Testing Pneumonia Vaccines in the Elderly: Determining a Case Definition for Pneumococcal Pneumonia in the Absence of a Gold Standard. - Jokinen J; Snellman M; Palmu AA; Saukkoriipi A; Verlant V; Pascal T; Devaster JM; Hausdorff WP; Kilpi TM (American journal of epidemiology, 2018)