A Paradigm Shift in Intervention Approaches for Children with Attention-Deficits/Hyperactivity Disorders: A Systematic Review of Psycho-Behavioral Interventions

Objectives: This systematic review examines the literature of psycho-behavioural interventions for individuals diagnosed with AD/HD between 2005 and 2015 in order to answer the following research questions: (1) What are the underlying theoretical perspectives of AD/HD in the intervention design? (2) What are the measures used to assess the various AD/HD interventional approaches? (3) How effective are the identified AD/HD interventions? Method: 18 studies involving approximately 1200 participants met the selection criteria under the psycho-behavioural framework and went through the systematic review procedures. Results: Three approaches to intervention are identified, namely, ability-specific training focusing on enhancing working memory and attention, skills-building intervention aiming at improving organizational and social skills, and, interaction oriented programs targeting at mediating relationships between parents and their children. The interaction-oriented interventions tend to demonstrate the highest efficacy in improving the psycho-behavioural performance of individuals with AD/ HD. Conclusion: Different intervention approaches are founded on different underlying theoretical perspectives of the psycho-behavioural performance in AD/HD. There has been a paradigm shift from the management of dysfunction to the acquisition of functions based on the behavioural management theories and pharmaceutical knowledge-base to those of an ability-specific approach and skill-building approach to interventions for individuals with AD/HD with the dominance of the theory of executive functioning in the last decades. It is speculated that the trend of AD/HD intervention will continue to shift from that of a uni-directional childcentred approach to those of a multi-directional ecological systems perspective. This implication calls for more efforts in developing valid assessment measures to evaluate the new constructs assessing the inter-personal relationships within the AD/HD individual's ecological systems.

Referral for AD/HD intervention has been constantly arising since the 1990s. Prevalence rates for children diagnosed with AD/HD have reportedly been as high as 11% since the last decade [6] with inclusion of comorbidity statistics. In the recent decade, the pure prevalence rate has been reported as high as 9% of school-age children [7]. Various intervention programs and related assessment measures were developed. This has triggered basic research studies targeting this population and various theories attempting to account for the disorders have emerged. Consequently, their findings have in turn informed the service providers and subsequently formed various theoretical frameworks for intervention practices.
The pharmaceutical approach of medication and the behavioral management approach have dominated the field of AD/HD intervention since the 1900's. For example, behavioral parent training (BPT) for AD/HD demonstrated reduction in AD/HD symptoms and associated oppositional problematic behaviors [8][9][10]. Parental competence as well as stress reduction was also found to be improved. Moreover, classroom behavior contingency management in school yielded improvements in teacher-reports of student's functioning [11]. On the other hand, stimulant medication studies demonstrated reduction in core AD/HD symptoms such as non-compliance and aggression, and improvements in academic productivity [12,13]. Effect-size calculations from both behavioral management interventions and stimulant medication studies showed substantial improvements across many domains of functioning [14].
Despite the significant intervention effects found in stimulant medication, parents chose not to use stimulant medication because of its notable side-effects [15][16][17]. It was found that more than 50% of children prescribed stimulant medication stopped their medication intake within a school year and it was estimated that fewer than 10% of children with AD/HD continued their medication into long-term [18,19]. Behavioral management interventions, on the other hand, were found to be less effective in the carry-over of trained behaviors to other persons, other settings and other behavior requirements. Many continued to exhibit associated difficulties such as impulsivity and poor peer relationships [20,21]. Moreover, their short-lasting treatment effects further suggest that these approaches temporarily control their behavioral difficulties which resurface once treatment is terminated.
Thus, although the acute treatment benefits of both the behavioral management approach and pharmaceutical approaches to AD/HD interventions in the 1900's are well-documented in the literature, their limitations, such as the lack of normalization of functioning for many children following treatment, lack of generalization effects into non-intervention settings, resistance to long-term commitment, and lack of effectiveness in long-term functioning after termination of these interventions, have demanded further exploration of other intervention modalities. Instead of tapping into the surface behavioral issues of AD/HD symptoms, more penetrating approaches to interventions that can address the underlying deficits for individuals with AD/HD are warranted.

