The present large cohort study, including more than 1000 participants with data on fasting blood variables and gold standard euglycemic insulin clamp tests, showed cross-sectionally that the newly introduced fasting insulin resistance index SPISE-IR had a similar degree of Spearman correlation with the insulin clamp index M/I-IR as other previously used fasting resistance indexes, QUICKI-IR, Log HOMA-IR, and Rev QUICKI-IR. Here, INS is linked to Insulin resistance.