Youth Quality of Life Instrument – Short Form (YQOL-SF)

Abstract

The Youth Quality of Life Instrument – Short Form (YQOL-SF) is a brief, 15-item self-report measure designed to assess generic Quality of Life (QOL) among adolescents aged 11 to 18 years. It is applicable to youth both with and without chronic conditions and disabilities. The instrument is structured around four domains: sense of self, social relationships, environment, and general quality of life, reflecting content derived directly from youth input.

The development of the YQOL-SF utilized rigorous psychometric techniques, including Rasch methodology, to ensure robust measurement properties. Its brevity and strong psychometric foundation make it highly suitable for use in group level intervention research aimed at evaluating changes in perceived well-being over time.

Keywords

Quality of Life, Adolescents, Youth, Chronic Conditions, Disability, Rasch methodology, Psychometrics, YQOL-SF, Well-being.

Authors

Patrick DL, Edwards TC.

Purpose

The primary purpose of the YQOL-SF is to serve as an outcome measure in group level intervention research. Its concise 15-item format makes it highly practical for repeated administration and large-scale studies focused on evaluating the effectiveness of programs aimed at improving adolescent well-being.

The YQOL-SF is specifically designed to capture the youth’s own perception of their Quality of Life (QOL), making it a valuable tool for tracking changes in perceived well-being across diverse populations, including those facing chronic conditions and disabilities.

Construct

The YQOL-SF measures perceived generic Quality of Life (QOL) in adolescents. The conceptual model underpinning the instrument was established through semi-structured interviews with 33 youth (ages 11–18) from varied socioeconomic and health backgrounds, ensuring that the construct definition is relevant and authentic to the target population.

The scale is structured around four primary perceptual domains: Sense of Self, Social Relationships, Environment, and General Quality of Life. These domains collectively capture the subjective positive and negative aspects of QOL as experienced by the youth.

Validity

Content validity was secured by establishing items based on definitions provided by the youth themselves during the development phase, ensuring high relevance to the adolescent experience. Construct validity was assessed by testing the instrument against existing measures for adolescent quality of life.

Convergent validity was demonstrated through a significant positive correlation (r = 0.73) between the YQOL-R total perceptual score and the total score of the Munich QOL Questionnaire for Children (KINDL). This strong association confirms that the YQOL-R measures similar aspects of perceived QOL as established tools.

Discriminant validity (or Known Groups validity) was established by examining associations with related but distinct constructs, such as the Children’s Depression Inventory (CDI) (r = -0.58) and the Functional Disability Inventory (FDI) (r = -0.26). Statistical testing confirmed that the YQOL-R correlated significantly higher with the KINDL (QOL measure) than with the CDI (depression measure) or the FDI (disability measure) (t226 = 6.61, p < .05), supporting its ability to distinguish QOL from functional impairment. The validation sample included youth diagnosed with Attention-Deficit/Hyperactivity Disorder (ADHD), depression, and mobility disabilities.

Reliability

The YQOL-SF demonstrates strong internal consistency and acceptable reproducibility. Internal consistency, measured using Cronbach’s alpha, exceeded 0.80 for all four perceptual domains as well as for the total perceptual score (Patrick et al., 2002).

Reproducibility was assessed via one-week test-retest data collected from 46 adolescents without chronic conditions. The intraclass correlation coefficients (ICCs) for the domains were: Self (0.85), Social (0.85), Environment (0.76), and General QOL (0.74). The ICC for the Total Score was 0.78, indicating good stability of measurement over time.

Factor Analysis

Although the source content does not explicitly detail a traditional Exploratory or Confirmatory Factor Analysis (EFA/CFA), the development utilized Rasch methodology to ensure the measurement properties and scaling assumptions of the 15 items. The scale structure was investigated using the Multi-Trait/Multi-Item Analysis program to confirm the appropriateness of the response scale range and the alignment of items within the four defined domains: Self, Social Relationships, Environment, and General QOL.

