Traumatic Brain Injury and Its Relationship to Previous Convictions, Aggression, and Psychological Functioning in Dutch Detainees

Figures & data

Table 1. Sample Characteristics

	Detainees		Non-incarcerated controls		Significance
TBI history (yes/no)	127/154		15/36		X2(1) = 3.77 p = .05
Education (low/middle/high)	101/147/31		2/14/35		X2(2) = 91.34 p < .001
	Mean	Sd	Mean	Sd
Number of TBIs	1.33	4.02	0.51	0.92	t(229.94) = 1.43 p = .15
Age	38.29	12.39	42.94	17.43	t(229.41) = − 2.15 p = .03
ERQ	35.60	9.51	37.84	7.21	t(226.90) = −1.55 p = .12
CTQ	41.86	16.79	38.91	11.23	t(224.74) = 1.17 p = .24
AVL-AV	27.44	10.67	22.29	8.04	t(229.87) = 3.19 p = .002
BIS-11	64.18	11.96	58.07	9.25	t(93.28) = 2.60 p = .01
SCIL 18+	19.51	5.05	24.65	3.04	t(230) = −6.91 p < .001
Current sentence length	38.52	20.48
Previous convictions	10.13	6.28
Previous prison sentences	3.19	1.86

This table denotes the prevalence of experienced TBI, as well as the means and standard deviations for the number of experienced TBIs, age, emotion regulation (ERQ), childhood trauma (CTQ), aggression (AVL-AV), impulsivity (BIS-11), and scores on a screener for mild intellectual disability (SCIL18+). Please note that TBI history, and education were computed for n = 281 detainees, whereas other variables are computed for n = 183.

Figure 1. Causes of TBI. This figure depicts the self-reported causes of the TBI. Please note that one participant may report multiple causes of TBI

Table 2. Pooled ANCOVA Results

	Model 1						Model 2
	Variable	SSQ (type2)	Df	F-value	p-value	Eta2	Variable	SSQ (type2)	Df	F-value	p-value	Eta2
Aggression	TBI	2823.40	1.00	29.57	P < .001	0.14	TBI	2823.40	1.00	30.90	P < .001	0.14
(r2 =.22/r2 =.26)	Age	668.01	1.00	6.96	P < .01	0.03	Age	668.01	1.00	7.28	P < .01	0.03
	Education	265.75	2.00	1.38	0.25	0.01	Education	265.75	2.00	1.44	0.24	0.01
	Nationality	772.90	7.00	1.15	0.33	0.04	Nationality	772.90	7.00	1.21	0.30	0.04
	Residual	16198.60					TBI caused by violence	808.11	1.00	8.89	P < .001	0.04
							Residual	15390.49
Impulsivity	TBI	500.43	1.00	2.75	0.10	0.02
(r2 =.11)	Age	472.76	1.00	2.95	0.09	0.02
	Education	770.19	2.00	2.27	0.10	0.03
	Nationality	995.36	7.00	0.74	0.63	0.04
	Residual	23324.36
Emotion regulation	TBI	21.08	1.00	0.19	0.67	0.00
(r2 =.04)	Age	4.13	1.00	0.02	0.87	0.00
	Education	355.33	2.00	1.78	0.17	0.02
	Nationality	341.99	7.00	0.41	0.89	0.02
	Residual	15730.94
Childhood trauma	TBI	1104.54	1.00	3.89	0.05	0.02
(r2 =.09)	Age	7.17	1.00	0.01	0.91	0.00
	Education	119.74	2.00	0.15	0.86	0.00
	Nationality	3347.09	7.00	1.60	0.13	0.07
	Residual	46755.88
Intelligence	TBI	15.64	1.00	0.77	0.38	0.00
(r2 =.25)	Age	29.33	1.00	1.41	0.23	0.01
	Education	789.41	2.00	19.31	0.00	0.17
	Nationality	317.66	7.00	2.20	0.03	0.07
	Residual	3489.67
Number of convictions	TBI	118.97	1.00	1.04	0.31	0.02
(r2 =.09)	Age	138.42	1.00	1.83	0.18	0.02
	Education	90.20	2.00	0.47	0.63	0.01
	Nationality	298.74	7.00	0.33	0.94	0.04
	Residual	6534.04
Sentence length	TBI	116.79	1.00	0.15	0.70	0.00
(r2 =.06)	Age	1162.42	1.00	2.17	0.14	0.02
	Education	599.74	2.00	0.36	0.70	0.01
	Nationality	2949.53	7.00	0.32	0.94	0.04
	Residual	71575.22
Number of incarcerations (past 5 years)	TBI	5.81	1.00	0.79	0.37	0.01
(r2 =.17)	Age	27.98	1.00	3.56	0.06	0.04
	Education	32.33	2.00	1.69	0.19	0.05
	Nationality	41.33	7.00	0.62	0.74	0.07
	Residual	525.93

