Fig. 6

Spearman’s coefficient of Rank correlation (Rho) between chloride values achieved in the sweat test (mmol/L) and sweat weight (mg) showed there was a positive correlation between sweat chloride values and sweat weight. a All samples: Sample size = 460 (sweat weight below of 75 mg were excluded). Rho = − 0.482; 95% confidence interval for Rho = − 0.549 to − 0.409. p-value < 0.0001. CCC-CF = 26/460 (5.7%); CCC-borderline = 108/460 (23.5%); CCC-health = 97/460 (21.1%); SPC-CF = 5/460 (1.1%); SPC-borderline = 19/460 (4.1%); SPC-health = 28/460 (6.1%); TPC-CF = 21/460 (4.6%); TPC-borderline = 75/460 (16.3%); TPC-health = 81/460 (17.6%). b CCC. Sample size = 231. Rho = − 0.508; 95% confidence interval for Rho = − 0.598 to − 0.406. CCC-CF = 26/231 (11.26%); CCC-borderline = 108/231 (46.75%); CCC-health = 97/231 (41.99%). p-value < 0.0001. c SPC. Sample size = 52. Rho = − 0.361; 95% confidence interval for Rho = − 0.577 to − 0.098. SPC-CF = 5/52 (9.62%); SPC-borderline = 19/52 (36.54%); SPC-health = 28/52 (53.85%). p-value = 0.0086. d TPC. Sample size = 177. Rho = − 0.470; 95% confidence interval for Rho = − 0.577 to − 0.346. TPC-CF = 21/177 (11.86%); TPC-borderline = 75/177 (42.76%); TPC-health = 81/177 (45.76%). p-value < 0.0001. CCC, continuous constant current; SPC, sinusoidal pulsed current; TPC, triangular pulsed current; CF, cystic fibrosis. Chloride values (mmol/L): (i) CF – ≥ 60 mmol/L; (ii) borderline – between ≥ 30 to < 60 mmol/L; (iii) health – > 30 mmol/L. The chloride concentration is shown as milliequivalent by liter (mmol/L). Also, the sweat weight is shown as milligrams