The MHQoL is a reliable and valid measure of mental health-related quality of life across countries, with good internal consistency and measurement invariance across Finland, Spain and the UK, and an open-source toolbox was developed to support its consistent implementation.
Key Findings
Results
The MHQoL demonstrated good internal consistency across all three countries, with Cronbach's alpha ranging from 0.741 in Finland to 0.806 in Spain.
Overall Cronbach's alpha was 0.787 across the full sample of 564 employees.
Country-specific alphas: Finland α=0.741 (n=122), Spain α=0.806 (n=114), UK (n=328).
The overall alpha of 0.787 falls within the conventionally accepted range for good internal consistency.
Data were drawn from baseline assessments only; no intervention was delivered for this analysis.
Results
Measurement invariance of the MHQoL was supported across Finland, Spain and the UK, supporting construct validity.
Measurement invariance testing was conducted across three countries with different languages and cultural contexts.
The invariance finding indicates the MHQoL measures the same construct consistently across national contexts.
The sample included workplace settings in small-sized and medium-sized enterprises (SMEs) and public sector organisations.
This cross-national invariance supports use of the MHQoL for cross-country comparisons.
Results
Multilevel regression analyses identified Self-Image, Daily Activities, Mood and Future as the dimensions with the strongest associations with the MHQoL Visual Analogue Scale (VAS).
Multilevel analyses examined associations between MHQoL dimensions and the MHQoL-VAS as the primary outcome measure.
Self-Image, Daily Activities, Mood and Future showed the strongest contributions among all MHQoL dimensions.
The multilevel approach accounted for the nested structure of data across countries.
These findings help identify which dimensions most drive overall mental health quality of life scores.
Results
Convergent validity of the MHQoL was supported by moderate to strong correlations with established mental health and quality of life measures.
Convergent validity was assessed through correlations between MHQoL scores and EQ-5D-5L, PHQ-9, GAD-7, Insomnia Severity Index, PSS-4, Psychosocial Risk Scale and WHO-5.
Correlations with EQ-5D-5L (a general quality of life measure) and related mental health measures were described as moderate to strong.
Seven external validation instruments were used, covering depression, anxiety, insomnia, stress, psychosocial risk and well-being domains.
The breadth of convergent validity evidence supports the MHQoL's coverage of mental health-related quality of life constructs.
Results
An open-source R package and Shiny web application called the 'MHQoL Toolbox' were developed for scoring, transformation and visualisation of MHQoL data.
The toolbox was designed to support consistent, transparent implementation of the MHQoL across research, clinical practice and economic evaluations.
The toolbox includes functionality for scoring, transformation and presentation of MHQoL results.
Developing open-source tools was a stated secondary objective of the study alongside psychometric validation.
The authors state the toolbox 'facilitates use in research, clinical practice and economic evaluations.'
Methods
The study sample consisted of 564 employees from workplace settings across three countries, with notable demographic variation including predominantly female samples.
Total sample: 564 employees — 122 from Finland, 114 from Spain and 328 from the UK.
Participants were mostly white-collar workers in SMEs or public organisations, mainly in public administration, manufacturing, health/life sciences or higher education.
Women were the majority, ranging from 56% to 91% across countries.
Mean age ranged from 43 to 48 years across countries.
Data were drawn from baseline assessments of the EMPOWER multicentre international randomised controlled trial (NCT04907604).
What This Means
This research suggests that the Mental Health Quality of Life questionnaire (MHQoL) is a reliable and valid tool for measuring mental health-related quality of life across different countries. The study analyzed data from 564 workers in Finland, Spain and the UK and found that the questionnaire performed consistently across all three countries — meaning it measures the same underlying concept regardless of national or cultural context. The questionnaire's internal consistency was good, and its scores correlated meaningfully with other established measures of depression, anxiety, stress, insomnia and general quality of life, confirming it captures what it is designed to measure.
The study also identified which parts of the questionnaire matter most for an overall sense of mental health quality of life: people's feelings about their self-image, their ability to carry out daily activities, their mood and their outlook on the future were the strongest contributors to overall scores. This information could help clinicians and researchers understand which areas of mental health are most closely tied to a person's overall quality of life.
To make the questionnaire easier to use, the researchers also built a free, open-source software toolbox (an R package and a web application) that allows anyone to score, process and visualize MHQoL data. This research suggests the MHQoL could be practically useful in a wide range of settings — from clinical care and workplace mental health programs to health economic evaluations — particularly when comparisons across countries are needed.
Peeters S, Thielen F, De Mul M, Sinokki M, Olaya B, Van Der Feltz-Cornelis C, et al.. (2026). Cross-national validation of the MHQoL: psychometric evaluation and open-source tools for assessing mental health quality of life.. BMJ open. https://doi.org/10.1136/bmjopen-2025-108598