The 39-Item Parkinson's Disease Questionnaire (PDQ-39): is it a unidimensional construct?

Peter Hagell, Maria H. Nilsson

Forskningsoutput: TidskriftsbidragArtikelPeer review

38 Citeringar (Scopus)

Sammanfattning

The 39-item Parkinson's Disease Questionnaire, and particularly its summary index (PDQ-39SI) is a widely used patient-reported clinical trial endpoint. A basic assumption when summing items into a total score is that they represent a common variable. We therefore assessed the unidimensionality of the PDQ-39SI using Rasch and confirmatory factor analysis. Both analyses showed model misfit. Adjustment for differential item functioning and disordered response category thresholds did not improve model fit, and residual analyses showed deviation from unidimensionality. These data indicate multidimensionality and challenge the interpretation and validity of PDQ-39SI scores. Clinicians and investigators should use and interpret the PDQ-39SI with caution.

OriginalspråkEngelska
Sidor (från-till)205-214
Antal sidor9
TidskriftTherapeutic Advances in Neurological Disorders
Volym2
Utgåva4
DOI
StatusPublicerad - 2009
Externt publiceradJa

Nationell ämneskategori

  • Neurologi (30207)

Fingeravtryck

Fördjupa i forskningsämnen för ”The 39-Item Parkinson's Disease Questionnaire (PDQ-39): is it a unidimensional construct?”. Tillsammans bildar de ett unikt fingeravtryck.

Citera det här