An R Package to Estimate Sample Sizes for Multi-Reader Multi-Case (MRMC) Studies
MRMCsamplesize is an R package with a function to estimate number of cases and readers required for a planned MRMC study. It does so based on the Obuchowski-Rockette (OR) model for statistical analysis of MRMC data. The package is meant only for sample size estimation and it cannot be used for statistical analysis of MRMC data.
Detailed documentation now available as a preprint in medRxiv
NOTE: The methodology does not incorporate the changes proposed by Hillis et. al. by using a modified denominator degrees of freedom. The current methodology uses the denominator degrees of freedom proposed by Obuchowski and Rockette in their original publication. This is known to be very conservative (Hillis 2007). This means that the the number of required cases for a given number of readers outputted by the program can be considered as very conservative and it will typically have considerably more than >P% power where P is the required power you would have assigned as a value to the corresponding argument in the R function. Option to incorporate modified degrees of freedom by Hillis is in development.
How to install the package
#You can install it directly from CRAN as usual
install.packages("MRMCsamplesize")
#You can also install using devtools the version in Github (this version is the same as in CRAN)
library("devtools")
install_github("technOslerphile/MRMCsamplesize")
Usage example
library("MRMCsamplesize")
result1 <- sampleSize_MRMC(endpoint = 'auc',J = 10,delta = 0.10,theta = 0.75,
rangeb = 0.1, rangew = 0.05, R = 1, r1 = 0.47,corr = FALSE)
result2 <- sampleSize_MRMC(endpoint = 'auc',J = 20,delta = 0.05,theta = 0.75,
rangeb = 0.2, rangew = 0.05, R = 1, r1 = 0.47,corr = TRUE, ICC = 0.5, s = 1.25)
result3 <- sampleSize_MRMC(endpoint = 'se',J = 15, delta = 0.05, theta = 0.75,
rangeb = 0.2, rangew = 0.025, R = 1, r1 = 0.5, corr = TRUE, ICC = 0.5, s = 1.25)
I gladly welcome all suggestions for improvements and collaborations
Please report any bugs or issues here
Please cite this package if you use it for your research
Dennis Robert, Saigopal Sathyamurthy S, Preetham Putha. MRMCsamplesize: An R Package for Estimating Sample Sizes for Multi-Reader Multi-Case Studies. medRxiv. Published online 2023. doi:10.1101/2023.09.25.23296069