The questionnaire collected the following data : (1) knowledge about seasonal influenza and vaccination (22 items requiring true, false or unsure responses) included five dimensions to assess general information, severity of influenza, influenza vaccination, high-risk groups and vaccination-recommended groups; (2) risk perception (12 items with a 4-point Likert scale) towards influenza and pandemic with three dimensions (i.e. personal vulnerability to illness, negative consequences of contracting influenza and severity of influenza) ; (3) health locus of control including internal, chance and powerful others dimensions assessed by the Multidimensional Health Locus of Control (MHLC) scales [28] (18 items) ; (4) vaccination behaviours (nine items) including vaccination status (whether respondents had been vaccinated in the previous season), vaccination intent (whether respondents intended to be vaccinated next season) and vaccination history (how many times respondents had been vaccinated in the last 5 years) ; (5) reasons for accepting or refusing vaccination using two open questions; and (6) demographic characteristics (10 items) including gender, age group, highest educational qualification, place of work, clinical speciality, year of qualification as a nurse and whether or not respondents had direct patient contact. The Cronbach's a-coefficients for the three newly developed scales (sections 1, 2, 4) ranged from 0 . 701 to 0 . 763 and principal components analysis produced a good fit and confirmed the internal design of the instrument.