Aim of Study
Adopting a critical appraisal process of systematic review, this study examines the burgeoning literature related to AD/HD intervention studies on the underlying theoretical perspectives of AD/HD along with evidence-based assessment measures evaluating the functioning and behavioral performance of the AD/ HD stakeholders during the period of 2005-2015. The following research questions have prompted this systematic review study: (1) What are the underlying theoretical perspectives of AD/HD in the intervention design? (2) What are the measures used to assess the various AD/HD interventional approaches? (3) How effective are the identified AD/HD interventions?

Literature Review
The theoretical framework of executive functioning Towards the era of 2000s, Barkley proposed the theoretical framework of executive functioning which posits that AD/HD is a deficit in behavioral inhibition in four executive functions: (a) working memory, (b) self-regulation of affect and motivation, (c) internalization of speech, and (d) behavioral analysis and synthesis [4,22]. Barkley's theory provides one of the first testable theories of AD/HD. Thereafter, various research studies focusing on different aspects of executive functioning emerged. As a result, the identification and assessment of the psychobehavioural problems for individuals with AD/HD has become more specific. Consequently, various intervention programs focusing on improving specific modalities of the many executive functioning problems have developed, such as working memory, inhibitory control, organization skills, empathic functioning and emotional regulation.
The model of inhibition: Since inhibition was proposed as the primary executive deficit in AD/HD [22], research have been focusing on investigating inhibition using motor inhibitory measures, such as the Go/No-go task and Stop task [23,24]. However, the validity of using these tasks to actually measuring inhibition is being questioned because these tasks failed to control for potential confounding elements such as more rudimentary cognitive or physiologic processes [25]. Instead, it was found that the Stop task generally measures stimulus anticipation, response preparation, visual processing and the ability to sustain the intentional act [26], each of these processes an individual with AD/HD is found to have impairment [27,28]. For example, Van der Meer's study did not find significant differences in inhibitory control or cognitive flexibility between AD/HD and control groups, suggesting that these two criteria may not be reliable differential constructs to make between-group discrimination. However, Van der Meer's team [29], when comparing the AD/HD group and the Autism Spectrum Disorders (ASD) group found that individuals with AD/HD showed more pronounced working memory deficits, oppositional symptoms and inattentiveness when compared to those with ASD who were found to manifest more detail-focused cognitive processing style and more impaired social cognitive skills. Thus, although inhibition was seen as an overarching determinant of AD/HD behavioral characteristics, the lack of The model of empathic functioning: In another study [32], it was found that inhibition is highly correlated to empathic functioning. Individuals with poor inhibitory control were found to be driven more by immediate stimuli than by long-term behavioral consequences. Their emotion-driven act often makes them careless and disorganized, and they show less empathy towards others' feelings. In contrast, individuals with good inhibitory control generally were led by long-term consequences of their behavior, are compliant to social conventions and are highly organized and disciplined. In fact, studies on empathic functioning have started since the late 1900s. For example, Feshbach's study [33] integrates both the affective and cognitive dimension and states that an empathic response constitutes: (a) the ability to identify and discriminate the emotional states of another, (b) the cognitive capacity to take the perspective or role of the other, and (c) the evocation of a shared affective response [34]. More updated research studies have been conducted to investigate the role of empathic functioning in individuals with AD/HD since the 2000s [35]. Their findings showed that individuals with AD/HD are having more difficulties specifically in the affective aspect of empathic functioning, as compared to those with comorbid ASD, who are found to have primarily deficits in the cognitive aspect.

The model of emotion regulation:
The recognition of the important role of the affective aspect of empathic functioning has led to the rise in research studies on emotion regulation in the recent decade. Emotion regulation is the ability to respond to the ever-changing demands of everyday experience with a range of emotions in a manner that is socially tolerable and sufficiently flexible as needed [36,37]. This functional perspective emphasizes the following dimensions of emotion regulation: (a) awareness of emotions, (b) acceptance of emotions, (c) ability to refrain from impulsive behaviors even when experiencing negative emotions, and (d) ability to employ emotion regulation strategies flexibly in appropriate situations to modulate emotional responses [38,39]. Studies of emotion regulation found that parenting behaviors and parent-child interactions jointly predict children's social functioning [40]. Positive parenting behaviors, such as limitsetting, parental warmth, and parenting styles have profound impact on children's socio-emotional functioning. Among individuals with AD/HD, parenting behaviors and the quality of parents' own emotion regulation abilities predict peer preference and antisocial behavior [41,42]. Therefore, AD/HD interventions should go beyond the individual with AD/HD and into those subsystems around the individual. In particular, family intervention is deeming important.

