Anger issues are among one of the most frequent reasons for referral to intervention within the developmental population [1]. A significant number of childhood mental health problems, particularly attention-deficit/hyperactivity disorder (ADHD; prevalence of 5%), conduct disorder (CD; prevalence of 4%), and oppositional defiant disorder (ODD; prevalence of 3.3%), have features associated with anger, including irritability and aggression toward others [2]. Evidence suggests that distorted thinking patterns often cause psychosocial interactions to be appraised in a maladaptive manner, triggering anger, aggression, and disruptive behavior [3,4]. To address these cognitive biases, treatment needs to support children in restructuring existing unhelpful thought patterns and equip them with more adaptive response strategies [5].

Cognitive behavioral therapy (CBT) is an approach centered on the conceptual principles outlined above. It has been shown to be efficacious in the treatment of childhood anger problems [6,7]. However, CBT is typically administered through individual and group formats, which could be time-consuming and resource-intensive. Furthermore, parents are often required to accompany the child to see the therapist and this limits the accessibility of treatment [8,9]. Finally, children referred for anger management may not have insight and motivation for change, which are additional barriers for therapy [10]. With advancements in technology, there have been attempts to increase access to therapy through alternatives or adjuncts (eg, computers, internet, and mobile phones) to clinic-based therapy [11-18]. CBT, in particular, is well suited for such adaptations because of its structured and systematic format. A review of the literature indicated that where proven techniques are adapted for computer delivery, clinical outcomes are comparable with traditional face-to-face services [19,20].

Games hold promise in building skills and imparting knowledge to children as they find the interactive features, simulations, and immersive environments both enticing and engaging [21]. The game world is known to be a safe environment to practice behaviors in role-play situations through rule learning and repetition of tasks [22], and it has been demonstrated that games can improve skills in areas such as communication and problem-solving [23]. The use of games for learning, teaching, and psychological interventions is gaining attention. Serious games are defined as entertaining games with non-entertainment goals [24], and such games have adopted the CBT approach to address behavioral and emotional problems in children and adolescents [25,26].

RegnaTales, a series of 6 mobile apps, was created in response to the above advantages of using mobile technology and serious games to increase access to treatment and enhance the motivation of children to learn skills [27,28]. RegnaTales was developed from the Social Problem-Solving Skills Training (SPSST) for anger management [29], based on a cognitive behavioral framework. The SPSST was originally administered in a face-to-face therapy setting through a workbook. It was subsequently developed into a Web-based social problem-solving game, Socialdrome [30] and evolved into the current interactive role-playing game–based mobile apps—RegnaTales. See Multimedia Appendix 1 for screenshots of the RegnaTales mobile apps.

The first 4 mobile apps are game-based apps that teach various anger management strategies, whereas the fifth and sixth apps focus on helping the children apply these skills in their daily lives. The content of each mobile app is listed in Table 1.

In a pilot evaluation of the first RegnaTales mobile game app by Ooi et al [31] conducted in Switzerland, the children found the game highly playable and enjoyable. However, this evaluation was limited in scope because only 1 of the apps was utilized, the number of participants was small, and it was done with a nonclinical population.

The aim of this study was to evaluate RegnaTales in the context of the apps’ usability and playability across domains, including experienced fun, perceived playability, understanding of goals, and perceived impact. In addition, our study explored whether RegnaTales helped in attenuating aggression.

Recruitment took place from November 2015 to December 2017. Participants with a disruptive behavior disorders (DBD) diagnosis were recruited from a psychiatric outpatient clinic in Singapore. According to the Diagnostic and Statistical Manual of Mental Disorders, fourth edition, text revision [32], DBD is a cluster of childhood mental health diagnoses that includes ADHD, ODD, and CD. Flyers were put up in the community to recruit children who have a typically developing (TD) profile.

A total of 72 children aged between 6 and 12 years, comprising those with a clinical diagnosis of DBD and those who were TD, participated in the study. A total of 68 children with DBD were referred for the study by their psychiatrists, of which 35 agreed to participate. The majority of these participants were diagnosed with ADHD only (n=33), whereas 1 had a comorbid diagnosis of ODD and ADHD, and the remaining participant had a diagnosis of CD and ADHD. Another 37 children with a TD profile responded to flyers put up in the community and were recruited for the study. The study was approved by the Domain Specific Review Board (DSRB) of the National Healthcare Group (DSRB 2015/00986). Written informed consent and assent were obtained from the child participants and their parents before commencement of the study procedures.

