Study 1
Stein and colleagues (2003) conducted a randomized controlled study during the 2001–02 academic year to assess the effectiveness of Cognitive Behavioral Intervention for Trauma in Schools (CBITS) at two large middle schools in a primarily Latino community in East Los Angeles, Calif. Sixth-grade students were considered eligible to participate in the study if they had substantial exposure to violence, clinical levels of posttraumatic stress disorder (PTSD) symptoms, PTSD symptoms related to exposure to violence that they were willing to discuss in a group (as determined by their school-based mental health clinician), and if they did not appear too disruptive to participate in a group therapy intervention session (in the opinion of their school-based mental health clinician).
Eligible students were randomly assigned to a 10-session standardized cognitive–behavioral therapy. Students were randomly assigned to either the early-intervention group (n = 61) or to a waitlist delayed-intervention control group (n = 65). School officials preferred to provide an intervention program to all students, so students assigned to the waitlist delayed-intervention control group received CBITS 3 months after the early intervention group participated in the program. Therefore, at the 3-month follow-up, the early-intervention group was compared to the waitlist delayed-intervention comparison group before they participated in the intervention. However, at the 6-month follow-up, all study participants had received the CBITS program. Data from students was collected at baseline and at 3 months. Data was also collected at 6 months after the waitlist delayed-intervention control group had received 3 months of intervention. The CrimeSolutions review of this study focused on the comparison between the early-intervention group and the wait-list delayed-intervention control group at the 3-month follow up.
The early intervention group had an average age of 11 years and was 33 percent female. The group also had a Child PTSD Symptom Scale (CPSS) average score of 24.5 (indicating moderate to severe PTSD symptom levels). The waitlist delayed-intervention control group had an average age of 10.9 years, was 38 percent female, and had an average CPSS score of 23.5. There were no significant differences between the two groups on baseline characteristics.
Multiple measures were used to assess symptoms of PTSD, symptoms of depression, child psychological dysfunction, and classroom behavior. PTSD symptoms were assessed using the CPSS, a 17-item child self-report measure where students rate how often they are bothered by each symptom in the past month on a scale from 0 (not at all) to 3 (almost always). Depression was measured using the Child Depression Inventory (CDI), a 26-item scale that assesses children’s cognitive, affective, and behavioral symptoms of depression. Child psychosocial dysfunction was measured using the 35-item Pediatric Symptom Checklist (PSC), in which a student's parents rate the frequency of the student’s emotional and behavioral problem on a scale from 0 (never) to 2 (often). Classroom behavior was measured by having the student’s teacher complete the 6-item Teacher–Child Rating Scale for shyness/anxiousness, learning problems, and an acting out behavior problem subscales. The teachers rate how much of a problem each behavior is on a scale from 1 (not a problem) to 5 (very serious problem).
Linear regression to estimate the mean difference in outcome scores between the two intervention groups at 3 months and 6 months was used to assess the effectiveness of CBITS. Effect sizes were calculated as the ratio of the estimated treatment effect (early intervention score minus delayed intervention score at follow-up, after controlling for baseline scores) to the pooled standard deviation at baseline. No subgroup analysis was conducted.
Study 2
Kataoka and colleagues (2003) evaluated CBITS using a quasi-experimental design with recent immigrant Latino children to test the effectiveness of the Mental Health for Immigrants Program (MHIP) child intervention, which is an eight-session cognitive–behavioral therapy group program based on CBITS. Nine public schools in Los Angeles, Calif., agreed to participate in the study. A total of 970 students were eligible for screening (i.e., were in grades 3–8, were foreign born, had immigrated to the United States within the past 3 years, and spoke Spanish). Ninety-one percent of the sample (879 students) completed a screening questionnaire regarding exposure to violence and symptoms of trauma. Thirty-one percent of the screened students (276 children) reported clinical PTSD or depression symptoms (or both) and were recruited for the study. Of these, 83 percent (229 students) were given parental permission to participate. A total of 198 Spanish-speaking immigrant students in grades 3–8 were included in the final sample because they were available for the 3-month follow up.
Initially, 67 students were randomly assigned to receive the MHIP intervention immediately, and 46 students were assigned to a waitlist control group. Waitlist students were given referrals to community mental health agencies, though most subjects did not follow up on these referrals. Later in the school year, an additional 85 eligible students were assigned to the intervention (which introduced a nonrandomized group into the early intervention treatment group), resulting in a total of 152 children participating in the early MHIP intervention and the original 46 in the waitlist control group. The randomized and nonrandomized children did not differ on baseline violence exposure, symptom levels, or socioeconomic characteristics, except for a significant difference in parental education (which was higher in the nonrandomized group). Data on the 152 students receiving CBITS and the 46 waitlist control group students was used in the analyses.
The early intervention group was 51 percent female with an average age of 11.5 years. The waitlist control group was 47 percent female with an average age of 11.2 years. All study participants were Latino, with country of origin varying from Mexico (57 percent), El Salvador (18 percent), Guatemala (11 percent), and other countries (13 percent). There were no statistically significant differences in demographic characteristics between the two groups, except for parental education; the parents of the students in the waitlist group had significantly fewer years of education.
During the 3-month follow-up period, exposure to community violence was measured with a modified version of the Life Events Scale, a 34-item scale that asks about the frequency of several types of violence directed at the study participant or directly witnessed by them (such as threats, slapping/hitting/punching, knife attacks, and shootings) in multiple locations over the past year and throughout the participant's lifetime. Symptoms of PTSD reported in the past month were measured with the CPSS. The CDI was used to measure depressive symptoms reported in the past two weeks. All measures were translated from English to Spanish by the school district’s translation unit.
Comparison of continued data between baseline and follow-up was completed using a two-tailed Student t-test. Categorical data was compared using the chi-square statistic. In addition, linear regression was used to examine bivariate and multivariate relationships of outcome variables. To obtain robust estimates of the standard errors, adjustments for clustering were also made to account for the different assignment strategies. This could take into account potential school effects as well as any systematic differences in school demographics. No subgroup analysis was conducted.
