency, measured by Cronbach’s alpha, typically exceeds 0.90 for the total score, indicating excellent homogeneity among the 20 items in measuring the overall fatigue construct.

Reliability testing has also shown good test-retest reliability over short intervals, suggesting the scale provides stable measurements of fatigue levels, provided the underlying condition does not significantly change. This stability makes the CIS 20R a valuable tool for monitoring treatment efficacy or symptom progression over time.

Factor Analysis

Factor analysis studies conducted on the CIS 20R generally support a multidimensional structure. While some early research suggested a dominant single factor (General Fatigue), subsequent confirmatory factor analysis (CFA) often validates the hypothesized four-factor model (General Fatigue, Concentration, Motivation, and Physical Activity).

The four-factor structure aligns with the theoretical understanding that fatigue is not a monolithic construct but rather a syndrome composed of distinct cognitive, motivational, and physical components. This robust factor structure enhances the scale’s utility for differential diagnosis and targeted intervention planning in occupational health and clinical psychology.

Instrument

Test Type: Self-report Questionnaire

Format: 20 items, scored on a 7-point Likert scale (1 to 7)

Language Available: Dutch (Original), English, German, and multiple other validated translations.

Population Group: Clinical populations (e.g., CFS patients), general population, and working populations.

Age Group: Adults (typically 18 years and older)

Population Details: Originally validated specifically among working people to assess fatigue in an occupational context, where high fatigue levels can predict sickness absence and reduced productivity.

Test Methodology: Respondents rate the extent to which each statement applies to their feelings over the preceding two weeks. Total scores range from 20 to 140. Higher scores indicate greater levels of fatigue. Specific items are reverse scored to mitigate response bias.

Keywords

Checklist Individual Strength 20R, psychometrics, Likert scale, physical exhaustion, cognitive fatigue, chronic illness, symptom assessment, fatigue measurement

Authors

Author ORCID Identifier: Information not provided in source content.

Affiliation Email addresses: Information not provided in source content.

Correspondence Address: Information not provided in source content.

Permissions & Fee and Test Year

The CIS 20R is widely used in academic and clinical settings. Researchers should consult the primary author or official distribution channels regarding specific licensing and usage fees. The key validation study used to establish the scale’s validity among working people was published in 2000.

The original PDF of the article detailing the validity of the questionnaire can be downloaded here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1739950/pdf/v057p00353.pdf

Reference’s

• Beurskens, A. J., Bültmann, U., Kant, I., Vercoulen, J. H., Bleijenberg, G., Swaen, G M H. (2000). Fatigue among working people: validity of a questionnaire measure. Occupational Environmental Medicine, 57(5), 353–357.

Items of the Fatigue Questionnaire (CIS 20R)

Instructions: During the past two weeks. Respondents use a 7-point scale: yes, that is true (1) to no, that is not true (7).

1. I feel tired*
2. I feel very active
3. Thinking requires effort*
4. Physically I feel exhausted*
5. I feel like doing all kinds of nice things
6. I feel fit
7. I do quite a lot within a day
8. When I am doing something, I can concentrate quite well
9. I feel weak*
10. I don’t do much during the day*
11. I can concentrate well
12. I feel rested
13. I have trouble concentrating*
14. Physically I feel I am in a bad condition*
15. I am full of plans
16. I get tired very quickly*
17. I have a low output*
18. I feel no desire to do anything*
19. My thoughts easily wander*
20. Physically I feel in a good shape

* Reverse scored items.