研究背景：儿童行为问题是一个全球性的公共健康问题，会对儿童、家庭和社会产生深远的负面影响。据美国疾病控制与预防中心估计，5名儿童中就有1名存在心理行为问题。《健康中国行动》明确提出，针对儿童常见的心理行为问题，要开展早期识别与干预研究，应用并推广效果显著的心理干预技术和方法。而父母作为主要照顾者，对孩子情绪和行为等方面的发展具有独特而重要的影响，通过父母干预以预防和治疗儿童的外化行为问题具有悠久历史。依托循证父母干预方案建立本土化的父母干预服务体系，能够为提升家庭教育指导的专业水平，预防和减少儿童外化行为问题的发生和发展提供有益参考，为儿童行为健康循证干预服务的实施提供实践经验。

研究目的：本研究围绕小学生外化行为问题及相关循证干预研究开展，整体可分为现状调研(研究一)和干预研究(研究二至研究五)两大部分。现状调研主要探究小学生外化行为问题的检出率、人口学分布特征及与相关家庭因素，在此基础上，干预研究采用儿童外化行为问题的循证干预方案——父母行为训练(Behavioral Parent Training，BPT)，通过随机对照试验考察BPT缓解儿童外化行为问题的有效性，并对其作用机制、干预效果发展轨迹和潜在影响因素及在小学环境中实施的可行性进行了分析。

研究方法：研究一在北京市、河南省安阳市和平顶山市宝丰县三个地区选取了9所项目小学，对每个学校1-6年级的学生进行整班抽取，最终将2145名家长纳入研究。干预研究在研究一中所调研的北京市某小学开展了平行、单盲的随机对照试验。依据纳入和排除标准，141名1-6年级儿童的父母纳入研究，经过随机分组，干预组父母 (n=71)接受了为期两个月的 BPT小组干预，而对照组 (n=69)父母在此期间接受由学校提供的家长课程等常规服务，两组父母均在测量团队的指导下完成了基线和后测两次测量。其中，研究二和研究三以群体为视角，评估了BPT小组干预对外化行为问题的有效性及其作用机制；研究四以个体为中心分析了干预效果的发展轨迹及潜在影响因素；研究五以整个干预方案的实施情况为视角，评估在小学学校环境下开展BPT 小组干预的可行性。在定量研究的基础上，研究还结合质性访谈结果对干预效果影响因素及在实施可行性进行了深入讨论。关于干预效果的数据分析采用意向性分析原则(ITT)与遵循研究方案分析方法(PP)相结合的方式进行。本研究通过了中国临床试验注册伦理委员会的审查(ChiECRCT-20180175)。

研究结果：

现状调查研究数据的分析结果表明：

1.小学生外化行为问题检出率为15.94%，注意缺陷多动冲动障碍、对立违抗障碍及品行障碍的检出率分别为6.12%、5.81%和0.97%。

2.男孩外化行为问题严重程度显著高于女孩；儿童年龄段越小，外化行为问题严重程度及检出率均越高；家庭年收入为一般水平的儿童外化行为问题严重程度和检出率均显著高于其他儿童。

3.教养方式与外化行为问题以及注意缺陷症状、多动冲动症状和对立违抗症状三项具体症状均显著负相关，教养压力与外化行为问题及这三项症状均显著正相关。

随机对照试验干预研究的结果表明：

1. BPT小组干预能够有效缓解儿童外化行为问题

(1)ITT分析结果表明:干预组在外化行为问题(P=0.043)和其他不良行为维度(P=0.042)后测得分显著低于对照组。PP分析结果显示：干预组在外化行为问题(P=0.015)及注意缺陷多动症状(P=0.043)、对立违抗症状(P=0.040)、其他不良行为(P=0.008)3个症状维度的后测得分均显著低于对照组。

(2)BPT小组对低年龄段儿童外化行为问题的干预效果显著大于高年龄段。

2. BPT小组干预能有效改善父母教养方式、缓解父母教养压力

ITT分析结果和PP分析结果一致表明:干预组教养方式后测得分显著高于对照组(ITT分析:P=0.003; PP分析:P=0.005)、教养压力后测得分显著低于对照组(ITT分析:P=0.013; PP分析:P=0.013)，两组父母情绪调节后测得分无显著差异。

3. BPT小组干预缓解儿童外化行为问题的作用机制

(1)教养方式的中介作用显著。BPT小组能够通过提升父母教养方式进而缓解儿童外化行为问题。

(2)教养方式和教养压力的链式中介作用显著。BPT小组的能够通过改善父母的教养方式进而降低父母的教养压力以缓解儿童外化行为问题。这两项间接效应分别占儿童外化行为问题总效应比重的36.48%和12.26%，共占据48.74%。

