The COSMIN checklist for assessing the methodological quality of studies on measurement properties of health status measurement instruments: an international Delphi study.
BACKGROUND
Aim of the COSMIN study (COnsensus-based Standards for the selection of health status Measurement INstruments) was to develop a consensus-based checklist to evaluate the methodological quality of studies on measurement properties. We present the COSMIN checklist and the agreement of the panel on the items of the checklist.


METHODS
A four-round Delphi study was performed with international experts (psychologists, epidemiologists, statisticians and clinicians). Of the 91 invited experts, 57 agreed to participate (63%). Panel members were asked to rate their (dis)agreement with each proposal on a five-point scale. Consensus was considered to be reached when at least 67% of the panel members indicated 'agree' or 'strongly agree'.


RESULTS
Consensus was reached on the inclusion of the following measurement properties: internal consistency, reliability, measurement error, content validity (including face validity), construct validity (including structural validity, hypotheses testing and cross-cultural validity), criterion validity, responsiveness, and interpretability. The latter was not considered a measurement property. The panel also reached consensus on how these properties should be assessed.


CONCLUSIONS
The resulting COSMIN checklist could be useful when selecting a measurement instrument, peer-reviewing a manuscript, designing or reporting a study on measurement properties, or for educational purposes.
Mokkink
Lidwine B
LB
Department of Epidemiology and Biostatistics and the EMGO Institute for Health and Care Research, VU University Medical Center, Van der Boechorststraat 7, 1081 BT, Amsterdam, The Netherlands. w.mokkink@vumc.nl
Terwee
Caroline B
CB
Patrick
Donald L
DL
Alonso
Jordi
J
Stratford
Paul W
PW
Knol
Dirk L
DL
Bouter
Lex M
LM
de Vet
Henrica C W
HC
D003697:Delphi Technique; D006305:Health Status Indicators; D006801:Humans; D038622:Internationality; D017063:Outcome Assessment, Health Care / Q000379:methods*; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D012107:Research Design; D018434:Sickness Impact Profile; D013223:Statistics as Topic; D011795:Surveys and Questionnaires