A study performed in the US in 2009 investigated the degree of influence of different information sources on parental confidence in the safety of the flu vaccine. Over 1500 parents of children aged 17 years or younger participated in the study by answering an internet questionnaire. 76% of the parents answered that they rely strongly on information supplied by their pediatrician, while 26% trusted 'a lot' other healthcare providers. 24% answered that they have a certain degree of faith in comments from public figures relating to the safety of the vaccine. 16% answered that they have no faith at all in the information supplied to them by the government and its representatives. 67% of mothers answered that they have a certain degree of faith in reports from other mothers who claimed that their children were damaged by the vaccine. Women were more likely to trust non-professional sources about the vaccine safety. The authors recommended that doctors should be involved in decision-making and public projects addressing the importance of vaccinating children. In addition, it was suggested that public institutions should use different strategies e.g. social media to distribute information to the public on the importance of vaccination.