Age-Group Differences in Cognitive Ability Measures

	Younger		Middle aged		Older
Ability measures	M	SD	M	SD	M	SD	F (2, 1107)	Age-group comparisons (α = .05)
Alphabet span simple	47.74	10.58	41.43	10.10	37.79	9.00	100.77***	Y > M > O
Choice RT Both hands (log)	−5.76	0.20	−5.92	0.29	−6.01	0.28	107.84***	Y > M > O
Computation span simple	41.20	15.33	34.62	14.86	28.75	12.46	80.40***	Y > M > O
CVLT-Delayed	13.67	2.46	11.37	3.44	10.61	4.14	119.27***	Y > M > O
CVLT-Immediate	60.36	10.05	52.98	11.93	49.17	11.20	111.60***	Y > M > O
Cube comparison correct	23.68	8.01	17.20	6.59	14.61	5.84	182.72***	Y > M > O
Digit symbol substitution	67.46	12.96	51.77	14.19	45.83	12.30	298.84***	Y > M > O
Digit symbol recall	7.46	1.97	6.19	2.45	4.43	2.40	191.71***	Y > M > O
Inference test correct	14.16	3.56	12.23	4.59	11.63	4.35	42.26***	Y > M, Y > O
Letter sets correct	21.40	4.90	16.86	5.85	14.78	5.64	167.61***	Y > M > O
MAB Information	25.69	6.38	23.54	7.60	24.34	7.41	8.34***	Y > M
Meaningful memory	15.29	4.14	12.39	4.93	11.46	4.79	75.11***	Y > M, Y > O
Number comparison correct	57.19	10.98	46.76	11.90	42.67	10.26	195.68***	Y > M > O
Paper folding correct	12.03	4.16	7.84	3.76	6.56	3.33	238.79***	Y > M > O
Reading comprehension	31.60	6.08	26.62	9.03	25.11	8.60	74.82***	Y > M, Y > O
Shipley vocabulary	30.02	4.21	32.15	6.05	34.47	4.62	98.09***	Y > M > O
Simple RT (log)	−5.57	0.22	−5.74	0.30	−5.85	0.27	117.50***	Y > M > O
Stroop color–word (log)	3.85	0.25	3.60	0.29	3.46	0.32	198.80***	Y > M > O
Trailmaking B-A (log)	−3.24	0.84	−3.59	0.68	−3.83	0.73	64.56***	Y > M > O
WAIS-III Information	19.34	4.55	19.39	5.28	20.64	4.63	11.25***	Y < O, M < O

Note. RT = reaction time; Y = younger; M = middle aged; O = older; CVLT = California Verbal Learning Test; MAB = Multidimensional Aptitude Battery.

^***p < .001.