Yeah. Deckard's boss accuses him of being an android. The bounty hunter of the station uses the testing equipment to test the whole department and Deckard and Resch find out the whole department is staffed by them including Deckard's boss who accused him of being an android.
When Deckard and Resch take the test it is determined Deckard is human but with more empathy for androids and Resch is also human but with a very low capacity to empathize and basically a sociopath.
I too read the book.... I am, or was, a Sci-fi fan... i just have a rotten memory and forget the ending and most of the plot to every story i read :P But i did seem to have the impression that there was no suggestion that Deckard was a replicant.. To be honest, I never felt that from the film either... I think it was something some people read into it that wasn't necessarily there.