Data were analysed using SPSS version 20. Descriptive statistics were used to summarize and describe the demographic and clinical characteristics of the sample. Independent sample t-test, ANOVA and Pearson product–moment correlation were used to compare scale means and correlations of the SF-12, MOS-SSS and HADS scores. SF-12 mean scores were generated from QualityMetric Health OutcomesTM Scoring Software 4.5 provided by the distributors of the instrument. Stepwise multiple linear regression analysis was used to identify predictors of HRQoL. All the independent variables which demonstrated significant differences or correlations with SF-12 PCS or MCS (i.e. p b .05) were included in the multiple linear regression analysis using the stepwise method to determine predictors of HRQoL.