Murphy S M, Edwards R T, Williams N et al. An evaluation of the effectiveness and cost effectiveness of the National Exercise Referral Scheme in Wales, UK: a randomised controlled trial of a public health policy initiative. J Epidemiol Community Health 2012;66:8 745–753. There is an error in the second sentence of the Results section in the abstract. It should read: For those referred for mental health reason alone, or in combination with CHD, there were significantly lower levels of anxiety (−1.56, 95% CI −2.75 to −0.38) and depression (−1.39, 95% CI −2.60 to −0.18), but no effect on physical activity.