In all 5 trials included in the final meta-analysis, PCT had a pooled sensitivity of 0.58 (95% Confidence interval (CI), 0.49–0.68) to osteomyelitis diagnosis in children (Fig. 4A) and a pooled specificity of 0.92 (95% CI, 0.90–0.93)to osteomyelitis diagnosis in children (Fig. 4B).The pooled positive LR was 4.05(95% CI, 2.30–7.14)(Fig. 5A), the pooled negative LR was 0.55 (95% CI, 0.37–0.82)(Fig. 5B), and the diagnostic OR was 8.93, 95% CI (5.46 − 14.61)(Fig. 5C), for the detection of osteomyelitis by PCT. The gene discussed is CALCA; the disease is osteomyelitis.