Convergent validation of EQ-5D-5L in patients with Parkinson's disease

doi:10.1016/j.jns.2015.08.010

Journal of the Neurological Sciences

Volume 358, Issues 1–2, 15 November 2015, Pages 53-57

https://doi.org/10.1016/j.jns.2015.08.010 Get rights and content

Highlights

•
Convergent validity of EQ-5D-5L in Mexican subjects with PD was evaluated.
•
EQ-5D-5L was found to be internally consistent (Cronbach's α = 0.828).
•
Correlation between EQ-5D-5L index and PDQ-8 index was strong (rs = 0.75).
•
EQ-5D-5L was valid among clinically and demographically heterogeneous patients.
•
EQ-5D-5L showed adequate known groups validity.

Abstract

Introduction

The European Quality of Life Questionnaire 5 level version (EQ-5D-5L) is a recently updated instrument to assess Health-Related Quality of Life (HRQoL) that has not been validated extensively. The main objective of this study was to evaluate the internal consistency and convergent validation of the EQ-5D-5L in a large sample of subjects with Parkinson's disease (PD).

Methods

A cross-sectional study was carried out. Consecutive Mexican subjects with PD were included. HRQoL was assessed using the EQ-5D-5L and the PDQ-8. Validity of the EQ-5D-5L was assessed determining its association with clinical ratings of disease severity, as well as correlation with PDQ-8. Additionally, performance was evaluated along predefined groups based on clinical and demographic data of known determinants of quality of life.

Results

A total of 585 patients were included for this study. A strong correlation was found between EQ-5D-5L index and PDQ-8 index (Spearman's correlation coefficient = − 0.75; p < 0.001). Correlation between EQ-5D-5L index and PDQ-8 index remained strong (− 0.60 to − 0.78; p values < 0.001) through all predefined groups. EQ-5D-5L scored higher in those patients with dyskinesia, wearing off, freezing, postural instability, cognitive impairment or depressive mood (p values < 0.001).

Conclusion

The EQ-5D-5L is a valid instrument for evaluating HRQoL in PD, performing adequately irrespective of heterogeneous clinical and demographic characteristics, and showing to be sensitive to features of advanced disease and treatment complications.

Introduction

Parkinson's disease (PD) is a progressive neurodegenerative disease characterized by both motor and non-motor features [1]. Currently, management of subjects with PD is focused in symptomatic control and improvement of their quality of life. The impact of different factors on quality of life has recently become a major topic in PD research. These factors include motor symptoms such as motor fluctuations, postural instability and difficulty in activities of daily living; as well as non-motor symptoms like depression and cognitive decline [2], [3]. Recognizing health-related quality of life (HRQoL) as a clinical outcome implies the need of a valid and reliable instrument to assess HRQoL. The International Parkinson and Movement Disorders Society has published recommendations for the measurement of HRQoL in patients with PD distinguishing between “recommended”, “suggested” and “listed” scales [4]. Although these scales are useful for assessing HRQoL in subjects with PD, not all of them are suitable for cost-utility analysis (CUA) of healthcare interventions. An exception to this is the non-specific European Quality of Life Questionnaire 3 level version (EQ-5D-3L), designed to measure five domains into three answering levels [5]. The EQ-5D-3L has been validated in patients with PD [6], [7], [8], and is widely used in CUA studies [9], [10], [11]. Recently, this instrument has been updated to a 5-level version (EQ-5D-5L), with the intention of decreasing the ceiling effect reported for the original version [12]. Since this instrument is relatively new few studies have addressed its validity in specific diseases.

To the best of our knowledge only one study assessing the validation of EQ-5D-5L on Spanish patients with PD has been published [13]. Validation of clinimetric instruments are essential to allow data pooling, as well as international and cross-cultural comparisons. In addition, HRQoL in subjects with Parkinson's disease is affected by several factors related to the disease progression and treatment that should be taken into account when using clinical scales and questionnaires.

