Development and validation of QoL5 for clinical databases. A short, global and generic questionnaire based on an integrated theory of the quality of life.
OBJECTIVE
To develop and validate a short, global, and generic quality of life (QoL) questionnaire for clinical databases. The construct validity and item weighting of existing questionnaires are increasingly questioned.


METHODS
Cross-sectional population study.


METHODS
2460 Danes aged 18-88 years, randomly selected through the Danish Central Person Registry.


METHODS
Ten questions covering the spectrum of the integrative theory of QoL together with the Nottingham Health Profile (NHP), Sickness Impact Profile (SIP), and self-estimated QoL questionnaire were sent by mail. A test-retest study of 50 people was conducted after one month.


METHODS
Construct and criterion validity, reliability, and sensitivity.


RESULTS
QoL5 correlations with SIP, NHP, Self-estimated QoL were 0.37, 0.52, and 0.76, respectively, and increased among those who were unwell. Cronbach's alpha was 0.69. All correlations in Siegel's test were over 0.6, and the test-retest correlation was 0.82. Only 12 respondents in each group will be needed to detect a difference of 10% in the QoL score between two groups.


CONCLUSIONS
QoL5 is a valid global and generic QoL measurement. Despite the use of only five questions, internal consistency and sensitivity were acceptable. So a relevant and practical outcome measurement is available for clinical databases.
Department of Vascular Surgery, Rigshospitalet, Copenhagen, Denmark. jslindholt@mail.tele.dk
Jes S
JS
Lindholt
Søren
S
Ventegodt
Eskild W
EW
Henneberg
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D003718:Denmark; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D011788:Quality of Life; D012042:Registries; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires