The minimal clinically important difference determined using item response theory models: an attempt to solve the issue of the association with baseline score.
Fiche publication
Date publication
avril 2014
Auteurs
Membres identifiés du Cancéropôle Est :
Pr GUILLEMIN Francis
Tous les auteurs :
Rouquette A, Blanchin M, Sebille V, Guillemin F, Cote SM, Falissard B, Hardouin JB
Lien Pubmed
Résumé
OBJECTIVES: Determining the minimal clinically important difference (MCID) of questionnaires on an interval scale, the trait level (TL) scale, using item response theory (IRT) models could overcome its association with baseline severity. The aim of this study was to compare the sensitivity (Se), specificity (Sp), and predictive values (PVs) of the MCID determined on the score scale (MCID-Sc) or the TL scale (MCID-TL). STUDY DESIGN AND SETTING: The MCID-Sc and MCID-TL of the MOS-SF36 general health subscale were determined for deterioration and improvement on a cohort of 1,170 patients using an anchor-based method and a partial credit model. The Se, Sp, and PV were calculated using the global rating of change (the anchor) as the gold standard test. RESULTS: The MCID-Sc magnitude was smaller for improvement (1.58 points) than for deterioration (-7.91 points). The Se, Sp, and PV were similar for MCID-Sc and MCID-TL in both cases. However, if the MCID was defined on the score scale as a function of a range of baseline scores, its Se, Sp, and PV were consistently higher. CONCLUSION: This study reinforces the recommendations concerning the use of an MCID-Sc defined as a function of a range of baseline scores.
Référence
J Clin Epidemiol. 2014 Apr;67(4):433-40