Non-Verbal Communication

I have just read a very interesting article about Non-verbal communication.

It claims that 25% of individuals on the spectrum cannot functionally communicate with others using their voice. This seems very high to me and would present some very worrying barriers in a workplace setting!

It goes in to say that one of the first challenges is defining exactly what is menat by "non-verbal". Some individuals apparently have spoken words, but do not use them functionally; others may have little spoken language but are able to use it to communicate their needs.

I had a dispute with a member of my staff many years ago, In her formal response she claimed that I had a "communication problem". One of the things she cited was that I didn't make eye contact during meetings (fair enough) but I didn't think that my verbal communication - words - were insufficient/ineffective.

Can anyone throw any insight into the above?