Table 4

Horizontal prism cover test measurements

	Day 1			Day 1			Day 5
	Controls	Median	Range	Patients	Median	Range	Patients	Median	Range
PBIn = prism base-in; PBOut = prism base-out; Δ = prism dioptres.
Near	n = 10	3Δ PBIn	8Δ PBIn to 8Δ PBOut	n = 82	8Δ PBIn	25Δ PBIn to 35Δ PBOut	n = 67	6Δ PBIn	30Δ PBIn to 18Δ PBOut
Distance	n = 10	1.5Δ PBIn	2Δ PBIn to 4Δ PBOut	n = 83	2Δ PBIn	12Δ PBIn to 4Δ PBOut	n = 66	4Δ PBOut	14Δ PBIn to 16Δ PBOut
Primary position				n = 38	2Δ PBIn	10Δ PBIn to 4Δ PBOut	n = 38	4Δ PBOut	14Δ PBIn to 16Δ PBOut
Right gaze				n = 38	1.5Δ PBIn	4Δ PBIn to 8Δ PBOut	n = 38	8Δ PBOut	12Δ PBIn to 18Δ PBOut
Left gaze				n = 38	2Δ PBIn	6Δ PBIn to 8Δ PBOut	n = 38	7Δ PBOut	14Δ PBIn to 18Δ PBOut