The objective of this study is to evaluate the internal consistency and convergent validation of the EQ-5D-5L compared to the Parkinson's Disease Questionnaire Short Form (PDQ-8), as well as the effect of known determinants of HRQoL, in a large sample of Mexican subjects with PD.

Section snippets

Procedure

A cross-sectional study was conducted including consecutive subjects attending the movement disorders outpatient clinic at five different centers in Mexico (Mexico City, Zacatecas, Merida, Monterrey and Guadalajara), with diagnosis with PD as determined by internationally accepted criteria [14]. Consecutive sampling refers to the fact that select every subject that met the inclusion criteria was selected to participate. Subjects with psychosis (based on Movement Disorders Society Unified

Results

A total of 585 patients (54.4% male and 45.5% female) were included. The mean age was 62.9 ± 12.3 years and the mean disease duration was 7.6 ± 6.1 years. All patients had antiparkinsonian treatment (75.7% with levodopa and 60.3% with a dopamine agonist). Mean MDS-UPDRS part III score was 30.5 ± 18.5. The HY staging was distributed as follows: 59.2% mild disease (stages I–II), 30.6% moderate disease (stage III) and 10.2% severe disease (stages IV and V). Mean EQ-5D-5L_index and EQ-VAS score was 0.71 ± 0.2

Discussion

A recent “paradigm shift” in the management of patients with PD has dominated scientific literature in the past 10 years. Previously, treatment was mainly focused on documenting and optimizing motor functions. Now, there is increasing awareness on non-motor features, and the relevance of activities of daily life and the psychological well-being of the patient. Nowadays, measurement of HRQoL is considered as an important clinical outcome. Additionally, instruments such as EQ-5D-5L are

Conclusions

The EQ-5D-5L showed to be a valid instrument for evaluating HRQoL in Mexican patients with PD. In our study this generic scale performed adequately irrespective of heterogeneous clinical and demographic characteristics of patients with PD, showing to be sensitive to features of advanced disease and treatment complications.

Conflict of interest

The authors declare no conflict of interest related to the research covered in this article.

Funding sources

The study required no funding.

References (27)

B. van Hout et al.
Interim scoring for the EQ-5D-5L: mapping the EQ-5D-5L to EQ-5D-3L value sets
Value Health
(2012)
L.C. Tan et al.
Validity and reliability of the PDQ-39 and the PDQ-8 in English-speaking Parkinson's disease patients in Singapore
Parkinsonism Relat. Disord.
(2004)
J. Jankovic
Parkinson's disease: clinical features and diagnosis
J. Neurol. Neurosurg. Psychiatry
(2008)
A. Schrag et al.
What contributes to quality of life in patients with Parkinson's disease?
J. Neurol. Neurosurg. Psychiatry
(2000)
S. Rahman et al.
Quality of life in Parkinson's disease: the relative importance of the symptoms
Mov. Disord.
(2008)
P. Martinez‐Martin et al.
Health‐related quality‐of‐life scales in Parkinson's disease: critique and recommendations
Mov. Disord.
(2011)
R. Rabin et al.
EQ-5D: a measure of health status from the EuroQol Group
Ann. Med.
(2001)
A. Schrag et al.
The EQ-5D—a generic quality of life measure—is a useful instrument to measure quality of life in patients with Parkinson's disease
J. Neurol. Neurosurg.
(2000)
N. Luo et al.
Is EQ-5D a valid quality of life instrument in patients with Parkinson's disease? A study in Singapore
Ann. Acad. Med. Singap.
(2009)
N. Luo et al.
Responsiveness of the EQ-5D and 8-item Parkinson's Disease Questionnaire (PDQ-8) in a 4-year follow-up study
Qual. Life Res.
(2010)

J. Brazier et al.

A review of the use of health status measures in economic evaluation

J. Health Serv. Res. Policy

(1999)

P. Räsänen et al.

Use of quality-adjusted life years for the estimation of effectiveness of health care: a systematic literature review

Int. J. Technol. Assess.

(2006)

C.H. Dowding et al.

