Sentence:  Of the 68 women, 26 reported that they had worked on the streets and as an <WSD>escort</WSD> over the course of their career as a prostitute, 18 exclusively as a street prostitute, and 8 as an <WSD>escort</WSD> only (i.e., working for an escort service). 
Meaning of the word marked with <WSD> tags:  A sex worker who does not operate in a brothel, but with whom clients make appointments; a call girl or male equivalent.