Refractory high entropy alloys (RHEAs) are promising materials for aerospace applications due to their superior properties at ultrahigh temperatures. One of their prominent features is the presence of local lattice distortions (LLDs), which have been suggested to have a critical effect on dislocation movement, strength and thermal stability of HEAs. Controlling the LLDs in RHEAs therefore appears to be a promising route to optimize both thermal stability and mechanical properties. However, there still lacks substantial analysis in quantifying LLDs, as reliable and consistent data is missing due to the difficulty in their accurate determination. Total scattering and the real-space atomic pair distribution function (PDF) have been shown to provide unique insights into LLDs, but the analysis assumes of an idealized homogeneous microstructure. However, heterogeneity is ubiquitous within as-cast RHEAs under practical circumstances. It is therefore desirable to validate the effect of segregation on PDFs, and accordingly to improve the reliability of evaluating LLDs via this technique. Here, the effect of chemical segregation on PDFs of a group of RHEAs was investigated. First we examine the signatures of LLD in RHEAs in diffraction data available in literature using separation of static and dynamic contributions to the measured off-site displacements (Uiso). The analysis suggests that the LLDs in these systems are large compared to those reported for fcc HEAs, and should be readily measurable. Based on comparison with our own experimental data we argue that real-space fitting is preferrable over Rietveld refinement of diffraction data for this type of LLD analysis. We proceed to use simulation of "composite" PDFs representing heterogeneous microstructures constructed through superposition of individual homogeneous components with different lattice parameters and compositions, to quantify the effects of segregation on LLD analysis using small-box modelling.