APD can also be confused with Specific language impairment (SLI).
SLI is more specifically a problem associated with the linking of words, both written and spoken, to semantics (meaning) and someone can have both APD and SLI. Unlike those with SLI, those with APD can usually get the meaning of language from written words where those with SLI show problems with both heard and read words, demonstrating that the basic issue is not an auditory one.
Those with APD have auditory difficulty distinguishing sounds including speech from extraneous sounds, e.g. fans or other chatter. APD is purely about processing what you hear both verbal and non-verbal. For those who have APD, difficulty processing verbal language is only one of many symptoms.