For IGFBP2 values less than 262.8 ng/ml, the likelihood ratio for the presence of PAH was 0.2 (95% confidence interval [CI] 0.15–0.28), while for values of 262.8 or greater, the likelihood ratio was 3.9 (95% CI 2.79–5.58). The gene discussed is IGFBP2; the disease is pulmonary arterial hypertension.