Research participants

This research was approved by the Institutional Review Board of Chang Gung Memorial Hospital (IRB102-0771A3). The judges of Taiwan’s Kaohsiung Juvenile and Family Court required underage individuals that have been arrested for substance use to participate in the treatment program in Kaohsiung Chang Gung Memorial Hospital. In total, 103 young participants who attended treatment at the hospital and their primary caregivers were recruited consecutively between July 2011 and December 2013. The inclusion criteria were as follows: (1) aged between 12 and 18 years old; (2) having illicit drug use; and (3) at least one of their caregivers could attend the treatment program. The exclusion criteria included (1) intellectual disability, (2) having apparent psychotic symptoms, and (3) having first-class illicit drug use (i.e., heroin, morphine, or cocaine).

During this research, the 103 patients were ordered to attend 10 sessions of weekly out-patient drug abuse treatment program while their caregivers were required to participate in 10 sessions of weekly parenting-skill training program. Both programs were held at the Kaohsiung Chang Gung Memorial Hospital. Before taking part in this research, each participant submitted a signed written informed consent, while the researchers emphasized whether to take part in this research or not would never affect his or her legal status and that all personal information provided would be kept strictly confidential. Details of treatment protocols and research procedures have been demonstrated elsewhere [16, 17].

Motivational enhancement psychotherapy program for young people

Young participants received 10 treatment sessions on a weekly basis. Led by two experienced psychologists from the hospital, the group relapse prevention program, which was basically constituted of motivational enhancement ideas, accommodated about eight participants in each session lasting 120 min with a 10-min break. The aim of such a group counseling meeting was to evoke the young participants’ motivations for a change by identifying the causes for their drug addiction, the reasons for their abstinence from substance abuse, their concerns about substance use and their perception of illicit drugs in their current and long-term lives. Having developed a rapport with the participants, the psychologists were able to learn how illicit drugs fitted into their lives. Feedback was the main counseling technique used during the meeting, in which the psychologists asked questions and the participants reflected their past in the hope to prompt the latter’s self-motivational statements [18]. The focus of the treatment program was to identify the situations which had put the young participants at high risk for drug abuse, to enhance their motivation to abstain from substance abuse and to develop coping strategies to prevent relapse.

Parenting skills training program for caregivers

The parenting skills training program also included 10 weekly 120-min sessions, conducted by two senior counseling psychologists or social workers appointed by the court. The therapists first shared common legal knowledge to alleviate the concerns and helplessness of the caregivers and then handled their emotional reactions to their teens, such as shock, anger and frustration. Helping the caregivers check out their current relationships and their communication skills with their teenagers, the therapists were able to guide the caregivers to judge how negative their family relationships were and how they could change their own behaviors and attitudes so as to improve their daily home environment and atmosphere. Not only did the therapists provide the caregivers with new ways to engage with their adolescents, but they also taught the caregivers how to solve such issues as their adolescents separating from them in a non-normative manner [19]. The purpose of this training program was to teach those caregivers more effective skills to deal with the drug abuse problems caused by their youths.

Research procedures and measures

Figure 1 illustrates the main points of therapy and flowchart of research procedures. At the beginning of the treatment courses, the information on sociodemographic characteristics of participating patients (e.g., categories of substances being used, history of previous convictions, family status, and academic or social status) was provided by Taiwan’s Kaohsiung Juvenile and Family Court. The young patients were asked to fill out the Chinese Craving Beliefs Questionnaire (CCBQ), the Adolescents’ Behavior-problem Scale (ABS) and the Family APGAR at both the first and last treatment sessions (10 weeks later). The patients’ caregivers were required to complete the Family APGAR, the 12-item version of the Chinese health questionnaire (CHQ-12) and the Chinese version of the Parenting Stress Index (PSI) at the first session and the last session of treatment as well.

The CCBQ was adapted from a craving beliefs questionnaire (CBQ) developed by Wright [20]. This questionnaire, consisting of 10 items, measures beliefs and understandings of substance cravings and is answered with a 4-point Likert scale (from total disagreement (1) to total agreement (4)). The higher the total score, the higher the substance craving. With acceptable reliability and effectiveness, the CCBQ is suitable as a research tool for assessing the substance craving beliefs [21].

The ABS is a self-administered questionnaire used to measure the emotional disturbance of the young patients. The ABS consists of 50 items, all of which are answered with a 6-point Likert scale. Divided into five categories, namely self-awareness, physical and mental development, school life, interpersonal relationships and family life, the ABS can be used to give a composite score and has good reliability and validity as a questionnaire [22].

Family APGAR has been widely used to measure family’s well-being [23]. It involves the following five items: degree of adaptation, partnership, growth, affection and resolution in the family. Each item is answered using a 3-point Likert scale ranging from 0 (low satisfaction) to 2 (high satisfaction). The total score ranges from 0 to 10. The higher the score, the better the family function. The Chinese version of the questionnaire has sufficient internal reliability and validity [24].

The CHQ-12, a 12-item self-reporting questionnaire, is a modified version of the General Health Questionnaire [25]. This tool has been widely used in research to identify subjects in primary care and those in a community setting who have minor psychiatric disorders. A 4-point Likert scale (0 = not at all, to 3 = more than usual) is provided as a response format to analyze the conditions during the preceding 2 weeks (score range = 12–36). The higher the score, the worse the health condition. The questionnaire has good reliability and validity [26].

The PSI is a standardized Chinese version of the original 120-item questionnaire used to measure the elements of parental function [27]. The PSI Parent Domain Scale contains 54 items and consists of seven subscales. The PSI Child Domain Scale contains 47 items and has six subscales. The parent and child domains are added together to get a total score and a derived raw-to-percentile score. The patients’ caregivers rated their level of agreement with these items on a 5-point Likert scale. The higher the score, the greater the level of parenting stress [28].

Follow-up for substance-use relapse

Upon completing the treatment courses, all the participants were reverted to court supervision and probation again, including notifying the protection officers of their academic, social, and living status about once every month. During the follow-up period, the patients were required to provide urine samples, which the judges or protection officers would test to decide at their own discretion whether or not drug residues were present. If a test result was positive, the court would give the youth in question a hearing and then sentence him or her to take reformatory education or to be confined in the detoxification unit of the detention center. The outcome of this research was concerned with substance-use relapse during a 5-year follow-up period.

Statistical analysis

We analyzed the data in this study using the statistical software package SPSS, version 21.0 (SPSS Inc., Chicago, IL, USA). Variables are presented as either mean ± standard deviation (SD) or frequency. Paired-t test was adopted to examine any changes in the measures for either the patients or their caregivers throughout the 10-week treatment program. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used to evaluate whether the treatment effectiveness served as predictors of patients’ relapse during the 5-year follow-up period.

The completion date of the family-oriented program was set as the index date and was used to calculate risk over time. As for survival analysis, the time function was defined as the number of days from the index date to the end of the period for those patients who had no other instance of substance use to that point or to the date of relapse if such relapse occurred before the end of the follow-up period. We controlled for socio-demographic variables to develop a Cox regression model to estimate the treatment effects on relapse. Adjusted hazard ratios (aHR) were calculated with 95% confidence intervals (CI). We considered a two-tailed p-value less than 0.05 statistically significant.