[EVAN-65 project: evaluation of the effectiveness of pneumococcus vaccination in the elderly population over 65]

To assess the effectiveness of systematic pneumococcus vaccination (PV) in the over-65s by comparing rates of incidence and severity of the cases of pneumonia caught in the community (PCC), in two cohorts-those vaccinated (VC) and those not (NVC).

Multi-centre study of cohorts.

Primary Health Care.

All those over 65 registered at 8 urban Health Districts and distributed into a VC (with PV) and an NVC.

Active monitoring will be conducted for 3 years, with detection of all the PCC occurring during this period. Data sources will be the specific register of the PV programme and exhaustive review of primary Care and referral hospital clinical records (records of pneumonia cases admitted and records of pneumonia cases detected in Casualty).

Variables considered will be: age, sex, and presence or otherwise of risk factors linked to greater susceptibility to catching pneumonia (diabetes mellitus, low immunity levels, cardiopathy, COPD, tobacco dependency, alcoholism, splenectomy). To measure the effect, we will calculate the annual and overall accumulated (over 3 years) rates of incidence of pneumonia, as well as the relative and attributable risks. As measurements of its severity, we will analyse the mortality index and the "fine" ordinal scale of severity.

The study will give a reply in terms of effectiveness and efficiency of the vaccine and will contribute to a definitive decision on the controversial question of the systematic indication of this vaccine for the over-65 population.