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Editorial
. 2017 Nov;5(21):436.
doi: 10.21037/atm.2017.08.22.

Development of scoring system for risk stratification in clinical medicine: a step-by-step tutorial

Affiliations
Editorial

Development of scoring system for risk stratification in clinical medicine: a step-by-step tutorial

Zhongheng Zhang et al. Ann Transl Med. 2017 Nov.

Abstract

Risk scores play an important role in clinical medicine. With advances in information technology and availability of electronic healthcare record, scoring systems of less commonly seen diseases and population can be developed. The aim of the article is to provide a tutorial on how to develop and validate risk scores based on a virtual dataset by using R software. The dataset we generated including numeric and categorical variables and firstly the numeric variables would be converted to factor variables according to cutoff points identified by the LOESS smoother. Then risk points of each variable, which are related to the coefficients in logistic regression, are assigned to each level of the converted factor variables and other categorical variables. Finally, the total score is calculated for each subject to represent the prediction of the outcome event probability. The original dataset is split into training and validation subsets. Discrimination and calibration are evaluated in the validation subset. R codes with explanations are presented in the main text.

Keywords: LOESS smoothing; Scoring system; risk stratification.

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Conflict of interest statement

Conflicts of Interest: The authors have no conflicts of interest to declare.

Figures

Figure 1
Figure 1
LOESS smoothing curve plotting the probability of death against age. Note the age is not linearly associated with the probability and we need to identify cut points at which y value changes the most.
Figure 2
Figure 2
LOESS smoothing curve plotting the probability of death against lac.
Figure 3
Figure 3
Predicted probability of death versus the number of observed survivors and non-survivors.
Figure 4
Figure 4
The predicted probability is plotted against the observed probability. A variety of statistics are displayed on the top left.

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