Response to: 'Diagnostic accuracy of novel ultrasonographic halo score for giant cell arteritis: methodological issues' by Ghajari and Sabour

We thank Ghajari and Sabour for their interest in our work and appreciation of our study.1 We have reported that the extent of vascular inflammation on ultrasound, as quantified by the halo score, is associated with ocular ischaemia in patients with giant cell arteritis (GCA).2 Furthermore, we investigated the diagnostic accuracy of the halo score for a clinical diagnosis of GCA, as well as a positive temporal artery biopsy.2 Here, we discuss the points raised by the authors.\n\nFirst, the authors propose that our study was focused on ‘test accuracy’. We fully agree with the authors on this point, as we included the term ‘diagnostic accuracy’ in our title and used it throughout our manuscript. Our definition of ‘diagnostic accuracy’ was similar to that reported in the references provided by the authors, that is, the ability of a test to discriminate between patients with the target condition and those without.3 4 It appears that the authors use a slightly distinct definition for ‘diagnostic accuracy’, that is, ‘a test’s added contribution to estimate the diagnostic probability of disease presence or absence’. This is actually the definition of ‘diagnostic yield’, as indicated by the reference provided by the authors.3 Sackett and Haynes have previously described …