Search strategy
Studies were retrieved from publications in peer-reviewed journals from 2005 to 2015. We searched for studies in the English language in the following databases: Academic Search Premier, ERIC, ProQuest, PsycINFO and Scopus. The following keywords were used for all searches: 'AD/HD' or 'attention deficit and hyperactivity disorder', AND 'intervention' or 'training'; AND 'RCT' or 'controlled', NOT 'pharmacological' or 'medicines'. Two reviewers independently evaluated the titles and abstracts of the located studies to determine the eligibility for inclusion in this systematic review.

Selection criterion
The inclusion selection criteria were shown below: a) published trials so as to ensure a level of methodological adequacy and rigor among included trials and to avoid the inevitable problems with securing access to a full set of unpublished trials; b) studies that had adopted randomized controlled trials and/or controlled trial; c) treatment studies that focused children having a diagnosis of AD/HD and employed a non-pharmacological intervention; d) studies that contained information necessary to calculate the effect size statistic (i.e., pre-and post-means and standard deviations for the treatment condition). Those studies which involve single-subject designs, case studies, and unpublished studies and interventions were excluded in this review.

Intervention effectiveness analysis
We estimated the difference between intervention and comparison conditions for each study by calculating the standardized mean difference (SMD), the calculated scores of effect size (ES), can be compared across different measures/ studies. Its estimate was calculated from the post-treatment scores and standard deviations provided in each study report. We chose the SMD over the weighted mean difference because multiple measures with different scales were used to assess the outcomes of psycho-behavioral interventions. ES from each study was calculated using the equation below: where is the mean of treatment group, is the mean of control group, is the sample size of the treatment group, is the sample size of the control group, is the variance of the treatment group, and is the variance of the control group. In each study, individual ES was calculated assisted by the Comprehensive meta-analysis version 2.2.064 (www.metaanalysis.com).

Study identification
Following a standardized systematic review procedure, with two reviewers appraised the selected studies concurrently but independently, 410 studies were located in the search. 18 studies involving approximately 1200 participants met the selection criteria and were included in the analyses. Altogether 392 studies were removed from our systematic review study for the following reasons: 1) Single subject studies were not included in this systematic review. 2) Some studies were excluded because they did not provide enough information, such as control group data or baseline measures and therefore did not allow us to proceed with the calculation required in the systematic review. 3) Other studies only compared the AD/HD and non-AD/HD characteristics without stating intervention details and we therefore could not categorize the types of interventions. 4) For those studies which provided the necessary data for the systematic review but did not fulfill the inclusion criteria, such as written in a non-English language or published as conference papers but not academic journals, they were also excluded in our systematic review. The flow chart of evidence search and selection was shown in Figure 1.

Summary characteristics of the 18 intervention studies in the systematic review
From the target variables the study aimed to assess by their selections of measures, the 18 studies were further categorized into three approaches to intervention, namely, abilityspecific interventions, skill-building and interaction-oriented interventions. The study features of each intervention program are listed (Table 1). Using the aforementioned intervention effective analysis, the effect size of each study was also reported. To obtain an overall average effect size (ES), individual ES from each study was calculated and reported in corresponding figures to depict graphically with confidence intervals (Figure 2). ES were combined to produce three overall ES for each intervention approach.

