The final NUTRIC score was found to be predictive (c-index = 0.783) of 28-day mortality.
Algorithms for hepatotoxicity (including codes for hepatic necrosis, toxic hepatitis and encephalopathy) and ALF (hepatic necrosis and encephalopathy) were also highly predictive (c-statistics = 0.88).
Further, these results demonstrate and it is reasonable to conclude that adding or replacing the APACHE II CHP with the Charlson index provides no practical improvement to the discriminative ability of such a predictive model (C = 0.808 vs C = 0.813).
We examined the relationship between measures of clinical utility (net benefit, event free life years) and predictive ability (c-statistic, binary c-statistic, continuous NRI 0), NRI with two cutpoints, binary NRI) using simulated data and the Framingham dataset.
The model was then tested on the remaining 25% of the population and demonstrated similar predictive ability (C = 0.630) (Figure 2B).
While one might expect that the two time constants (a and b) would be consistent from trial to trial for a given subject, one might also expect that the gains of the feedback of target velocity (g) and the amount of the predictive contribution (c) could depend on the speed profile, in the sense that a simpler velocity profile (SS) would be more predictable.
The predictive potential C increases with P0 and the prior odds, with typical values between 0.67 and 0.68 (Fig. 4e).
aCategories are not mutually exclusive; b PPV = positive predictive value; c NPV = negative predictive value; dOther = correlation coefficient, relative risk of association, kappa, percentage of agreement.
In the second modeling step, the introduction of the clinical specialty variable (obstetrics, yes/no) was not statistically significant, besides slightly decreasing the model's predictive capacity (C statistic = 0.84; 95% CI 0.80-0.88).
The predictive abilities (C statistics) for categorising patients into risk groups at one, five, and 10 years of follow-up were 0.711, 0.789, and 0.806 for CHADS2 and 0.845, 0.877, and 0.885 for CHA2DS2-VASc.
