occreml

Occupancy restricted maximum likelihood (Occ REML)

Occupancy restricted maximum likelihood estimation (Occ REML) is a statistical method to estimate the PET-derived neuroreceptor occupancy of a drug in the absence of a reference region. This method has been found to be substantially more efficient than the standard occupancy plot with ordinary least squares fitting.

Please read "Restricted maximum likelihood estimation of PET neuroreceptor occupancy in the absence of a reference region" by Joaquim Radua, Santiago Bullich, Natalia Lopez and Ana M. Catafau at Medical Physics for more information on the method.

R and Matlab scripts

R: the R script for Occ REML has been included in the occ R package, which also includes the 'reference region' and 'ordinary least squares' methods. Please type the following command in R to install the package:

install.packages("occ")

Alternatively, you can download the source or compiled versions of the package at cran.r-project.org/web/packages/occ.

Matlab: the Matlab script for Occ REML is attached below.

Do not hesitate to use them for your own research and to contact Joaquim Radua should you have any doubt.

Citation

We have invested a lot of time and effort in developing this method, please cite it when using it in your research:

Radua J, Bullich S, Lopez N and Catafau AM. Restrcited maximum likelihood estimation of PET neuroreceptor occupancy in the absence of a reference region. Medical Physics 2011, 38:2558-2562.