BACKGROUND Physical function (PF) is a core patient-reported outcome domain in clinical trials in rheumatic diseases. Frequently used PF measures have ceiling effects, leading to large sample size requirements and low sensitivity to change. In most of these instruments, the response category that indicates the highest PF level is the statement that one is able to perform a given physical activi...

Patient-reported outcome is an important part of the evaluation of a surgical procedure. Numerous questionnaires for patient's self-assessed activity limitation because of cataract have been published. The technique for constructing and evaluating questionnaires has changed over time. This review evaluates the psychometric properties of patient questionnaires that have been published since 1992...

In the original article, it was written that “Then MLE scoring and DIF analysis with RDIF statistics were performed using est_score rdif functions, respectively, in R (R Core Team, 2019) package irtplay (p.90).” However, has been removed from CRAN repository due to intellectual property (IP) violation issues. Instead, a new called irtQ (Lim & Wells, 2023) released as successor irtplay. All IP i...

BACKGROUND Instrumental activities of daily living (IADLs) exhibit strong predictive power for the presence of dementia and mild cognitive impairment. However, IADLs are often less effective in younger cohorts or in healthy community-dwelling samples, presenting with large ceiling effects. This study aimed to construct an IADL scale with an extended range. An effort was made to incorporate leis...

Despite theoretical differences between item response theory (IRT) and classical test theory (CTT), there is a lack of empirical knowledge about how, and to what extent, the IRTand CTT-based item and person statistics behave differently. This study empirically examined the behaviors of the item and person statistics derived from these two measurement frameworks. The study focused on two issues:...

Skillful performance in a human language often involves a composite of elementary skills, such that language skills, cognitive skills, and social skills can be conflated in the judgement of a human listener. A new, computer-based method (PhonePass testing) provides an estimate of spoken language skills, relatively independent of the speaker's other social and cognitive skills. The PhonePass sys...