Article type
Year
Abstract
Objective: Aim of this study was to compare the validity and pertinence of available questionnaires assessing symptoms of vertigo or dizziness and their impact on quality of life.
Methods: Publications were retrieved through Medline and Embase databases (1991-2000). 24 publications reporting validation of questionnaires or use of these questionnaires in clinical trials were selected. Each publication was reviewed using a methodological checklist from the ANAES (Agence Nationale d'Accréditation et d'Evaluation en Santé) and a quality of life specific checklist (1). A global score ranging from 0 to 100 (best) was given to each questionnaire, reflecting the different levels of validation (content validity, structural validity, discriminant validity, criterion validity, reliability, responsiveness).
Results: Nine questionnaires were arbitrarily classified, according to their content, into 3 groups: essentially symptomatic questionnaires, essentially quality of life or handicap questionnaires and questionnaires assessing both symptoms of vertigo and impact. The tenth questionnaire was specific of Meniere disease (MD-POSI). Global score of validation range from 36 to 77. All questionnaires (except EEV) were self-administered. EEV scoring is based on both evaluation of patients and physicians. Major results indicate that the questionnaire cited as a reference and mostly used, i.e. DHI lacks some part of validity. Noticeably, its structural validity has been found to be quite different in 2 further studies compared to the original validation study. Reproducibility (test-retest) has been flawly assessed for a number of questionnaires, i.e. with a low number of patients and/or with a too short interval. Responsiveness, which is critical for assessing changes with therapy, has rarely been evaluated. However, the European Evaluation of Vertigo has demonstrated a large effect size of its global and subscales scores in a longitudinal study.
Conclusion: Questionnaires reviewed in this study have shown that most of them reflecting handicap or impact on quality of life are not very specific of vertigo or dizziness, or that they have validation flaws. The VHQ appears to have the most pertinent content, but its validation remains to be performed. Mixed questionnaires have the same imperfections, even if the VDI has the best validation score. Among symptomatic questionnaires, the EEV seems to satisfactory evaluate the 5 major vertigo symptoms. Self-assessment of symptoms and impact on quality of life are of greater importance in the evaluation of therapeutic strategies in the context of vertigo and dizziness. This review was not able to specify the definite specific quality of life questionnaire. For most of the questionnaires reviewed, responsiveness is unknown.
DHI Dizziness Handicap Inventory
VADL Vestibular Disorders Activities of Daily Living scale
ABC Activities-specific Balance Confidence scale
VHQ Vertigo Handicap Questionnaire
VDI Vertigo Dizziness Imbalance questionnaire
UCLA-DQ UCLA Dizziness Questionnaire
DFI Dizzy Factor Inventory
VSS Vertigo Symptom Scale
EEV European Evaluation of Vertigo
MD-POSI Meniere's Disease Patient-Oriented Severity Index
(1) Chassany O, Sagnier P, Marquis P, et al. Patient-Reported Outcomes : The Example of Health-Related Quality of Life - A European guidance document for the improved integration of Health-Related Quality of Life assessment in the drug approval process. Drug Information Journal 2002; 36:209-238.
Methods: Publications were retrieved through Medline and Embase databases (1991-2000). 24 publications reporting validation of questionnaires or use of these questionnaires in clinical trials were selected. Each publication was reviewed using a methodological checklist from the ANAES (Agence Nationale d'Accréditation et d'Evaluation en Santé) and a quality of life specific checklist (1). A global score ranging from 0 to 100 (best) was given to each questionnaire, reflecting the different levels of validation (content validity, structural validity, discriminant validity, criterion validity, reliability, responsiveness).
Results: Nine questionnaires were arbitrarily classified, according to their content, into 3 groups: essentially symptomatic questionnaires, essentially quality of life or handicap questionnaires and questionnaires assessing both symptoms of vertigo and impact. The tenth questionnaire was specific of Meniere disease (MD-POSI). Global score of validation range from 36 to 77. All questionnaires (except EEV) were self-administered. EEV scoring is based on both evaluation of patients and physicians. Major results indicate that the questionnaire cited as a reference and mostly used, i.e. DHI lacks some part of validity. Noticeably, its structural validity has been found to be quite different in 2 further studies compared to the original validation study. Reproducibility (test-retest) has been flawly assessed for a number of questionnaires, i.e. with a low number of patients and/or with a too short interval. Responsiveness, which is critical for assessing changes with therapy, has rarely been evaluated. However, the European Evaluation of Vertigo has demonstrated a large effect size of its global and subscales scores in a longitudinal study.
Conclusion: Questionnaires reviewed in this study have shown that most of them reflecting handicap or impact on quality of life are not very specific of vertigo or dizziness, or that they have validation flaws. The VHQ appears to have the most pertinent content, but its validation remains to be performed. Mixed questionnaires have the same imperfections, even if the VDI has the best validation score. Among symptomatic questionnaires, the EEV seems to satisfactory evaluate the 5 major vertigo symptoms. Self-assessment of symptoms and impact on quality of life are of greater importance in the evaluation of therapeutic strategies in the context of vertigo and dizziness. This review was not able to specify the definite specific quality of life questionnaire. For most of the questionnaires reviewed, responsiveness is unknown.
DHI Dizziness Handicap Inventory
VADL Vestibular Disorders Activities of Daily Living scale
ABC Activities-specific Balance Confidence scale
VHQ Vertigo Handicap Questionnaire
VDI Vertigo Dizziness Imbalance questionnaire
UCLA-DQ UCLA Dizziness Questionnaire
DFI Dizzy Factor Inventory
VSS Vertigo Symptom Scale
EEV European Evaluation of Vertigo
MD-POSI Meniere's Disease Patient-Oriented Severity Index
(1) Chassany O, Sagnier P, Marquis P, et al. Patient-Reported Outcomes : The Example of Health-Related Quality of Life - A European guidance document for the improved integration of Health-Related Quality of Life assessment in the drug approval process. Drug Information Journal 2002; 36:209-238.