 About 2,000 cases of CAP are expected to occur in the CAPITA cohort in the next two to three years. Assuming a response rate of 30 for the baseline questionnaire, we will have some 600 CAP cases out of the 2,000 expected patients for whom a baseline EQ-5D score is available. These CAP patients will be asked to participate in a prospective cohort study. Within CHO-CAP, these CAP cases will be followed for up to one year after their CAP episode. For each CAP case included in the CAP cohort, two controls from the baseline population are matched and included in a cohort of controls non-CAP elderly with similar baseline health status. Controls will also be followed for up to one year. The matches between CAP cases and controls will be made based on age, sex and EQ-5D baseline score. This implies that controls will only be recruited from the group that responded to the baseline measurement of health status shortly after vaccination. For both cohorts, the CAP patients and the matched controls, additional data on health care and non-health care resource use, on health status, using EQ-5D and SF-36 questionnaires, and on selected health outcomes is collected at four contact at 0, 1, 6 and 12 months moments within a period of 1 year. This will be done using questionnaires, distributed during a home visit and by post. 