SimpleITK, numpy, scipy, and voxel ordering

Following up on Images in physical space in Python

Was it decided how x,y,z in SimpleITK, is represented? I can’t find a complete description of the voxel dimension ordering in Fundamental Concepts — SimpleITK 2.0rc2 documentation

This question also extends to vectors and time series, is there a consistent physical ordering? I would guess its LPS based on other things I’ve seen in ITK, but I can’t find a place its confirmed to be this way.