Looking Forward and Backward in Records for Risks among Homicidal Youth

Abstract

To identify risks for commission of homicide, 26 convicted Homicidal Youth (M age = 14.9 yr., SD = 1.4; n = 26; 1 girl, 25 boys) were matched with 26 Nonviolent Delinquents and 26 clinic-referred Controls. Youth were tracked backward 8 years (M = 7.7 yr., SD = 15) and forward 3 years (M = 3.1 yr., SD = 1.2) in records. Data analysis was Shao's bootstrapped logistic regression yielding area under the curve (AUC) and odds ratios (OR). Predictors of homicide were poorer executive function (OR = 7.04e+40), violent family (OR = 4.01e-16), and alcohol abuse (OR = 7.33e-17; AUC = .97, 95% CI = .77-.99). From earlier studies, 101 Homicidal Youth and their Controls were reanalyzed similarly. Predictors were poorer executive function (OR = 6.51), lower social maturity (OR = 0.28), weapon possession (OR = 26.10), and gang membership (OR = 4.14; AUC = .98, 95% CI = .96-.99). Groups were combined, i.e., 26 and 101 Homicidal; 127 Homicidal Youth (7 girls, 120 boys) and their matched Controls were tracked in records. The predictor was poorer executive function (OR = 3.34e-21; AUC = .98, 95% CI = .96-.97). When 127 Homicidal Youth were compared with 127 matched Nonviolent Delinquents, predictors were poorer executive function (OR = 2.83e-02), weapon possession (OR = 1.63e-10), lower social maturity (OR = 1.15), and use of special education services (OR = .94; AUC = .94, 95% CI = .37-.99).

An exploration of the current knowledge on young people who kill: A systematic review

“… Gender (male): Three cohort studies Hughes et al, 2009;Zagar et al, 2009a) and two case-control studies Zagar & Grove, 2010).…”

“… Gang/group membership: One cohort study (Zagar et al, 2009a) and three case-control studies Zagar et al, 1990;Zagar & Grove, 2010).…”

“…Four cohort studies were included in the review, all of which were carried out by Zagar and his colleagues Hughes et al, 2009;Zagar et al, 2009a;Zagar et al, 2009b). These studies used diverse, independent samples of randomly selected 'at risk' individuals in the USA.…”

Age effects on juvenile homicide perpetration

“…A comparison between homicidal juveniles and matched offending control groups conducted by Zagar, Busch, Grove, Hughes, and Arbit (2009) found arrests for homicide to be associated with a violent family history, alcohol abuse and neurological deficits/lower executive functioning. However, they were otherwise similar to their non-homicidal counterparts on many background factors.…”

Applying best treatments by using a regression equation to target violence-prone youth: a review1,2

“…Thus, the bootstrapped logistic regression represents a considerable improvement in predictive accuracy ( Zagar, Busch, Grove, & Hughes, 2009b ;Zagar & Grove, 2010 ), providing a sound empirical basis for risks that consistently and reliably predict future violent criminal activity. These risks include poor executive functioning (decision making and related abilities), lower social maturity, weapons possession conviction, violent family, gang membership or participation, male gender, academic underachievement, serious illnesses, prior court contact or arrest, low socioeconomic status, substance abuse, previous neurological disorder, alcohol abuse, head injury, and truancy/suspension or expulsion ( Table 1 ) Zagar, Arbit, Sylvies, Busch, & Hughes, 1990 ;Zagar, Arbit, Busch, Hughes, Schiliro, Sylvies, et al, 1992 ;Zagar, Arbit, Busch, Hughes, & Sylvies, 1998 ;Zagar, Busch, Grove, & Hughes, 2009b ;Zagar, Busch, Grove, Hughes, & Arbit, 2009 ;Zagar & Grove, 2010 ). When Chandler, Levitt, and List (2011) examined 12,989 higher-risk students among whom there were 500 perpetrators who committed shootings, the signifi cant personal characteristics predicting shooting were consistent with this prior research: male gender, academic underachievement, prior court contact or arrest, low in socioeconomic status (SES), truancy, suspension, and expulsion.…”