. Author manuscript; available in PMC: 2013 Aug 10.

Published in final edited form as: Optom Vis Sci. 2010 Mar;87(3):168–175. doi: 10.1097/OPX.0b013e3181d1d954

TABLE 2.

Comparison of alternate cover test measurements with long vs. short dissociation protocol

	Absolute mean (SD) difference (Δ)	Range (Δ)
All examiners combined
Ortho w/short dissociation (n = 268)	1.49 (2.3)^a	0–12
Nonortho w/short dissociation (n = 452)	1.56 (1.7)^a	0–12.5
Overall	1.53 (1.9)^a	0–12.5

Experienced examiners
Ortho w/short dissociation (n = 67)	2.14 (2.1)^a	0–12
Nonortho w/short dissociation (n = 173)	1.44 (1.4)^a	0–7
Overall	1.64 (1.7)^a	0–12

Inexperienced examiners shown narrow distribution
Ortho w/short dissociation (n = 94)	1.17 (2.3)^a	0–9
Nonortho w/short dissociation (n = 146)	1.57 (1.6)^a	0–7
Overall	1.41 (1.9)^a	0–9

Inexperienced examiners shown wide distribution
Ortho w/short dissociation (n = 107)	1.36 (2.2)^a	0–8
Nonortho w/short dissociation (n = 133)	1.71 (2.1)^a	0–12.5
Overall	1.55 (2.2)^a	0–12.5

Differences are the absolute value of the measurement by long dissociation minus the measurement by short dissociation. “n” indicates number of measurements.

All mean differences were significantly greater than zero (p < 0.0001).