Complex sentence: Intrinsic factor antibodies are much less sensitive than parietal cell antibodies, however they are much more specific; they are found in approximately half of PA patients, whereas they are very rarely found in other disorders.
Split into simpler sentences: Intrinsic factor antibodies are much less sensitive than parietal cell antibodies, however they are much more specific. They are found in approximately half of PA patients and are very rarely found in other disorders.