Background: The relationship between the Mental Illness Needs Index (MINI) and the common mental disorders is not known.
Aims: To investigate associations between the small-area MINI score and common mental disorder at individual level.
Method: Mental health status was measured using the Mental Health Inventory of the Short Form 36 instrument (SF-36). Data from the Caerphilly Health and Social Needs population survey were analysed in multilevel models of 10 653 individuals aged 18-74 years nested within the 2001 UK census geographies of 110 lower super output areas and 33 wards.
Results: The MINI score was significantly associated with common mental disorder after adjusting for individual risk factors. This association was stronger at the smaller spatial scale of the lower super output area and for individuals who were permanently sick or disabled.
Conclusions: The MINI is potentially useful for small-area needs assessment and service planning for common mental disorder in community settings.