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tcrat Readme

The R package "thyroid" provides software for calculating the absolute risk of second primary thyroid cancer (SPTC) following a childhood cancer based on a prediction model developed and validated by researchers at the National Cancer Institute (NCI).

Before using the tool, please note the following:

  • This program may be useful for research purposes
  • The tool is designed for predicting the SPTC risk in individuals who were diagnosed with a childhood cancer (a non-thyroid malignancy before age 21 years) five or more years before the prediction starting age and have not already been diagnosed with another primary cancer.


  1. This package requires R version 2.10 or higher and the packages fgui and survival. To download the latest version of R for Linux, MacOS X, or Windows platforms visit: To install packages use install.packages(). To check if a package is available, use library().
  2. After downloading and decompress the files to a directory of your choice. After decompressing, a subdirectory named "thyroid" will be created and will contain subfolders with the compressed R scripts and documentation files.
  3. Begin R and use the following command to load the package from where should be replaced by a string indicating the path where the folder "thyroid" is located:
    > library("thyroid", lib.loc = ).
    For example, if the file was decompressed on a Windows machine to C:\Desktop\R Libraries\, the command would be
    > library("thyroid", lib.loc = "C:/Desktop/R Libraries/")