The 6 RegnaTales apps were developed sequentially, with each app taking about 4 months to develop. Upon completing the development of each app, 12 child participants were recruited to test the app. We tried to recruit an equal number of TD children and children with DBD to test each app. Each RegnaTales app was tested by a different group of 12 child participants. The children played the assigned RegnaTales app on an Apple iPad (9.7-inch screen size) for approximately 50 min before completing the Playability and Usability Questionnaire (PUQ) [31]. They also completed the Reactive-Proactive Aggression Questionnaire [33] before and after the game play. The aggression scores of 2 children using the Abaddon mobile app were not captured because of a technical problem during the research study (ie, data were not captured by the server). The same procedure was followed for each RegnaTales app. Each participant was reimbursed Singapore Dollar $30 at the end of the visit.

RegnaTales was developed using the Corona development platform for mobile apps with the back end running PHP and a MySQL database on a Microsoft Windows Server. RegnaTales has the capability of being ported to various mobile operating systems and devices. Character animation and user interaction were accomplished using Kwik, an Adobe Photoshop plugin. RegnaTales is delivered using the English language.

Independent sample t tests (2-tailed) were used to compare the aggression levels of children with DBD with that of TD children, before using the mobile apps. To understand the participants’ experience of RegnaTales, descriptive statistics were used to present the playability and usability feedback. Mann-Whitney tests (2-tailed) were conducted to examine the differences between children with DBD and TD children in terms of age, playability, and usability scores. Kruskal-Wallis H tests were conducted to examine if there were differences in playability and usability scores among the mobile apps. In addition, Wilcoxon signed rank tests (2-tailed) were conducted to examine if there were changes in aggression after game play. All statistical significance levels were determined at P<.05.

There was a total of 23 female and 49 male participants, aged between 6 and 12 years, with a mean age of 8.79 (SD 1.73) years. Table 2 presents the demographics of the participants for each of the 6 mobile apps. Mann-Whitney tests showed that there were no significant differences in the ages of children in the DBD group and children in the TD group across all 6 mobile apps.

Table 3 shows the RPQ scores of TD children and children with DBD before game play. Independent sample t tests showed that children with DBD had higher reactive aggression, with t₇₀=−2.60 and P=.01; proactive aggression, with t₇₀=−3.58 and P=.001; and overall aggression, with t₇₀=−3.53 and P=.001, on the RPQ as compared with TD children before using the mobile apps.

As shown in Table 4, experienced fun scores ranged from 4.17 (Rage Raver) to 4.67 (RegnaTools). A Kruskal-Wallis H test showed that there were no significant differences in the experienced fun scores across the 6 mobile apps, with χ²₅=0.5 and P=.99. Mann-Whitney tests indicated that there were no significant differences in the experienced fun scores between TD children and children with DBD in each of the 6 mobile apps (see Table 4).

To better understand the participants’ experience of the mobile apps, we looked at the attributes selected by the participants in describing their experience when using each of the 6 mobile apps (Figures 1 and 2).

Generally, half or more participants found the mobile apps exciting, fun, and great. However, less than one-third of them found the apps intuitive and simple.

Figure 2 shows that the mobile apps differed vastly in their difficulty levels. For Village of Lost Expressions and The Illusionist, more than half of the participants found the tasks difficult. However, on the other 4 mobile apps, most participants did not find the tasks difficult.

Figure 3 shows the participants’ responses when asked if they would like to play the various mobile apps again.

With the exception of Rage Raver, all participants indicated either yes or maybe, when asked if they would like to play the apps again and none of the participants indicated no.

As shown in Table 5, curiosity scores ranged from 4.04 (Rage Raver) to 4.54 (The Illusionist). A Kruskal-Wallis H test showed that there were no significant differences in the curiosity scores among the 4 mobile game apps, with χ²₃=2.4 and P=.51. Overall, 38 out of 48 (79%) participants indicated that they wanted to see more of the game world, whereas 41 out of 48 (86%) indicated that they were curious to see what would happen next in the game. Mann-Whitney tests indicated that there were no significant differences in the curiosity scores between TD children and children with DBD in each of the 4 mobile game apps (see Table 5).

As shown in Table 6, perceived playability scores ranged from 3.91 (Rage Raver) to 4.33 (The Illusionist). A Kruskal-Wallis H test showed that there were no significant differences in the perceived playability scores among the 6 mobile apps, with χ²₅=6.3 and P=.28. Mann-Whitney tests indicated that there were no significant differences in the perceived playability scores between TD children and children with DBD in each of the 6 mobile apps, as shown in Table 6.

As shown in Figure 4, more than 50% (6/12) of children agreed/strongly agreed that RegnaTales had good playability features on all domains, with the exception of can play without help, where 33% (4/12) to 58% (7/12) agreed/strongly agreed.

