Table 5.

Means, standard deviations, and gender comparisons for infant temperament measures.

	6-Month				12-Month
Temperament measure	Total N	Girls mean	Boys mean	Gender diff. t-value	Total N	Girls mean	Boys mean	Gender diff. t-value
IBQ fear	500	2.60	2.48	2.36*	709	3.20	3.10	2.02*
IBQ distress/anger	494	3.31	3.41	−1.89	705	3.76	3.79	−0.66
IBQ smiling and laughter	500	4.78	4.90	−1.95	713	5.08	5.12	−0.85
IBQ soothability	499	4.88	4.86	0.42	703	4.92	4.91	0.24
IBQ orienting	500	3.66	3.68	−0.36	703	3.66	3.59	0.95
IBQ activity level	500	4.13	4.13	0.08	703	4.34	4.47	−0.02
Fear—stranger	515	0.04	−0.04	1.23	802	0.023	−0.026	1.04
Fear—masks	557	0.05	−0.06	1.91	878	0.043	−0.047	1.87
Anger—arm restraint	537	0.01	−0.002	0.11	826	−0.02	0.02	−0.63
Anger—car seat	499	0.01	−0.001	0.28	775	−0.04	0.04	−1.35
Sadness—arm restraint	536	−0.01	0.01	−0.19	825	−0.03	0.03	−1.08
Sadness—car seat	499	−0.10	0.11	−2.85**	775	−0.05	0.04	−1.57
Positive affect—puppets	551	−0.001	0.01	−0.16	867	0.009	−0.008	0.34
Positive affect—peekaboo	534	−0.07	0.08	−2.76**	833	−0.045	0.050	−2.11*
Slides/interest	536	−0.08	0.06	−2.61**	877	−0.048	0.035	−2.11*
Activity level (BT and FP)	369	−0.14	0.16	−3.26***	837	−0.06	0.06	−2.74**
Lab-TAB fear	575	0.06	−0.04	1.99*	899	0.033	−0.029	1.67
Lab-TAB anger	564	0.05	−0.01	0.94	878	−0.02	0.04	−1.25
Lab-TAB sadness	563	−0.02	0.04	−1.29	878	−0.03	0.04	−1.57
Lab-TAB positive affect	565	−0.05	0.040	−1.87	894	−0.021	−0.010	−0.84

^*p < 0. 05;

^**p < 0. 01;

^***p < 0.001;

IBQ, Infant Behavior Questionnaire; Lab-TAB, Laboratory Temperament Assessment Battery; BT, Basket of Toys; FP, Free Play. IBQ measures are raw scores. Lab-TAB measures are z-scores.