We appreciate the kind interest shown by Calle-Urra et al. in our article on the validity of the minimum basic data set (MBDS) for research into outcomes in the care of acute coronary syndrome.1 The authors wished to highlight the problems in the coding quality of the MBDS, which they considered important among the limitations of our study. However, as our objective was to evaluate the concordance between a clinical registry (DIOCLES) and the MBDS, the coding quality was, in our opinion, a study variable whose result should not be viewed as a limitation at all.
The study published on the Murcia Health Service website,2 which formed the basis for their doubts about the quality of the MBDS had a different objective to ours; it lightly touched on the coding quality, and it did so differentiating the diagnoses of ST-elevation acute myocardial infarction and non–ST-elevation acute myocardial infarction—something which we did not analyze. The Murcia Health Service study used as its study sample 897 registered episodes that took place in 9 hospitals in Murcia over 2 nonconsecutive 6-month periods in 2012 and 2013, and the authors reported that they considered it unnecessary to obtain confidence intervals, meaning that the scope of their method is merely descriptive and therefore does not allow any inference from their results. Nonetheless, although they did not distinguish between non–ST-elevation acute myocardial infarction and unstable angina, it would seem that they found a high degree of concordance in the coding for acute myocardial infarction (a variable that we did include in our study), as they reported discrepancies in only 3.6% of the clinical records reviewed. Regardless, as we reflect on the conclusions of our study, we concur that there would seem to be room for improvement in the coding quality of the MBDS, but we believe that this can only be established using scientific methods subject to peer-review; this should also be the case for assessing the impact of the updated version of the International Classification of Diseases that the MBDS started to use in 2016.