IJCS | Volume 31, Nº3, May/ June 2018

302 Martucheli et al. Cystatin C and acute coronary syndromes International Journal of Cardiovascular Sciences. 2018;31(3)290-307 Review Article Table 3 - Assessment of the studies’ quality according to the Newcastle-Ottawa Scale Author/Year Selection Comparability Outcomes Total points 1 2 3 4 5 6 7 8 Tonkin et al., 2015 15 * * * - ** * * * 8 Akerblom et al., 2012 16 * * * - ** * * * 8 Tang et al., 2015 17 * * * - * * * * 7 Fu et al., 2013 18 * * - - - * * * 5 Akgul et al., 2013 19 * * * - ** * - * 7 Widera et al.,2013 20 * - * - - * * * 5 Manzano- Fernández et al., 2012 21 * * * - ** * * * 8 Ristiniemi et al., 2012 22 * * * - * * * * 7 Silva et al., 2012 23 * * * - ** * * * 8 Sun et al., 2012 24 * * * - ** * * * 8 Kaski et al., 2010 25 * - * - * * * * 6 Taglieri et al., 2010 6 * * * - ** * * * 8 Derzhko et al., 2009 26 * - * - * * * * 6 Ichimoto et al., 2009 7 * * * - ** * * * 8 Kilic et al., 2009 27 * * * - ** * * * 8 García Acuña et al., 2009 28 * * * - ** * * * 8 Windhausen et al., 2009 5 * * * - * * * * 7 1- Representativeness of the exposed cohort: all studies were awarded one star, since the exposed cohort was somewhat representative of the average; 2 - Selection of the non-exposed cohort: in the studies that were awarded one star, the non-exposed cohort was drawn from the same community as the exposed cohort; in the studies that did not receive any star, no comparison was performed between patients exposed to high cystatin C levels and those who were not exposed; 3 - Ascertainment of exposure: studies that performed the measurement of cystatin C levels and informed which method was used were awarded one star, whereas no star was assigned if the study performed the measurements but did not inform the method used. 4- Demonstration that outcome of interest was not present at start of study: no study received a star, since patients had one of the outcome measures (acute coronary syndrome) in the beginning of the study; 5 - Comparability of cohorts on the basis of the design or analysis: studies that performed multivariate analysis, which included GFR or serum creatinine, among other variables, were awarded two stars; studies that performed multivariate analysis, which included variables other than GFR or serum creatinine, were awarded one star, whereas no star was awarded to studies that did not perform a multivariate analysis. 6 - Assessment of outcome; all studies were awarded one star, since assessment of outcome was performed independently, by the physicians. 7-Period of follow-up (long enough for outcomes to occur): studies in which patients were followed for at least 6 months were awarded one star, and studies in which patients were followed for less than 6 months received no star. 8 - Adequacy of follow up of cohorts: studies in which at least 90 of patients were followed until the end of the study or those with no description of significant losses were awarded one star.