Table 2.

Intraclass Correlation Coefficients (ICCs) between Session 1 and Session 2 (Examiner 1) and between Examiner 1 and Examiner 2 (average of measures of two measures).

Heterophoria measure	Test distance	Intra-examiner repeatability ICC (95% confidence limits)	Inter-examiner repeatability ICC (95% confidence limits)
Alternating prism cover test	6 m	0.877 (0.720–0.949)	0.914 (0.796–0.965)
	40 cm	0.929 (0.829–0.971)	0.948 (0.875–0.979)
Von Graefe	6 m	0.777 (0.519–0.906)	0.850 (0.655–0.937)
	40 cm	0.783 (0.529–0.908)	0.860 (0.661–0.944)
Howell Card	3 m	0.804 (0.570–0.918)	0.903 (0.775–0.960)
	33 cm	0.9612 (0.906–0.984)	0.984 (0.960–0.994)
Maddox Rod	6 m	0.907 (0.780–0.962)	0.952 (0.884–0.981)
	40 cm	0.899 (0.764–0.959)	0.867 (0.131–0.965)