Three studies measured CXCL1 [38–40] and identified statistically significant differences in TB patients, but were not analyzed for diagnostic performance due to small sample sizes and different sample types: n = 44 to 88 for plasma [38]; n = 11 to 27 for serum [39]; and n = 11 to 27 and n = 32 to 72 for saliva [39,40]. This evidence concerns the gene CXCL1 and tuberculosis.