CRP and major depressive disorder: Similarly, it has been estimated that only 47% of depression patients whose scores are above the clinical threshold had a CRP level ≥ 0.3 mg/dl and only 29% had a CRP level ≥ 0.5 g/dl (27, 37), suggesting an essential but perhaps not sufficient role of peripheral inflammation for the emergence of depression and a more pronounced relevance for a subset of depressed individuals.