The application of Rasch methodology is crucial for establishing that the items function correctly along a single underlying dimension (latent trait) within each domain, confirming the validity of summing or averaging the scores.

Instrument

Test Type: Self-report perceptual measure.

Format: 15 items scored on an 11-point Likert-type scale (0 = not at all to 10 = a great deal or completely). Scores are summed and transformed to a 0 to 100 scale.

Language Available: English (assumed primary).

Population Group: Youth/Adolescents.

Age Group: 11–18 years.

Population Details: Youth with and without chronic conditions and disabilities. The instrument is designed for self-administration, requiring approximately 10 minutes to complete, and meets a fourth-grade reading level based on the Homan-Hewitt readability formula.

Test Methodology: Developed using Rasch methodology and informed by extensive qualitative interviews with adolescents.

Keywords

Self-report, Adolescence, Psychometrics, Validation, KINDL, CDI, FDI, Test-retest reliability, Intervention research.

Authors

Author ORCID Identifier: Not specified in source.

Affiliation Email addresses: Not specified in source.

Correspondence Address: Not specified in source.

Permissions & Fee and Test Year

The YQOL-SF was initially developed and validated with key publications appearing in 2002. Information regarding current permission requirements, licensing fees, and availability of the tool should be obtained by contacting the principal authors (Patrick DL or Edwards TC) or their affiliated institutions.

Reference’s

• Edwards, T. C., Huebner, C. E., Connell, F. A., and Patrick, D. L. (2002). Adolescent quality of life, part I: conceptual and measurement model. J Adolesc 25:275-286.
• Patrick, D. L., Edwards, T. C., and Topolski, T. D. (2002). Adolescent quality of life, part II: initial validation of a new instrument. J Adolesc 25:287-300.
• Kovacs, M. (1992). Children’s Depression Inventory (CDI). Multi-Health Systems.
• Ravens-Sieberer, U., and Bullinger, M. (1998). The Munich QOL Questionnaire for Children (KINDL).
• Walker, L. S., and Greene, J. W. (1991). Functional Disability Inventory (FDI).

Items of the Youth Quality of Life Instrument – Short Form (YQOL-SF)

The YQOL-SF uses an 11-point response scale ranging from 0 (Not at all) to 10 (Very Much/Completely).

1. I am able to do most things as well as I want (please circle one number)
2. I feel good about myself (please circle one number)
3. I feel I am important to others (please circle one number)
4. I am pleased with how I look (please circle one number)
5. I feel understood by my parents or guardians (please circle one number)
6. I feel I am getting along with my parents or guardians (please circle one number)
7. I feel alone in my life (please circle one number)
8. I am happy with the friends I have (please circle one number)
9. I feel I can take part in the same activities as others my age (please circle one number)
10. People my age treat me with respect (please circle one number)
11. I feel my life is full of interesting things to do (please circle one number)
12. I look forward to the future (please circle one number)
13. I feel safe when I am at home
14. I feel I am getting a good education
15. I am satisfied with the way my life is now

Steps in Scoring the YQOL-SF

• First, transpose all 15 items to t-scores on a 100-point scale as follows:

t s c o =a c t uraal ws c o –r leo w  eps ot  s s i rb al ews c o r e

r e                                                                     *1 0 0

p o s s i rbal ews c o r ea n g e

SPSS syntax of the following form:

COMPUTE Item1_tscore = ((Item1_score-0)/10)*100.

This transformation converts the lowest and highest possible scores to 0 and 100, respectively. Scores between these values represent the percentage of the total possible score achieved.

• Reverse score item #7 (I feel alone in my life) prior to calculating a total. The instrument scoring is arranged so that a higher score = higher quality of life.

• Then, calculate the mean of the 15 transformed items to form the total score.

At least 12 of the 15 items must have responses in order to compute a total score. Otherwise, set the total score to a missing value.