Computer programs for the concordance correlation coefficient

The CCC macro is presented for computation of the concordance correlation coefficient (CCC), a common measure of reproducibility. The macro has been produced in both SAS and R, and a detailed presentation of the macro input and output for the SAS program is included. The macro provides estimation of three versions of the CCC, as presented by Lin [L.I.-K. Lin, A concordance correlation coefficient to evaluate reproducibility, Biometrics 45 (1989) 255-268], Barnhart et al. [H.X. Barnhart, J.L. Haber, J.L. Song, Overall concordance correlation coefficient for evaluating agreement among multiple observers, Biometrics 58 (2002) 1020-1027], and Williamson et al. [J.M. Williamson, S.B. Crawford, H.M. Lin, Resampling dependent concordance correlation coefficients, J. Biopharm. Stat. 17 (2007) 685-696]. It also provides bootstrap confidence intervals for the CCC, as well as for the difference in CCCs for both independent and dependent samples. The macro is designed for balanced data only. Detailed explanation of the involved computations and macro variable definitions are provided in the text. Two biomedical examples are included to illustrate that the macro can be easily implemented.

[1]  C. Nickerson.  A note on a concordance correlation coefficient to evaluate reproducibility , 1997 .

[2]  N. Cox,et al.  A Note on the Concordance Correlation Coefficient , 2002 .

[3]  S. T. Buckland,et al.  An Introduction to the Bootstrap. , 1994 .

[4]  D. Koh,et al.  Statistical evaluation of agreement between two methods for measuring a quantitative variable. , 1989, Computers in biology and medicine.

[5]  Anthony C. Davison,et al.  Bootstrap Methods and Their Application , 1998 .

[6]  L. Lin,et al.  A concordance correlation coefficient to evaluate reproducibility. , 1989, Biometrics.

[7]  L. Lin.  Assay Validation Using the Concordance Correlation Coefficient , 1992 .

[8]  Hung-Mo Lin,et al.  Resampling Dependent Concordance Correlation Coefficients , 2007, Journal of biopharmaceutical statistics.

[9]  Lluís Jover,et al.  Estimating the Generalized Concordance Correlation Coefficient through Variance Components , 2003, Biometrics.

[10]  V M Chinchilli,et al.  A generalized concordance correlation coefficient for continuous and categorical data , 2001, Statistics in medicine.

[11]  Huiman X Barnhart,et al.  Overall Concordance Correlation Coefficient for Evaluating Agreement Among Multiple Observers , 2002, Biometrics.

[12]  H Quan,et al.  Assessing reproducibility by the within-subject coefficient of variation with random effects models. , 1996, Biometrics.

[13]  H. Barnhart,et al.  Modeling Concordance Correlation via GEE to Evaluate Reproducibility , 2001, Biometrics.

[14]  H. Barnhart,et al.  An Overview on Assessing Agreement with Continuous Measurements , 2007, Journal of biopharmaceutical statistics.