A two-stage selection process is used to ensure equal representation of males and females. QSS 2009 consisted of a standardized introduction, specific questions incorporated by researchers and the University, and 37 demographic questions. The questions were pilot tested by www.selleckchem.com/products/SB-203580.html trained interviewers in 92 randomly-selected households, with modifications to the questions guided by both responses from the subjects and feedback from the interviewers. Final interviewing

was conducted between July 20, 2009, and August 19, 2009, between the hours from 10:30am to 2:30pm and 4:30pm to 8:30pm on weekdays, and between the hours of 11:00am and 4:00pm on weekends. Two questions related to travel and Pandemic (H1N1) 2009, which was presented as Swine flu in the questionnaire, were incorporated into QSS 2009. The first question asked respondents to rate their level of concern about Pandemic (H1N1) 2009, when traveling, using a 5-point balanced Likert scale; the CP-868596 in vitro second question asked

respondents to use a 4-point Likert scale to rate how likely they would be to cancel commercial air travel, if they themselves had symptoms of a viral respiratory disease. Responses were subsequently dichotomized as “yes” (strongly agree/agree or very likely/likely) and “no” (strongly disagree/disagree or very unlikely/unlikely), and cross-tabulated in a 2 × 2 table. Associations between concern and likelihood of cancelling travel were analyzed using χ2, as were associations between relevant demographic variables and concern about Pandemic (H1N1) 2009 and willingness to cancel travel. Where demographic variables were recorded as ordinal data, analyses utilizing χ2 for linear-by-linear association were conducted to identify any significant trend effects. Subsequently, multivariate logistic regression was conducted to identify covariates and interaction

effects, and to adjust for confounding. Each variable was see more entered into or removed from the logistic regression model using both forward and backward methods to identify significant covariates; the remaining variables were then individually entered into the model to identify potential confounders. The final model included significant covariates, potential confounders, and significant interaction effects. For all analyses, p < 0.05 was used to establish statistical significance; for the multivariate analysis, adjusted odds ratios (AOR) and their 95% confidence intervals (CI) are reported. QSS 2009 had a target sample size of 1,200 subjects, with 800 subjects from Southeast Queensland and 400 from Other Queensland; thus the a priori estimated sampling error at the 95% confidence level was ±2.9% for the entire sample, ±3.6% for the Southeast Queensland sub-sample, and ±5.1% for the Other Queensland sub-sample.