Table 6.

Reliability Coefficients, Statistical Significance of Difference and Ratio Between Groups’ Reliability Coefficients for Each Test.

Tests	Parts	Prosopagnosics		Controls		p		Ratio
		Cronbach’s alpha	Adjusted split-half	Cronbach’s alpha	Adjusted split-half	Cronbach’s alpha	Unadjusted split-half	Cronbach’s alpha	Adjusted split-half
3.1. CFMT		0.26	0.31	0.82	0.83	0.01*	0.05	3.15	2.68
3.2. Cars	CCMT	0.87	0.88	0.88	0.89	0.83	0.89	1.01	1.01
	Car-expertise	0.69	0.72	0.56	0.58	0.49	0.58	0.81	0.81
3.3. Surprise recognition	Surprise	–	0.30	–	0.66	–	0.32	–	2.20
	Control	–	0.65	–	0.76	–	0.62	–	1.17
3.4. Composite face task	Up-algn	0.85	0.86	0.94	0.95	0.04*	0.16	1.11	1.10
	Up-misalgn	0.86	0.87	0.92	0.93	0.27	0.42	1.07	1.07
	Inv-algn	0.86	0.87	0.92	0.92	0.28	0.43	1.07	1.06
	Inv-misalgn	0.83	0.84	0.91	0.92	0.24	0.40	1.10	1.10
3.5. Featural and configural sensitivity task	Features	0.97	0.97	0.94	0.94	0.18	0.35	0.97	0.97
	Configuration	0.97	0.97	0.96	0.96	0.65	0.74	0.99	0.99
3.6. Gender recognition		0.67	0.70	0.69	0.72	0.88	0.91	1.03	1.03
3.7. Facial motion advantage	Dynamic	–	0.52	–	0.44	–	0.83	–	0.85
	Static	–	0.17	–	0.50	–	0.48	–	2.94

CFMT = Cambridge Face Memory Test; CCMT = Cambridge Car Memory Test; up = upright; inv = inverted; algn = aligned; mislagn = misaligned. Reliability coefficients were calculated with bootstrapped Spearman–Brown adjusted split-half method and, where possible, with Cronbach’s alpha. Statistical significance of difference between groups’ reliability coefficients was calculated as difference between correlations for unadjusted split-half reliability coefficients and with the Bonett formula for Cronbach’s alpha (Bonett, 2003). The ratio between prosopagnosics and controls reliability coefficients was calculated by dividing controls reliability coefficients by prosopagnosics reliability coefficients. ^* Statistically significant p values