Ability-specific interventions
The ability-specific approach targets at improving visuospatial working memory, verbal working memory, motor response inhibition and nonverbal reasoning. A total of five studies (#3, #4, #7, #8 and #10) were included in the effect size calculations. Altogether, the five studies involved 257 subjects (120 treatment, 137 control) comparing working memory interventions with control or waitlist. As shown in Figure 3, all the ability-specific  Objectives: -to examine the extent to which working memory training in children with ADHD would diminish a core dysfunctional behavior associated with the disorder, "offtask" behavior during academic task performance; -to investigate the effect of computerized WM training.
Design: -double blinded RCT study on 90 trials of WM tasks daily for 25 days performed at home and supervised by parents; -assessments occurred at 1 week prior to the study, weekly throughout the duration of the study, 3 weeks after completion of the study; -max 40 min to complete the training session daily.
-WM training led to significant reduction in off-task ADHDassociated behavior on the RAST system and improvement on WM test; -No significantdifferences in either baseline levels or changes as a result of training for both outof-seat and vocalizes behaviors; -No significant differences between groups in improvement on parent rating scales; -Findings lend insight into the generalizability of the effects of WM training and the relation between deficits in WM and off-task behavioral components of ADHD.

Working Memory performance (WMI from WISC-IV)
Behaviour performance: -off-task behaviors such as off-task, out-of-seat, fidgets, vocalizes, and plays with object (RAST score); -questionnaires rated by teacher and parent.

Inter-rater reliability :
Off-task: 95%; Plays with object: 100%; Design: -blinded RCT study performed at home or school; -90 trials of WM tasks daily for 25 days; -delivered either at home or at school by psychologist, parent, or teacher; -the post intervention visit (T2) took place 5 to 6 weeks after the baseline visit, and the follow-up assessment; (T3) was done 3 months after T2; -40 min training time on every 1-2 days for 25 days.
-For the span-board task, there was a significant treatment effect both in post intervention and at follow-up; -Significant treatment effect for all executive tasks (visuospatial WM, verbal WM, response inhibition, nonverbal reasoning ability, and motor activity); -No significant treatment interaction for any variable between baseline-score and ADHD-subtype; -Parent ratings showed significant reduction in symptoms of inattention and hyperactivity/ impulsivity, both postintervention and at follow-up.

Nonverbal reasoning ability: (RCPM)
Motor activity: -number of head movements (Infrared camera) Behaviour performance: -inattention (ASR) -hyperactivity-Impulsivity (ASR) -rated by parents and teachers Not reported  Design: -blinded RCT study on total 14 sessions for parents, 120 min weekly session for 14 weeks performed at the university community department or mental health center; -deliver intervention to groups of 9-12 parents; -multi-informants and multimeasures of child and parenting behaviors were taken before and after the 14 week intervention.

Skill-building approach to intervention
-  Design: -blinded RCT study on a 10 to 13 week treatment period integrated across home and school; -included immediately following treatment, laboratory visits were scheduled with families and rating scales were sent to teachers; -5 to 7 months post-treatment by new teacher fill in rating scales; -CLAS: focus on parenting skills, child skills and classroom challenge with parents and children with ten 90 min child group meeting at clinic offices/school/over the phone; -PFT: focus only on parenting skills for parent with ten 90 min parent group meetings, plus up to six 30 min family meetings at clinic/ offices/school/over the phone; -TAU: no specific treatment recommendations and only provide two-session parenting workshop on the strategies taught in the CLAS groups.
-CLAS resulted in greater improvements in teacher-reported inattention, organizational skills, social skills, and global functioning relative to both PFT and TAU at post treatment; -Parents of children in CLAS reported greater improvement in organizational skills than PFT and greater improvements on all outcomes relative to TAU at posttreatment; -Differences between CLAS and TAU were maintained at followup for most parentreported measures but were not significant for teacher reported outcomes.
Organization skills: -organizational skills; management of materials/ supplies, task planning skills (COSS Parents and teachers).

Design:
-up to six 30 min meetings with teacher at school for 12 weeks; -included teacher consultation, parent training and child skills training; -using school-home report card; -compared groups posttreatment and at 3 to 5 month follow-up on parent and teacher ratings of inattention, sluggish cognitive tempo, and functional impairment.
-Children randomized to the Child Life and Attention Skills Program were reported to have significantly fewer inattention and sluggish cognitive tempo symptoms -Significantly improved social and organizational skills, relative to the control group.
-Gains were maintained at follow-up.

