Intensive Outpatient Treatment (also known as IOP for Intensive Outpatient Program) is a primary treatment program recommended in some circumstances by a clinical and medical assessment. IOP may be recommended for those who do not need medically-supervised detox.
The genitive is the case (or function) of an inflected form of a noun or pronoun showing ownership, measurement, association, or source. Adjective: genitival. The suffix -'s on nouns is a marker of genitive case in English. Genitive case can also be indicated by an of phrase after a noun.
The genitive case is also used in sentences expressing negation, even when no possessive relationship is involved. The ending of the subject noun changes just as it does in possessive sentences. The genitive, in this sense, can only be used to negate nominative, accusative and genitive sentences, and not other cases.