Using PubMed, we searched the National Library of Medicine database for manuscripts published before October 31, 2008. The reference terms``pneumonia,''``acute respiratory infection,'' and`l ower respiratory tract infection'' were each combined with`C hina'' and``Mainland China.'' Using equivalent terms, we performed additional searches for publications in the Chinese medical literature using the Wanfang (http://www.wanfangdata. com/) and Chongqingvip (www.cqvip.com) databases [10, 11] . In these databases, publications were available since 1982 and 1989, respectively. The English search terms were translated into Chinese (by author X.G.) for use in the Chinese-language searches [º, %'|8SÓ, |8SÓ (P-ý-ý' F)]. In addition, journal articles cited in the identified manuscripts were collected and added to the review.