The children indicated the goals of the game apps as the following: save the hero’s parents (39 out of 48, 81%), make friends (19 out of 48, 40%), gain more points and power (21 out of 48, 44%), learn to recognize other’s feelings (34 out of 48, 71%), and learn more about themselves (28 out of 48, 58%).

As shown in Table 7, perceived impact score was 4.40 for RegnaTools and 4.45 for TimeOut!. Mann-Whitney tests indicated that there were no significant differences in the perceived impact scores between children who used RegnaTools and TimeOut!, with U=64.0 and P=.66.

Out of the 24 children who used mobile apps 5 and 6, 19 (79%) agreed/strongly agreed that they were more aware of themselves and their feelings, 23 (96%) agreed/strongly agreed that they had learnt skills to manage their anger, 22 (92%) agreed/strongly agreed that they wanted to learn more skills to manage their anger, 18 (75%) agreed/strongly agreed that they were motivated to use the skills learnt in the mobile apps in their daily lives, and 21 (88%) agreed/strongly agreed that the use of the mobile apps will help them manage their anger. Mann-Whitney tests indicated that there were no significant differences between the TD children and children with DBD in the perceived impact scores for mobile app 5 (RegnaTools), with U=14.5 and P=.62, and mobile app 6 (TimeOut!), with U=16.0 and P=.81.

Wilcoxon signed rank tests indicated that children reported significantly lower reactive aggression after playing the mobile apps Rage Raver, with Z=−2.95 and P=.001; Abaddon, with Z=−2.52 and P=.008; and RegnaTools, with Z=−2.16 and P=.03. Children reported significantly lower overall aggression after playing the mobile apps Abaddon, with Z=−2.52 and P=.008 and RegnaTools, with Z=−2.14 and P=.03. There were no significant changes in proactive aggression in the children after the use of the mobile apps. The results are summarized in Table 8.

To understand if the use of the mobile apps affected the aggression scores of children with DBD differently from TD children, we analyzed the RPQ scores of these 2 groups of children separately for each mobile app, as shown in Table 9.

Wilcoxon signed rank tests showed that TD children who played the Rage Raver mobile app reported significantly lower reactive aggression after game play, with Z=−2.26 and P=.03. DBD children who used the RegnaTools mobile app reported significantly lower reactive and overall aggression after game play, with Z=−2.21, P=.03 and Z=−2.20, P=.03, respectively.

Some limitations should be taken into account when inferring these findings in relation to existing evidence. First, although our study yielded positive results in terms of the level of enjoyment, playability, and perceived impact of RegnaTales, its effectiveness as an anger management intervention has not been fully evaluated. Furthermore, rigorous evaluation is critical through future studies to fully determine whether RegnaTales would bring about improved outcomes in aggression. In our study, each child played through only 1 of the 6 mobile apps, which meant that each child was only exposed to a part of the anger management program. As RegnaTales was developed to be used as a complete program of 6 mobile apps, where anger management skills are progressively taught and built upon one another with a storyline that flows through, it would be more meaningful if each child were to play through all 6 mobile apps. This could yield differing results in terms of playability and changes in aggression scores. In addition, the findings presented should be regarded as preliminary and interpreted in consideration of the absence of a control group and the use of a pre- and postmethodological design. Another limitation is that our participants in the DBD group were all diagnosed with ADHD and only 1 had an additional diagnosis of ODD and 1 with an additional diagnosis of CD. Our DBD group is unlikely to be representative of the broader DBD spectrum, and it may be worthwhile to replicate the study with groups of children with ODD and CD to see if there are differing results. Future research where RegnaTales is being used and evaluated in the children’s natural environment (ie, at home and in school) instead of the clinic setting would be beneficial. Allowing the children to use the mobile apps at their own time and convenience and on their own mobile devices would yield a more accurate picture of the actual usage patterns of the mobile apps. This could also flag practical issues that may affect the usability of the mobile apps (eg, speed and stability of internet connectivity, using the mobile apps on mobile phones with much smaller screens).

Our findings suggest that there is a potential for serious games in mental health interventions for children because of the games’ ability to engage and increase intrinsic motivation. RegnaTales is designed to be a serious game that is self-instructional and does not require explicit teaching or guidance. It is less manpower intensive as compared with face-to-face therapy and would be ideal in the context of soaring demand for mental health services for children amidst a mental health service that is growing at a much slower pace. This study provided positive preliminary findings, primarily in the domains of playability and usability of RegnaTales as a serious game. Coupled with future research to further determine its efficacy in reducing anger issues, RegnaTales could be a potential intervention for clinical as well as nonclinical populations.