Bridging Gaps in Newborn Screening: A Comparative Study of Point-of-Care Testing Versus Traditional Reference Laboratory Method for Congenital Hypothyroidism.

OBJECTIVE

This study aimed to compare the reliability, agreement, and practical application (turnaround time) of a point-of-care testing (POCT) device using two different reagents versus the traditional reference laboratory method for thyroid-stimulating hormone (TSH) measurement in newborn congenital hypothyroidism screening.

METHODOLOGY: This prospective cross-sectional method-comparison study included 122 term newborns at a mother and child hospital in Surabaya, Indonesia. Heel-prick capillary blood samples were simultaneously analyzed using the Standard F-200 POCT device with two reagents (Group 1: n = 62, Standard™ F TSH-II; Group 2: n = 60, FastClear F TSHII) and compared to the standard dried blood spot method (GSP® Neonatal hTSH, PerkinElmer) as reference. Analyses included Pearson and Spearman correlations, linear regression, Bland-Altman plots, intraclass correlation coefficient (ICC), Cohen's Kappa, and mean difference tests.

RESULTS

Strong positive correlations were observed in both Group 1 (Pearson's r = 0.87, Spearman's ρ = 0.85; p <0.001) and Group 2 (Pearson's r = 0.88, Spearman's ρ = 0.91; p <0.001). Bland-Altman analysis showed minimal systematic bias with acceptable agreement between the two techniques. The ICC values indicated excellent reliability (Group 1: 0.89; Group 2: 0.91). High categorical agreement was confirmed by Cohen's Kappa values of 0.85 and 0.87 (p <0.001). No significant differences in mean TSH levels were found between the POCT and reference methods. The POCT turnaround time was 30 minutes, significantly shorter than the 15-22 days required for the traditional method.

CONCLUSION

POCT devices present a promising alternative to traditional reference screening method for congenital hypothyroidism.