STUDY OBJECTIVE: There is an increasing body of evidence about socioeconomic inequality in preventive use, mostly for cancer screening. But as far as needs of prevention are unequally distributed, even equal use may not be fair. Moreover, prevention might be unequally used in the same way as health care in general. The objective of the paper is to assess inequity in prevention and to compare socioeconomic inequity in preventive medicine with that in health care. DESIGN: A cross sectional Health Interview Survey was carried out in 1997 by face to face interview and self administered questionnaire. Two types of health care utilisation were considered (contacts with GPs and with specialists) and four preventive care mostly delivered in a GP setting (flu vaccination, cholesterol screening) or in a specialty setting (mammography and pap smear). SETTING: Belgium. PARTICIPANTS: A representative sample of 7378 residents aged 25 years and over (participation rate: 61%). Outcome measure: Socioeconomic inequity was measured by the HI(wvp) index, which is the difference between use inequality and needs inequality. Needs was computed as the expected use by the risk factors or target groups. MAIN RESULTS: There was significant inequity for all medical contacts and preventive medicine. Medical contacts showed inequity favouring the rich for specialist visits and inequity favouring the poor for contacts with GPs. Regarding preventive medicine, inequity was high and favoured the rich for mammography and cervical screening; inequity was lower for flu immunisation and cholesterol screening but still favoured the higher socioeconomic groups. In the general practice setting, inequity in prevention was higher than inequity in health care; in the specialty setting, inequity in prevention was not statistically different from inequity in health care, although it was higher than in the general practice setting. CONCLUSIONS: If inequity in preventive medicine is to be lowered, the role of the GP must be fostered and access to specialty ...