Random variation and systematic error caused by various preanalytical variables, estimated by linear mixed-effects models
Sylte, M. S., Wentzel-Larsen, T., & Bolann, B. J. (2013). Random variation and systematic error caused by various preanalytical variables, estimated by linear mixed-effects models. Clinica Chimica Acta, 415(16), 196-201. doi:10.1016/j.cca2012.10.045