Additional file 1: NoD command line manual. The additional file describes the usage of the NoD batch predictor command line utility. Avian Influenza Risk Perception and Preventive Behavior among Traditional Market Workers and Shoppers in Taiwan: Practical Implications for Prevention BACKGROUND: Avian influenza (AI) can be highly pathogenic and fatal. Preventive behavior such as handwashing and wearing face masks has been recommended. However, little is known about what psychosocial factors might influence people's decision to adopt such preventive behavior. This study aims to explore risk perception and other factors associated with handwashing and wearing face masks to prevent AI. METHODOLOGY/PRINCIPAL FINDINGS: An interviewer-administered survey was conducted among 352 traditional market workers and shoppers in Taiwan between December 2009 and January 2010. Factors associated with the recommended AI preventive behavior (i.e., when in a traditional market, wearing a face mask and also washing hands after any contact with poultry) included: having correct knowledge about the fatality rate of AI (adjusted odds ratio [AOR] = 4.18), knowing of severe cases of AI (AOR = 2.13), being informed of local AI outbreaks (AOR = 2.24), living in northeastern Taiwan (AOR = 6.01), having a senior high-school education (AOR = 3.33), and having a university or higher education (AOR = 6.86). Gender interactive effect was also found among participants with a senior high-school education, with males being less likely to engage in the recommended AI preventive behavior than their female counterparts (AOR = 0.34). CONCLUSIONS/SIGNIFICANCE: Specific information concerning AI risk perception was associated with the recommended AI preventive behavior. In particular, having correct knowledge about the fatality rate of AI and being informed of severe cases and local outbreaks of AI were linked to increased AI preventive behavior. These findings underscore the importance of transparency in dealing with epidemic information. These results also have practical implications for prevention and policy-making to more effectively promote the recommended AI preventive behavior in the public. A total of 520 cases of avian influenza (AI) had been reported around the world, resulting in 307 deaths, with a case fatality rate of 59.0% [1] . The AI virus has been found in domestic poultry (e.g., chickens, ducks, geese), wild birds [2] , waterfowl and shorebirds [3] . An extensive review indicated that the AI virus could be transmitted through direct contact with infected poultry, including holding diseased or dead poultry, slaughtering, defeathering, or preparing sick poultry for cooking [4] .