DSM-IV Inattention symptoms (CSI) Sluggish Cognitive Tempo Symptoms (SCT)
Functional Impairment: -social impairment (SSRS); -organization skills (COSS by Parents and teachers); -life skill knowledge (CLAS). -significant and moderate-to-large postintervention effects on school-based measures of ADHD and disruptive behavior symptoms, social functioning, and academic functioning.

Consumer Satisfaction
-Nonsignificant and less robust intervention effects on the homebased assessments of problem behaviors and social skills. -Both groups showed improvements over time on all measures. BPT+RCC was superior to RCC alone in reducing behavioral (p=0.017) and internalizing (p=0.042) problems.

School-Based
-No outcome differences were found in ADHD symptoms (p=0.161) and parenting stress (p=0.643).
-These results were equal for children with and without medication.
-Children allocated to RCC alone received more polypharmaceutical treatment.

Design:
-blinded RCT study on 12 week training program and weekly 2 h behavioral parent session for 8 week; -assessments occurred immediately preceding treatment, immediately after the 8 week treatment, 1 month follow-up evaluation; -audiotaped all sessions.
-Fathers in the COACHES group reduced their rates of negative talk and increased rates of praise as measured in parent-child observations. -Father ratings of the intensity of problem behaviors were reduced, relative to the waitlist condition.
-Groups did not differ on observations of use of commands or father ratings of child behavior problems.
-Untreated mothers did not significantly improve on observational measures or behavioral ratings.

Satisfaction with intervention (TAI)
Inter-rater reliability: Objectives: -to evaluate the efficacy of a psychoeducation programme for parents of children and adolescents with ADHD Participants: -81 children/adolescents (aged 5-18) with diagnosis of ADHD; -Well-structured psychoeducation programme (intervention group, n=44); -Parent counselling and support intervention (control group, n=37).

Design:
-blinded RCT study on five successive groups of 8-10 families who received 12 week 90 min weekly sessions; -taken before and after intervention and after a year follow-up ; -computerized program.
-Compared to the support control group, the psychoeducation group showed ADHD Index and cognitive/ inattention levels significantly reduced after the intervention ended.
-An improvement in the pro-social domain was also observed after 1 year follow-up.
-Clinical global impression found a statistically significant effect for severity over the time.
-Differences were initially found for the impact of the disorder in the family in different domains, including emotional and social functioning; these differences were no longer significant after alpha correction.
-No significant differences in quality of life or family stress were found in comparison with the control group.  Design: -RCT study on 14 week parenting program; -Five groups were co-led by staff; clinicians, six of whom were clinical psychology -complete questionnaires during group pretest session; -post-test sessions conducted 1 week after the 14 the session; -teaching parenting strategies.
-Compared to WL mothers, PT mothers reported significantly less child inattention, hyperactivity, oppositional defiance, and emotional lability.
-PT mothers were observed using significantly more positive and less negative parenting.
-PT mothers reported significantly less maternal verbosity and unsupportive emotion socialization practices.

Self-Report of Parenting
(The Parenting Scale)
DISC-IV: -Inattention (α=0.83); -Hyperactivity (α=0.76). Design: -RCT study on weekdays from 9 a.m. to 3 p.m. for 4 weeks in school; -Teachers received 8 hr of training in their intervention condition prior to the summer program; -children attend a summer day program grouped into sameage, same-sex classrooms with previously unacquainted peers; -Each teacher completed a survey to assess buy-in and alliance at the end of the 1 st week and again at the end of the 2 nd week, and their answers were not viewed until after the summer program ended; -COMET's conditions include point check system to learn appropriate behavioral; -MOSAIC's conditions include Social devaluation of ADHD, Behavioral contingency management system, Exclusionary peer behavior, and Reputational bias.
-the main effect for treatment condition on positive nominations was not significant, nor was the interaction between treatment and sex.
-the level of behavior problems displayed by children with ADHD did not differ across treatment conditions, children with ADHD displayed improved sociometric preference and more reciprocated friendships, and received more positive messages from peers, when they were in MOSAIC relative to COMET.
-the beneficial effects of MOSAIC over COMET predominantly occurred for boys relative to girls.

