Table 1

Descriptive data for the study, including 30-day mortality, any intensive care unit (ICU) admission and ICU admission >24 hours

Total cohort N=90 785Derivation cohort
N=63 715
Validation cohort
N=27 070
NValid %NValid %NValid %
Age (years)
 18–2911 05212.2774612.2330612.2
 30–4927 07829.818 87129.6820730.3
 50–6428 22731.119 83231.1839531.0
 65–7415 83717.411 20917.6462817.1
 75–8472568.051328.121247.8
 ≥8513351.59251.54101.5
Gender
 Female48 70853.734 08153.514 62754.0
 Male42 07746.329 63446.512 44346.0
Race
 Chinese64 86171.445 54571.519 31671.4
 Malay89799.963219.926589.8
 Indian80128.855808.824329.0
 Others89279.862649.826639.8
ASA Classification
 I22 04725.615 36625.5668126.1
 II49 43557.534 84457.814 59156.9
 III13 40515.6937215.5403315.7
 IV–VI10791.37401.23391.3
Anaemia
 None62 87872.544 31672.718 56272.0
 Mild13 00615.0908914.9391715.2
Moderate/severe10 86312.5755512.4330812.8
RDW
 >15.7847810.058559.9262310.4
 ≤15.776 06990.053 53590.122 53489.6
Grade of CKD
 G147 94860.033 65359.914 29560.1
 G223 63529.616 60329.5703229.6
 G351146.436576.514576.1
 G4–G532584.122744.09844.1
CVA
 Present15432.510682.44752.5
IHD
 Present42456.829766.812696.8
CHF
 Present7871.25441.22431.3
DM on insulin
 Present20033.114113.15923.1
Surgical risk
 Low48 04952.933 71552.914 33453.0
 Moderate39 01443.027 40243.011 61242.9
 High37224.125984.111244.2
Priority of surgery
 Elective72 33179.750 79179.721 54079.6
 Emergency18 45420.312 92420.3553020.4
30-day mortality5390.63740.61650.6
ICU admission17992.012321.95672.1
ICU admission >24 hours11451.37701.23751.4
  • Valid % = % of cases without missing data.

  • ASA, American Society of Anaesthesiologists’ physical status score; CHF, congestive heart failure; CKD, chronic kidney disease; CVA, cerebrovascular accident; DM, diabetes mellitus; IHD, ischaemic heart disease; RDW, red cell distribution width.