A review of the health-related quality of life and economic impact of Parkinson's disease

Drug & Aging

(2006)

Cited by (22)

Heterogeneous pain trajectories in persons with Parkinson's disease
2022, Parkinsonism and Related Disorders
Citation Excerpt :
One such generic tool is the EuroQol 5 dimensions with five response levels (EQ-5D-5L), which measures mobility, self-care, daily activities, anxiety and depression, and pain and discomfort [17]. EQ-5D-5L is a valid and less time-consuming instrument for evaluating HRQoL in PWP [18]. The objective of the current study is to describe longitudinal self-reported pain trajectories in PWP, specifically health-related pain and discomfort captured by EQ-5D-5L.
Pain is a common and complex symptom in Parkinson's disease. The underlying mechanisms and longitudinal patterns are not well understood, which impedes therapeutic decision making. The objectives of this study were to characterize longitudinal pain trajectories, identify clusters (subgroups) with similar patterns, and examine associations with sociodemographic and clinical characteristics.
Latent class growth analysis was applied to 16,863 people with Parkinson's disease stratified by early (N = 8612; <3 years), mid (N = 6181; 3–10 years) and later (N = 2070; >10 years) disease duration over ∼4.5 years (2017–2021) using the Fox Insight Data Exploration Network, to discern clusters of individuals with similar longitudinal patterns of self-reported pain. Associations were evaluated between cluster membership and sociodemographic and clinical factors.
Across the disease duration strata, five clusters were identified. The clusters ranged from none to moderate pain, with a small cluster of subjects with severe pain. The percentage of subjects with moderate (early = 17.3%, mid = 24.2%, later = 34.4%) and severe (early = 2.3%, mid = 4.4%, later = 6.5%) pain at baseline increased across disease duration groups. The trajectories tended to be variable or slightly worsening in the early duration group, more stable in the mid duration group, and improving in the later duration group. Across strata, the clusters with moderate to severe pain were associated with more severe impairment, depression, anxiety and arthritis, higher body mass index, lower income, and lower education.
This latent class growth analysis, applied to people with Parkinson's disease, provides a template for using self-reported outcomes to improve our understanding of pain trajectories.
Test-Retest Reliability of EQ-5D-5L Valuation Techniques: The Composite Time Trade-Off and Discrete Choice Experiments
2018, Value in Health
Citation Excerpt :
In this protocol, the composite TTO (C-TTO) and DCE were the chosen elicitation techniques [4]. Several studies [5–11] concluded that the clinical administration of the descriptive part of the EQ-5D-5L was valid and reliable. Three studies [12–14] evaluated the reliability of the valuation techniques used to obtain value sets.
To explore the test-retest reliability of the composite time trade-off (C-TTO) and discrete choice experiment (DCE) used in the Indonesian five-level EuroQol five-dimensional questionnaire (EQ-5D-5L) valuation study.
A representative sample aged 17 years and older was recruited from the Indonesian general population by stratified quota sampling with respect to residence, sex, and age. Trained interviewers conducted computer-assisted face-to-face interviews using the EuroQol valuation technology. Each respondent valued 10 health states using C-TTO and 7 pairs of health states in a DCE exercise. The retest interview was conducted after 2 weeks by the same interviewer. The Wilcoxon matched-pairs signed-rank test, intraclass correlation coefficient, and multilevel regression were applied in comparing the C-TTO test and retest data. For DCE, the analysis of proportions was used.
A total of 226 respondents with characteristics similar to the Indonesian population completed the retest interview. For C-TTO, 82 (95.3%) of 86 health states had no significant mean value differences between test and retest. The mean value of the second test was statistically significantly higher than that of the first test by 0.042. For DCE, 72.5% of responses were identical. DCE retest showed a different pattern concerning the relative importance of the dimensions, whereas the C-TTO remained the same.
C-TTO is stable over time, whereas in DCE the relative values of the dimensions shift. The results support the use of the C-TTO, in particular the Indonesian EQ-5D-5L value set, and suggest a critical examination of the reliability of DCE results over time.
Older adults' quality of life – Exploring the role of the built environment and social cohesion in community-dwelling seniors on low income.
2016, Social Science and Medicine
Citation Excerpt :
The EQ-5D-5L and ICECAP-O were included in this study because previous work has indicated that these measures are complements (rather than substitutes) in regard to providing information about a person's QoL (Davis et al., 2013). The psychometric properties of the EQ-5D-5L are well established across many countries and population groups (Alvarado-Bolanos et al., 2015; Feng et al., 2015; Golicki et al., 2015; Herdman et al., 2011). Also the ICECAP-O has been validated in a number of studies (in the UK (Coast et al., 2008b), Germany (Makai et al., 2014), Australia (Couzner et al., 2013) and the Netherlands (Makai et al., 2013)) and has consistently been found to be a valid instrument to measure capability wellbeing.
The built environment and social cohesion are increasingly recognized as being associated with older adults' quality of life (QoL). However, limited research in this area still exists and the relationship has remained unexplored in the area of Metro Vancouver, Canada. This study examined the association between the built environment and social cohesion with QoL of 160 community-dwelling older adults (aged ≥ 65 years) on low income from Metro Vancouver. Cross-sectional data acquired from the Walk the Talk (WTT) study were used. Health-related QoL (HRQoL) and capability wellbeing were assessed using the EQ-5D-5L and the ICECAP-O, respectively. Measures of the environment comprised the NEWS-A (perceived built environment measure), the Street Smart Walk Score (objective built environment measure), and the SC-5PT (a measure of social cohesion). The primary analysis consists of Tobit regression models to explore the associations between environmental features and HRQoL as well as capability wellbeing. Key findings indicate that after adjusting for covariates, older adults' capability wellbeing was associated with street connectivity and social cohesion, while no statistically significant associations were found between environmental factors and HRQoL. Our results should be considered as hypothesis-generating and need confirmation in a larger longitudinal study.
The PD-Ballet study: study protocol for a randomised controlled single-blind hybrid type 2 clinical trial evaluating the effects of ballet dancing on motor and non-motor symptoms in Parkinson’s disease
2024, BMC Complementary Medicine and Therapies
Monash-Alfred protocol for assessment of atypical parkinsonian syndromes (MAP-APS)
2024, BMJ Neurology Open
A person-centered approach to characterizing longitudinal ambulatory impairment in Parkinson's disease
2024, Research Square