Peer Relationship
Outcomes: -positive nominations (Individual interviews) -negative nominations (Individual interviews) -reciprocated friendships -peer sociometric ratings -peer interactions (record number of interaction from -pre-recorded videos) -messages from peers (score for message)

Inter-rater reliability
-FSS had a significant effect on the quality of the family-school relationship, homework performance, and parenting behavior.

Family involvement in education (PES)
Homework performance (HPC)

ADHD and ODD symptoms (SNAP-IV)
Academic performance (APRS)

Objectives:
(i) to examine feasibility and acceptability and to estimate the efficacy of the program against a referral and treatment as usual control group (TAU) in reducing children's ADHD symptoms (ii) to examine therapeutic effects on the quality of mother-child interaction and mother's mental health (i.e., depression and ADHD symptoms) Participants: -41 children (aged 30-77 months; 31 males, 10 females; -NFPP group (n=21); -TAU control group (n=20).

Design:
-blinded RCT study on 8 week psychological intervention by two part-time nurses; -Outcome measures were collected before treatment (T1), after treatment (week 9; T2) and then at (week 17; T3) for both arms of the trial.
-Effects of the revised NFPP on ADHD symptoms were large (effect size>1) and significant and effects persisted for 9 weeks post-intervention.
-Effects on ODD symptoms were less marked.
-No improvements in maternal mental health or parenting behavior during mother-child interaction although there was a drop in mothers' negative and an increase in their positive comments during a 5 min speech sample.

Skill-building interventions
There were seven studies included in the skill-building interventions targeted primarily at organization skills. The seven studies altogether involved 430 subjects (240 treatment, 190 control) comparing skill-building intervention with control or waitlist ( Table 1). As shown in Figure 4, all the ability-specific interventions were superior to placebo conditions for individuals with AD/HD. The effect size (ES) was 0.366 ranged from 0.307 to 0.425 at 95% CI.

Interaction-oriented interventions
There were six intervention studies included under the interaction-oriented approach: Coaching Our Acting-out Children: Heightening Essential Skills (#5), psychoeducation (#6), Parent training (#9), Classroom inclusion (#12), Family-School Success (#15) and the New forest parenting programme (#17   The six studies altogether involved 435 subjects (280 treatment, 155 control) comparing interaction-oriented interventions with control or waitlist. For the interaction-oriented intervention approach, since Mikami's study (#12) showed an extremely large ES, which would dominate the overall ES and biase the entire analysis, the ES for this approach was done twice, one including the study ( Figure 5) and one without ( Figure 6). The overall interaction-oriented approach to intervention was superior to placebo conditions for individuals with AD/ HD. The effect size (ES) was 0.391 ranged from 0.336 to 0.446 at 95% CI when excluding Mikami's study (#12). The effect size (ES) increased to 0.469 when Mikami's study (#12) was included. In both cases, the interaction-oriented approach to intervention yielded the largest ES among the three intervention approaches.

Overall results of AD/HD interventions
The results of this study highlight the extent of efficacy of the psycho-behavioral intervention framework for individuals with AD/HD. All of the effect sizes (ES) for the study features in the present study are positive ranging from a minimum of .16 (#5) to a maximum of 1.59 (#12). These findings provide supportive evidence for the adoption of the psycho-behavioral interventions to reduce the symptoms for individuals with AD/HD. The results also tend to show that the multi-oriented (skill-building and interaction-oriented) approach to interventions tends to demonstrate the highest efficacy in improving the behavioral performance of individuals with AD/HD.

A shift from management of dysfunction to acquisition of functions
The results of the systematic review seems to confirm our perception that there is a trend from the behavioral management model of AD/HD symptoms focusing on the reduction in dysfunctions to the skill-building model of functional performance  Forest plot with effect size and 95% confidence interval of the six interaction-oriented intervention studies.

