Figure 2. Comparison between qPCR and TRF analysis of leukocyte telomere length in the healthy individuals and patients with bone marrow failure or idiopathic pulmonary fibrosis: linear correlation and Bland-Altman agreement.

Telomere length from 70 healthy individuals was measured by qPCR and Southern blot: (A) Linear regression plots of qPCR (T/S ratio) x TRF analysis (kb) measurements; solid line represents the data best fit (R² = 0.35); and (B) Bland-Altman plot for agreement analysis of qPCR (kb) and TRF analysis (kb). The bias±SD was 0.78±1.34 and limits of agreement (LoA) ranged from −1.90 to 3.47. Telomere length of 51 patients was measured by both methods: (C) Linear regression plots qPCR (T/S ratio) x TRF analysis (kb) measurements; solid line represents the data best fit (R² = 0.20) and (D) Bland-Altman plot for agreement analysis of qPCR (kb) and TRF analysis (kb). The bias±SD was 1.15±1.49 and the LoA ranged from −1.84 to 4.14.