I'm going to go back on something I just said about using orthographic views. If you have good reference photos that you're going to use as comparison overlays for measuring, it's probably better to try and match the camera views of those pictures. I'm most likely getting anal here but it will make a difference.
If you're going from other sources like  anatomical measurement charts, the orthographic method is the way I'd go.

If I had the skills to model I'm afraid I would be totally anal about all this and most likely work to RW units inside the 3d app and possibly even make measuring objects (although you probably have accessible ruler tools - 3dsMax used to last time I used it back at version 5).

 

PoserPro2014(Sr4), Win7 x64, display units set to inches.

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