The model in this paper is motivated by a study of the effectiveness of pulsed electromagnetic field energy on healing of wounds, in which the wound sizes zijr at time t for subject j under treatment i were observed with error. The healed wound size yijt, defined by zij,t-1-zijt, is modeled as the dependent variable in a repeated-measurement model. Two classical measurement error models relating the observed proxy wound size z*ijt and the true wound size zijt are considered: additive and multiplicative measurement error models. In this paper, we propose estimates of variance parameters, including the variance of the measurement error, via the method of moments when the dependent variable yijt is erroneously measured due to the measurement error in zijt. The proposed estimates of variance parameters are shown to be consistent and perform well in the simulation.
- Additive measurement error model
- General linear mixed model
- Multiplicative measurement error model