View all citing articles on Scopus

View full text

Convergent validation of EQ-5D-5L in patients with Parkinson's disease

Highlights

Abstract

Introduction

Methods

Results

Conclusion

Introduction

Section snippets

Procedure

Results

Discussion

Conclusions

Conflict of interest

Funding sources

Value Health

Parkinsonism Relat. Disord.

Parkinson's disease: clinical features and diagnosis

J. Neurol. Neurosurg. Psychiatry

What contributes to quality of life in patients with Parkinson's disease?

J. Neurol. Neurosurg. Psychiatry

Quality of life in Parkinson's disease: the relative importance of the symptoms

Mov. Disord.

Health‐related quality‐of‐life scales in Parkinson's disease: critique and recommendations

Mov. Disord.

EQ-5D: a measure of health status from the EuroQol Group

Ann. Med.

The EQ-5D—a generic quality of life measure—is a useful instrument to measure quality of life in patients with Parkinson's disease

J. Neurol. Neurosurg.

Is EQ-5D a valid quality of life instrument in patients with Parkinson's disease? A study in Singapore

Ann. Acad. Med. Singap.

Responsiveness of the EQ-5D and 8-item Parkinson's Disease Questionnaire (PDQ-8) in a 4-year follow-up study

Qual. Life Res.

A review of the use of health status measures in economic evaluation

J. Health Serv. Res. Policy

Use of quality-adjusted life years for the estimation of effectiveness of health care: a systematic literature review

Int. J. Technol. Assess.

A review of the health-related quality of life and economic impact of Parkinson's disease

Drug & Aging