Table 2

Discrimination and calibration of the non-laboratory INTERHEART Risk Score for incident cardiovascular disease

Outcome*/N (%)DiscriminationCalibration
C-stat (95% CI)Intercept
(95% CI)
Slope
(95% CI)
Original NL-IHRS
 Overall PURE population2284/100 475 (2.27)0.69 (0.68 to 0.70)−3.85 (−3.90 to 3.81)0.77 (0.73 to 0.82)
Geographic region
 South Asia525/12 130 (4.33)0.67 (0.64 to 0.69)−3.03 (−3.12 to 2.94)0.75 (0.65 to 0.86)
 China568/38 431 (1.48)0.69 (0.67 to 0.71)−4.06 (−4.14 to 3.97)0.81 (0.71 to 0.91)
 Southeast Asia137/6892 (1.99)0.73 (0.69 to 0.77)−4.17 (−4.38 to 3.97)0.92 (0.72 to 1.12)
 Africa50/1291 (3.87)0.64 (0.56 to 0.72)−3.27 (−3.57 to 2.97)0.75 (0.36 to 1.15)
 North America/Europe523/16 148 (3.24)0.69 (0.67 to 0.72)−3.70 (−3.80 to 3.59)0.77 (0.68 to 0.87)
 Middle East129/5626 (2.29)0.74 (0.70 to 0.78)−4.00 (−4.21 to 3.79)1.06 (0.86 to 1.26)
 South America352/19 957 (1.76)0.72 (0.69 to 0.75)−4.43 (−4.57 to 4.29)0.87 (0.77 to 0.98)
Country income status
 HIC328/12 160 (2.70)0.68 (0.65 to 0.71)−3.85 (−3.98 to 3.72)0.72 (0.60 to 0.83)
 MIC1400/75 597 (1.85)0.71 (0.70 to 0.73)−4.08 (−4.14 to 4.02)0.85 (0.80 to 0.91)
 LIC556/12 718 (4.37)0.67 (0.64 to 0.69)−3.01 (−3.10 to 2.93)0.76 (0.65 to 0.86)
Recalibrated NL-IHRS
 Overall PURE population2284/100 475 (2.27)0.72 (0.71 to 0.73)−0.003 (−0.18 to 0.17)1 (0.95 to 1.05)
Geographic region
 South Asia525/12 130 (4.33)0.67 (0.64 to 0.69)0 (−0.42 to 0.42)1 (0.86 to 1.14)
 China568/38 431 (1.48)0.69 (0.67 to 0.71)0 (−0.49 to 0.49)1 (0.88 to 1.12)
 Southeast Asia137/6892 (1.99)0.73 (0.69 to 0.77)0 (−0.80 to 0.80)1 (0.78 to 1.22)
 Africa50/1291 (3.87)0.64 (0.56 to 0.72)0 (−1.62, 1.62)1 (0.48 to 1.52)
 North America/Europe523/16 148 (3.24)0.69 (0.67 to 0.72)0 (−0.40 to 0.40)1 (0.88 to 1.12)
 Middle East129/5626 (2.29)0.74 (0.70 to 0.78)0 (−0.65 to 0.65)1 (0.81 to 1.19)
 South America352/19 957 (1.76)0.72 (0.69 to 0.75)0 (−0.48 to 0.48)1 (0.87 to 1.13)
Country income status
 HIC328/12 160 (2.70)0.69 (0.66 to 0.71)−0.48 (−0.98 to 0.01)0.91 (0.76 to 1.06)
 MIC1400/75 597 (1.85)0.72 (0.71 to 0.74)0.22 (−0.03 to 0.46)1.05 (0.98 to 1.11)
 LIC556/12 718 (4.37)0.66 (0.64 to 0.69)−0.01 (−0.43 to 0.40)0.99 (0.85 to 1.13)
  • *Cardiovascular disease defined as cardiac death, stroke, myocardial infarction, heart failure and revascularisation.

  • C-stat, concordance statistic; HIC, high-income countries; LIC, low-income country; MIC, middle-income country; NL-IHRS, non-laboratory INTERHEART risk score; PURE, Prospective Urban Rural Epidemiology.