highly significantP < .001
The pooled INB was estimated at $62.17 (95% confidence interval, $7.12–$117.21) in LICs, with a highly significant heterogeneity (χ 2 = 33.96; df = 6; P < .001; I 2 = 82.3%), whereas the pooled INB in LMICs was $82.46 (95% confidence interval, $54.52–$110.41) with no heterogeneity (χ 2 = 8.46; df = 11; P = .67; I 2 = 0%).