(3)教养压力的中介作用不显著。

4.BPT干预前后干预组儿童的外化行为问题呈现出四类发展轨迹

按照干预组儿童外化行为问题随时间变化的不同发展轨迹，可以将干预组儿童分成 4 个亚组, 别命名为“高分快速缓解组”，“低分缓解组”，“高分缓慢缓解组”以及“轻度恶化组”。

5.儿童外化行为问题干预反应不同发展轨迹的影响因素

通过质性访谈与定量分析相结合的混合研究方法，发现相比较“高分缓慢缓解组”和“轻度恶化组”，父母参与小组的次数和对实践应用情况可能是“高分快速缓解组”和“低分缓解组”的保护因素。

6. 在小学环境中开展BPT小组干预具有良好的可行性

 (1)干预组父母小组出勤率较高，小组课程的平均出勤率为75%，平均每位家长参与了约6次(共8次课)。

(2)干预组父母对满意度量表5个维度的评分均较在9分以上(共10分)。

(3)通过对服务递送者和校长、老师的访谈中发现BPT小组的内容、形式、教材教具、与家长/校方需求匹配度等方面在实施过程中均具备一定的优势。

研究结论：

(1)小学生外化行为问题检出率为15.94%，男孩、低年龄段、独生子女以及家庭年收入为一般水平可能是小学生外化行为问题在人口学层面的风险因素。

(2)BPT小组干预是预防和缓解儿童外化行为问题的有效干预方案。

(3)父母教养方式的改善和教养压力的降低在BPT干预方案缓解儿童外化行为问题的过程中发挥了重要作用。

(4)良好的课程参与度和课后积极的实践应用情况可能会促进干预反应效果。

(5)在小学环境中实施BPT小组干预方案是可行的。

Background: Problem behavior in children is a global public health issue that has profound negative impacts on children, families, and society. According to the Centers for Disease Control and Prevention (CDC) in the United States, approximately 1 in 5 children has psychological and problem behavior. The Healthy China Action explicitly states the need for early identification and intervention research for common psychological and behavioral problems in children and adolescents, as well as the promotion and application of effective psychological intervention techniques. As primary caregivers, parents have a unique and significant influence on the emotional and behavioral development of their children, and the use of parental intervention to prevent and treat externalizing problem behavior in children has a long history. Establishing a localized parental intervention service system based on evidence-based parental intervention programs can provide useful references for improving the professional level of family education guidance, preventing and reducing the occurrence and development of externalized behavioral problems in children, and providing practical experience for the implementation of evidence-based intervention services for children's behavioral health.

Objective: This study focuses on the externalizing behavior problems of primary school students and related evidence-based intervention research. It can be divided into two parts: the survey of present situation (Study 1) and the intervention study (Studies 2-5). The survey focuses on externalizing problem behavior in elementary school students, exploring the detection rate, demographic distribution characteristics, and the relevant family factors. Based on this, the intervention study adopt an evidence-based intervention program for externalizing problem Behavior elementary school students—Behavioral Parent Training (BPT). The effectiveness of BPT in alleviating externalizing problem Behavior in children is investigated through a randomized controlled trial. The study also analyzes the mechanisms, developmental trajectories of intervention effects, potential influencing factors, and feasibility of implementing BPT in elementary school.

Methods: In Study 1, 9 primary schools in Beijing, Anyang City and Baofeng County in Pingdingshan City in Henan Province were selected. Students from grades 1 to 6 were selected from each school, resulting in a total of 2,145 parents included in the study. In the intervention study, a parallel, single-blind randomized controlled trial was conducted in a primary school in Beijing，which was investigated in Study 1. Based on the inclusion and exclusion criteria, 141 parents of children in grades 1 to 6 were selected in the study. They were randomly assigned to either the intervention group (n=71), which received a two-month group-based Behavioral Parent Training (BPT) intervention, or the control group (n=69), which received routine services such as parent courses provided by the school. Both groups of parents completed baseline and post-test measurements under the guidance of the measurement team. Study 2 and Study 3 evaluated the effectiveness and mechanism of BPT intervention from a group perspective. Study 4 analyzed developmental trajectories and potential influencing factors of intervention effects from an individual-centered perspective. Study 5 evaluated the feasibility of implementing BPT intervention in primary school from the perspective of the implementation of the entire intervention program. In addition to quantitative research, the study conducted in-depth discussions on the influencing factors of intervention effects and the feasibility of implementation. Data analysis on intervention effects was conducted using the Intent To Treat (ITT) principle combined with the Per-protocol analysis (PP) method. This study has been reviewed and approved by the Chinese Clinical Trial Registry Ethics Committee (ChiECRCT-20180175).

