A novel approach using a polarized nonius test to evaluate the near point of convergence

The Nonius method demonstrated a median break point of 8.37 cm, significantly higher than the other methods, NPC1: 6.63 cm, and NPC2: 7.17 cm. Sensitivity for detecting CI symptoms was 92.6 % for the NPC3, which outperformed NPC1 (77.8 %) and NPC2 (74.1 %). NPC3 exhibited low specificity (7.4 %). Correlations between NPC measurements and CISS scores were weak and nonsignificant, though the strongest correlation was observed for NPC3 CONCLUSION: The Nonius polarized target method shows benefits compared to traditional methods in measuring NPC. This study provides a more sensitive method to measure convergence ability, reducing variability across clinical settings, and enhancing the reliability of assessments in both research and practice.