Editor's response—preventive or preventative?

We are indebted to Dr Joseph for pointing out an error in the departmental title of a council member. This has now been changed. But which is correct—preventive or preventative? The Oxford English Dictionary provides both spellings but states that the former is the preferred formulation. A recent medical usage is cited: ‘Many of the people are illiterate and it takes a lot of patient talking and convincing before they can see the benefits of preventative medicine’. (Oxf. Mission Q. Paper July/Sept. 15, 1976.) The word can also be used as a noun: ‘I shall not trouble Government with suggestions of remedies or preventatives’. (Wellington in Gurw. Desp. (1838) IX. 462.) Perhaps it was the use of the word ‘preventative’ to mean a contraceptive that has resulted in its declining usage in the context of departments of public health medicine.