We provide functions for visualisation of, e.g., Rasch item fit and DIF using a Conditional Item Characteristic Curve (CICC).
This is an R package. R is required, RStudio is recommended.
The package is available on GitHub. To install the package, start by installing the devtools package. The best way to do this is from CRAN, by typing:
install.packages("devtools")
Install the RASCHplot package from GitHub using the following code.
devtools::install_github("ERRTG/RASCHplot", build_vignettes = TRUE)
After installing the package has to be attached as usual:
library(RASCHplot)
And you are ready to go!
Christensen, Karl & Thorborg, Kristian & Holmich, Per & Clausen, Mikkel. (2018). "Rasch validation of the Danish version of the shoulder pain and disability index (SPADI) in patients with rotator cuff-related disorders." Quality of Life Research 28. https://doi.org/10.1007/s11136-018-2052-8.
Roach, K. E., Budiman-Mak, E., Songsiridej, N., & Lertratanakul, Y. (1991). "Development of a shoulder pain and disability index." Arthritis Care and Research: The Official Journal of the Arthritis Health Professions Association 4 (4), 143--149. https://doi.org/10.1002/art.1790040403