{Reference Type}: Journal Article
{Title}: Physical performance tasks were linked to the PROMIS physical function metric in patients undergoing hemodialysis.
{Author}: Liegl G;Fischer FH;Woodward M;Török M;Strippoli GFM;Hegbrant J;Davenport A;Cromm K;Canaud B;Bots ML;Blankestijn PJ;Barth C;Fischer KI;Rose M;
{Journal}: J Clin Epidemiol
{Volume}: 159
{Issue}: 0
{Year}: 2023 07 25
{Factor}: 7.407
{DOI}: 10.1016/j.jclinepi.2023.04.007
{Abstract}: To investigate whether a multi-item performance outcome measure, the physical performance test (PPT), can be calibrated to a common scale with patient-reported outcome measures, using the Patient-Reported Outcomes Measurement Information System (PROMIS) physical function (PF) metric.<BR>We analyzed baseline data (N = 1,113) from the CONVINCE study, an international trial in end-stage kidney disease patients comparing high-dose hemodiafiltration with high-flux hemodialysis. Assumptions of item response theory (IRT) modelling were investigated for the combined set of the nine-item PPT and a four-item PROMIS PF short form (PROMIS-PF4a). We applied unidimensional IRT linking for calibrating the PPT to the PROMIS PF metric.<BR>Although some evidence for multidimensionality was found, classical test statistics (Cronbach's Alpha = 0.93), Mokken (Loevinger's H = 0.50), and bifactor analysis (explained common variance = 0.65) indicated that PPT and PROMIS-PF4a items can be used to assess a common PF construct. On the group level, the agreement between PROMIS-PF4a and linked PPT scores was stable across several subsamples. On the individual level, scores differed considerably.<BR>We found preliminary evidence that the PPT can be linked to the PROMIS PF metric in hemodialysis patients, enabling group comparisons across patient-reported outcome and performance outcome measures. Alternative linking methods should be applied in future studies using a more comprehensive PROMIS PF item set.