TABLE III.

CORRELATIONS AMONG STUDY VARIABLES, INCLUDING DEMOGRAPHICS, APOE ε4 STATUS, FLIGHT SIMULATOR PERFORMANCE, REY AVLT COMPOSITE SCORES AND LOBAR VOLUMES^*.

	Age	Years of Education	APOE ε4 Status	Flight Hours Past Month	Accumulated Flight Hours	Aviation Expertise	Flight Performance Baseline	Flight Performance Slope (2 yr)	Rey AVLT Composite Baseline	Hippocampus	Parietal Lobe Volume	Temporal Lobe Volume	Occipital Lobe Volume	Basal Ganglia Volume	Cerebellar Volume	Prefrontal Cortex Volume	Whole Brain Volume	TIV
Age1		0.07	−0.07	0.01	−0.15	−0.13	−0.41	−0.01	−0.36	−0.32	−0.35	−0.27	−0.15	−0.36	−0.05	−0.42	−0.39	0.16
Years of Education2	0.07		0.24	0.06	0.01	0.32	0.05	−0.06	0.13	0.01	−0.03	−0.03	−0.14	−0.05	−0.02	−0.03	−0.09	0.06
APOE ε4 status3	−0.07	0.24		0.03	−0.14	−0.08	0.03	−0.10	−0.20	0.00	0.05	0.19	0.01	0.12	0.03	0.08	0.13	0.07
Flight hours past month4	0.01	0.06	0.03		0.82	0.40	0.14	0.18	0.02	0.01	−0.06	−0.01	0.05	0.28	−0.04	−0.11	−0.06	0.38
Accumulated Flight Hours5	−0.15	0.01	−0.14	0.82		0.37	0.23	0.15	0.13	0.07	0.03	0.01	0.07	0.26	0.02	−0.07	0.05	0.27
Aviation Expertise6	−0.13	0.32	−0.08	0.40	0.37		0.28	0.08	0.10	0.17	−0.13	−0.06	−0.08	0.24	−0.04	0.02	−0.09	0.21
Flight Performance Baseline7	−0.41	0.05	0.03	0.14	0.23	0.28		−0.16	0.18	0.07	0.26	0.20	0.31	0.32	0.22	0.32	0.34	0.06
Flight Performance Slope (2 yrs)8	−0.01	−0.06	−0.10	0.18	0.15	0.08	−0.16		−0.12	−0.17	0.10	0.21	0.11	0.01	−0.13	0.17	0.06	0.12
Rey AVLT Composite Baseline9	−0.36	0.13	−0.20	0.02	0.13	0.10	0.18	−0.12		0.30	0.19	0.13	0.12	0.30	0.07	0.18	0.14	−0.32
Hippocampus10	−0.32	0.01	0.00	0.01	0.07	0.17	0.07	−0.17	0.30		0.21	0.19	0.19	0.28	0.16	0.13	0.26	0
Parietal Lobe Volume11	−0.35	−0.03	0.05	−0.06	0.03	−0.13	0.26	0.10	0.19	0.21		0.74	0.53	0.47	0.21	0.70	0.81	0
Temporal Lobe Volume11	−0.27	−0.03	0.19	−0.01	0.01	−0.06	0.20	0.21	0.13	0.19	0.74		0.46	0.41	0.17	0.67	0.73	0
Occipital Lobe Volume11	−0.15	−0.14	0.01	0.05	0.07	−0.08	0.31	0.11	0.12	0.19	0.53	0.46		0.33	−0.01	0.46	0.50	0
Basal Ganglia Volume11	−0.36	−0.05	0.12	0.28	0.26	0.24	0.32	0.01	0.30	0.28	0.47	0.41	0.33		0.13	0.48	0.54	0
Cerebellar Volume11	−0.05	−0.02	0.03	−0.04	0.02	−0.04	0.22	−0.13	0.07	0.16	0.21	0.17	−0.01	0.13		0.07	0.20	0
Prefrontal Volume11	−0.42	−0.03	0.08	−0.11	−0.07	0.02	0.32	0.17	0.18	0.13	0.70	0.67	0.46	0.48	0.07		0.81	0
Whole Brain Volume11	−0.39	−0.09	0.13	−0.06	0.05	−0.09	0.34	0.06	0.14	0.26	0.81	0.73	0.50	0.54	0.20	0.81		0
TIV12	0.16	0.06	0.07	0.38	0.27	0.21	0.06	0.12	−0.32	0	0	0	0	0	0	0	0

^*Pearson correlation coefficients in bold were significant (P < 0.05).

¹Age: measured at the time of the baseline flight simulator performance.

²Years of education are truncated to 20 yr.

³APOE ε4 genotyping is based on genomic DNA extracted from frozen blood/buccal mucosa/saliva samples.

⁴Flight hours past month: number of hours flown (nonsimulator) in the month immediately preceding the baseline visit.

⁵Accumulated Flight Hours is the average yearly increase in flight hours during the course of follow-up. At each annual follow-up, the number of flight hours accumulated to date were recorded, based on self-report and by verification of the pilot’s log book whenever possible.

⁶Aviation expertise: measured by FAA proficiency ratings at entry into the study which provide an ordinal measure of lifetime aviation training and experience.

⁷Baseline Flight Performance: a composite z-score of the four flight tasks; (see Taylor 2007 for details).

⁸Slope of Flight Performance: linear slope of the flight performance from baseline to year 2 visit; [see Taylor (26) for details].

⁹Rey AVLT composite score is the average of the immediate and delayed recall z-scores [see Adamson et al. (1) for details].

¹⁰Hippocampal volumes were residualized on total intracranial volume (TIV) to adjust for head size.

¹¹Volumes of parietal, temporal, occipital, basal ganglia, cerebellum, prefrontal cortex, and whole brain were residualized on TIV to adjust for head size.

¹²TIV: total intracranial volume (cc).