According to discussions in This PC Tools Forum Thread, the Spyware Doctor Starter Edition, which is available as a Freeware Download as a part of the Google Pack, has a MUCH Smaller Database. Even during updates it is allowed to download FEWER updates than its subscribed versions.
Most users of the Starter Edition are of the impression that the only limitation in the Starter Edition was that some of the On-Guard facilities were not available. So, what exactly has been left out, other than the obvious ~400K fewer malware signatures in the Starter Editions !? Its a question which may worry users of the Starter Edition.
If this is indeed the case, then PC Tools should have made it clear on its page, here, that apart from the absence of real-time active monitors, the Starter Editions Malware database is also limited, and consequently it does not detect or clean 100% of malware !