Abstract The purpose of this study was to empirically verify the existence or not of a distortion in the comparability of information when inflationary effects are omitted from financial statements. Although inflation has been under control in Brazil since the Plano Real, with indices well below those recorded in the 1980s and 1990s, discussing the need for accounting recognition of the effects of inflation remains an extremely relevant and pertinent issue in light of the proposal of accounting to produce faithful information that closely reflects the economic reality in which organizations operate. The results of the research show that financial accounting has been directly affected by the omission of inflationary effects in financial statements, drawing attention to the negative effects this has caused on the quality of the information produced. In order to operationalize the research, the Balance Sheet Monetary Correction (BSMC) was applied to the balance sheets of Brazilian companies from the siderurgical and metallurgical sector listed on the BM&FBOVESPA in the period from 1996 to 2016. Based on the variables net income, return on equity (ROE), and return on assets (ROA), and two conceptual axes of comparability (between entities and between periods), the statistical parameters were developed and the hypotheses were defined, which were tested using the Student t parametric test. This article shows the damage caused to the decision-making process of the external users for whom financial statements are intended when these are prepared neglecting the effects of inflation. This is verifiable through the analyses of the results obtained, including the observation of significant distortions between the means of the corrected indicators and the means of the historical indicators, such as in the case of net income in 2001, 2002, 2012, 2013, 2014, and 2016 (33.98%, 91.92%, -65.54%, -30.01%, -53.59%, and 26.30% variation, respectively), of ROE (-67.16%, -61.43%, -53.06%, -63.46%, -133.81%, and 65.00% variations in 2008, 2009, 2010, 2011, 2014, and 2015, respectively), and of ROA (-26,70%, -41.14%, -33,34%, -43,49%, 98,83%, and -413,68% in 2005, 2009, 2010, 2011, 2012, and 2014, respectively).