Results: The data analysis results of the survey showed:

1. The detection rate of externalizing problem behavior in elementary school students was 15.94%. The detection rates for Attention Deficit and Hyperactivity Disorder (ADHD), Oppositional Defiant Disorder (ODD), and Conduct Disorder (CD) were 6.12%, 5.81%, and 0.97%, respectively.

2. Boys had significantly higher severity of externalizing problem behavior than girls. The severity and detection rate of externalizing problem behavior were higher in younger children. Moderate family income level wad significantly associated with higher severity and detection rate of externalizing problem behavior in children.

3. Parenting style was negatively correlated with externalizing problem behavior, as well as symptoms of Attention Deficit, Hyperactivity and Oppositional Defiance. Parenting stress was positively correlated with externalizing problem behavior and these three symptom categories.

The results of the intervention study through the randomized controlled trial showed:

1. The BPT group intervention was effective in reducing children's externalizing problem behavior.

(1) ITT analysis showed that the intervention group had significantly lower post-test scores than the control group in externalizing problem behavior (P=0.043) and the Unnamed Factor (P=0.042). PP analysis showed that the intervention group had significantly lower post-test scores than the control group in externalizing problem behavior (P=0.015), as well as symptoms of Attention Deficit Hyperactivity Disorder Behavior (P=0.043), Oppositional Defiant Behavior (P=0.040), and Unnamed Factor (P=0.008).

(2) The intervention effect of the BPT group was significantly greater for younger children of externalizing problem behavior than those older children

2. The BPT group intervention effectively improved parenting style and reduced parenting stress.

ITT analysis and PP analysis consistently showed that the intervention group had significantly higher post-test scores in Parenting style (ITT analysis: P=0.003; PP analysis: P=0.005) and significantly lower post-test scores in parenting stress (ITT analysis: P=0.013; PP analysis: P=0.013) compared to the control group. There was no significant difference between the two groups in post-test scores of parental emotional regulation.

3. The mechanisms of the BPT group intervention in alleviating children's externalizing problem behavior.

(1) Parenting style played a significant mediating role. The BPT group intervention improved Parenting style, leading to a reduction in children's externalizing problem behavior.

(2) There was a significant chain mediation effect of Parenting style and parenting stress. The BPT group intervention improved Parenting style, which in turn reduced parenting stress and alleviated children's externalizing problem behavior. These two indirect effects accounted for 36.48% and 12.26% of the total effect on children's externalizing problem behavior, respectively, totaling 48.74%.

(3) The mediating effect of parenting stress was not significant.

4. The BPT intervention resulted in four different developmental trajectories of children's externalizing problem behavior.

Based on the different developmental trajectories of children's externalizing problem behavior over time, the intervention group was divided into four subgroups: "high score-high response group", "low score-low response group", "high score-low response group", and "mild deterioration group".

5. Factors influencing the intervention response of different developmental trajectories of children's externalizing problem behavior.

Through a mixed research method combining quantitative data and qualitative interviews, it was found that compared to the "high score-low response group" and "mild deterioration group," the frequency of parents' participation in the group and their application of the intervention techniques may serve as protective factors for the "high score-high response group" and "low score-low response group."

6. The implementation of the BPT group intervention in primary schools was feasible.

(1) The attendance rate of parents in the intervention group was high, with an average attendance rate of 75% for group sessions, and each parent participated in approximately 6 out of 8 sessions.

(2) The satisfaction ratings of the intervention group parents on the satisfaction scale were above 9 out of 10.

(3) Interviews with service providers, principals, and teachers revealed advantages of the BPT group intervention in terms of content, format, teaching materials, and alignment with the needs of parents and schools

Conclusions:

(1) The detection rate of externalizing problem behavior in elementary school students is 15.94%. Being a boy, belonging to a younger age group, being an only child, and having a moderate family income level may be demographic risk factors for externalizing problem behavior in elementary school students.

(2) BPT group intervention is an effective intervention program for preventing and alleviating children's externalizing problem behavior.

(3) During the intervention process, improvements in Parenting style and reductions in parenting stress play important roles in alleviating children's externalizing problem behavior.

(4) Active participation in the program and positive application of learned techniques after the intervention may enhance the intervention response.

(5) Implementing the BPT group intervention program in primary school settings is feasible.