This table shows the pooled univariate ANCOVA results for the difference between detainees with and without a history of TBI, on aggression, impulsivity, emotion regulation, childhood trauma, and intelligence. In model two, a covariate is added to the model assessing differences between detainees with and without a history of TBI on aggression, which reflects whether TBI was ever the result of violence. Results indicate that detainees with a history of TBI have significantly different levels of aggression, but not in levels of impulsivity, emotion regulation, childhood trauma, and intelligence. Differences in aggression remain significant when adding “TBI caused by violence” as a covariate. TBI = traumatic brain injury, SSQ = sum of squares, significant results are presented in bold letters.

Table 3. Logistic Regression Table for Prior Convictions

Predictor		Odds Ratio	SE	T	df	P	CI: 2.5%	CI: 97.5%
(Intercept)		23.59	0.84	3.77	166.00	<0.001	4.50	123.65
TBI		3.33	0.44	2.74	166.55	<0.01	1.40	7.90
Age		0.95	0.02	−3.00	166.91	<0.01	0.92	0.98
Education
	Medium (vs Low)	0.97	0.46	−0.06	167.29	0.95	0.39	2.39
	High (vs Low)	0.28	0.60	−2.11	162.09	0.04	0.09	0.92
Nationality
	Turkish-Dutch (vs. Dutch)	1.25	1.12	0.20	168.90	0.84	0.14	11.44
	Marrocan-Dutch (vs. Dutch)	0.55	0.78	−0.76	167.58	0.45	0.12	2.58
	Antillian-Dutch (vs. Dutch)	0.47	0.69	−1.11	168.90	0.27	0.12	1.82
	Surinam-Dutch (vs. Dutch)	1.59	1.16	0.40	168.98	0.69	0.16	15.78
	Surinam (vs. Dutch)	1.16	0.89	0.16	169.02	0.87	0.20	6.73
	Other (vs. Dutch)	0.43	0.73	−1.15	162.58	0.25	0.10	1.82
	Other-Dutch (vs. Dutch)	0.31	0.91	−1.29	168.98	0.20	0.05	1.86
Pseudo R^2 =.15	(p < .01)

Summary of the logistic regression analysis, which assessed if TBI history predicts whether or not detainees had any prior convictions, controlling for background variables. Results indicate that detainees with a TBI history were 3.3 times more likely to have prior convictions. SE = standard error, df = degrees of freedom, p = p-value, CI = 95% confidence interval.

Table 4. Logistic Regression Table for Prior Jail Sentence

Predictor		Odds Ratio	SE	T	df	P	CI: 2.5%	CI: 97.5%
(Intercept)		6.06	0.74	2.45	161.21	0.02	1.42	25.85
TBI		1.90	0.37	1.73	165.55	0.09	0.91	3.95
Age		0.98	0.02	−1.33	165.31	0.18	0.95	1.01
Education
	Medium (vs Low)	0.72	0.41	−0.80	164.17	0.43	0.32	1.63
	High (vs Low)	0.33	0.57	−1.94	162.45	0.05	0.11	1.02
Nationality
	Turkish-Dutch (vs. Dutch)	1.09	0.86	0.10	168.51	0.92	0.20	5.90
	Marrocan-Dutch (vs. Dutch)	0.37	0.66	−1.53	167.74	0.13	0.10	1.34
	Antillian-Dutch (vs. Dutch)	1.22	0.71	0.28	168.50	0.78	0.30	4.93
	Surinam-Dutch (vs. Dutch)	0.99	0.89	−0.01	168.98	0.99	0.17	5.67
	Surinam (vs. Dutch)	1.54	0.86	0.50	168.70	0.62	0.28	8.39
	Other (vs. Dutch)	0.80	0.72	−0.32	153.16	0.75	0.19	3.33
	Other-Dutch (vs. Dutch)	0.95	0.91	−0.06	168.93	0.95	0.16	5.74
Pseudo R^2 =.06	(p = .24)

Summary of the logistic regression analysis, which assessed if TBI history predicts whether or not detainees had any jail sentences, controlling for background variables. Results show no significant effect on TBI history or any of the confounding variables. SE = standard error, df = degrees of freedom, p = p-value, CI = 95% confidence interval.