The topic of this publication is the design of interval observers for LPV systems under consideration of parameter, input and output uncertainties that are described by bounded intervals. In the course of the design, also time-varying bounds of the parameter intervals are considered representing the case when parameters are measured with an unknown but bounded measurement error. In this case, an existing approach is extended to handle these parameter uncertainties. The effectiveness of the approach is demonstrated by two numerical examples. (C) 2018 Elsevier Ltd. All rights reserved.