This paper treats parametric identification of the complex modulus of a viscoelastic material. A theoretical expression for the accuracy of the estimate is derived under the assumption that the measurement noise is white and that the signal-to-noise ratio is large. The expression is validated against both simulated and experimental data. In the case of experimental data it is seen that the theoretical expression severely underestimates the variance of the identified parameters, and it is therefore modified to cover the case of correlated noise with much better agreement as a result. (C) 2011 Elsevier Ltd. All rights reserved.