Acta Psychopathologica ISSN 2469-6676
related to the daily life requirements of the individuals with AD/ HD following the emergence of the theoretical framework of executive functioning in the 1900's. The AD/HD intervention paradigm has shifted from the general multi-modeled behavioraloriented intervention approach founded on the behavioral management theories and pharmaceutical knowledge-base to those of an ability-specific approach and skill-building approach to interventions.

A shift from unidirectional individual-centered to multi-directional inter-personal orientation
As more literature and related studies on emotional regulation theories have surfaced, the AD/HD approach to intervention has yet further shifted from an individual-centered to that of an inter-personal ecological systems orientation, such as a focus on inter-personal parental interactions [43][44][45]. The study of family dynamics as proposed by family systems theory [46] and emotional security theory [47] have shed us lights on the multidirectional associations between inter-parental and parent-child systems [48,49]. Researchers begin to realize that effective AD/HD intervention does not only rely on uni-directional child-focused training programs, but also on multi-directional interactionoriented inter-personal sub-systems. As a result, measures to evaluate performance or functioning of multiple participants are used, for instances, measures such as the Conflicts and Problem-Solving Scales [50] which assesses constructs such as aggression, avoidance-capitulation and child involvement by mother and father reports of conflict expressions and the Security in the Inter-parental Subsystems Scales [51] that measures adolescents' responses upon witnessing inter-parental conflict. These measures aim to evaluate interaction-oriented constructs such as emotional reactivity, conflict spillover representations, and destructive family representation to indicate their degrees of emotional insecurity in the inter-parental relationship.
In another study [52] that investigated the relationships among adolescents' externalizing behavior problems, characteristics of adolescents' families, their perceived neighborhood support, and their acculturation, various systems centered around the individual with emotion regulatory problems were evaluated. For the family system, measures such as the Lum Emotional Availability of Parents (LEAP) [53] scale which examines participants' perceptions of their mothers' and fathers' emotional availability were used. For community measures, the Sense of Community Index [54] was used to assess neighborhood variables and the Psychological Acculturation Scale [55] was adapted to measure cultural characteristics. For school support system, measures such as the Student Perceived Availability of Social Support Questionnaire [56] were adopted to assess parental and sociocultural variables consistent with several levels of the ecological model.
Last but not least, it can be seen from Table 1 that the psychometric properties of many of the assessment measures used in the three approaches to intervention are not provided in detail. We hope that more vigorous validation processes for newly developed measures can be carried out to ensure that they provide valid evidence for the intervention effectiveness.

Strengths and Limitations of Study
Despite that the interaction-oriented interventions showed better results at follow-up assessments than the other approaches, those results should be interpreted with caution due to the small effect sizes calculations on the measures. If the measurement tool itself was sensitive to the changes caused by the interventions, the effect sizes calculated would be large enough. Another highlighted issue in calculating intervention effectiveness is that those measures with larger sample size contribute more weight to the overall effect-size within the subtype of intervention even the random effect model of analysis was adopted. As for instance, in the interaction-oriented subtype of interventions, the study conducted by Power (#15) has the largest sample size (100 participants in both the control and experimental groups) when compared to the other four studies (14-24 participants in both the control or experimental groups), and the weighting of Mikami's study (#12) was higher than even the sum-up of the other studies. In such cases, those studies would dominate the overall effect. Nonetheless, the quality of the selected studies was seen more important than the sample size of each individual study. In order to ensure the quality of the included studies and minimize the latent threat, a systematic review with a critical appraisal process was adopted in the present study prior to the intervention effectiveness analysis.

Conclusion
Different intervention approaches are founded on different underlying theoretical perspectives of the psycho-behavioral performance in AD/HD. There has been a paradigm shift from the management of dysfunction to the acquisition of functions based on the behavioral management theories and pharmaceutical knowledge-base to those of an ability-specific approach and skill-building approach to interventions for individuals with AD/ HD with the dominance of the theory of executive functioning in the last decades. It is speculated that the trend of AD/HD intervention will continue to shift from that of a uni-directional child-centered approach to those of a multi-directional family ecological systems perspective. This implication calls for more efforts in developing valid assessment measures to evaluate the new constructs assessing the inter-personal relationships within and between the AD/HD individual's ecological systems.