Development of a Coding Instrument to Assess the Quality and Content of Anti-Tobacco Video Games

Abstract

Previous research has shown the use of electronic video games as an effective method for increasing content knowledge about the risks of drugs and alcohol use for adolescents. Although best practice suggests that theory, health communication strategies, and game appeal are important characteristics for developing games, no instruments are currently available to examine the quality and content of tobacco prevention and cessation electronic games. This study presents the systematic development of a coding instrument to measure the quality, use of theory, and health communication strategies of tobacco cessation and prevention electronic games. Using previous research and expert review, a content analysis coding instrument measuring 67 characteristics was developed with three overarching categories: type and quality of games, theory and approach, and type and format of messages. Two trained coders applied the instrument to 88 games on four platforms (personal computer, Nintendo DS, iPhone, and Android phone) to field test the instrument. Cohen's kappa for each item ranged from 0.66 to 1.00, with an average kappa value of 0.97. Future research can adapt this coding instrument to games addressing other health issues. In addition, the instrument questions can serve as a useful guide for evidence-based game development.

Introduction

Tobacco use is the single most preventable cause of disability, disease, and death in the United States.¹ Each year, more than 480,000 people die prematurely from tobacco use or secondhand smoke exposure.² Smoking is associated with deaths due to heart disease, lung cancer, chronic obstructive pulmonary disease, and many other health issues.² Despite the risks of tobacco use, an estimated 19% of adults and 18% of high school students continue to smoke cigarettes in the United States.³

Public health professionals have developed a wide range of tobacco prevention interventions and policies to address tobacco use in the United States.⁴ One innovative approach being utilized for the prevention and cessation of tobacco uses electronic video gaming. From 1999 to 2009, the percentage of individuals aged 8–18 years old who play video games rose from 38% to 60%.⁵ In a study conducted by the Pew Research Center's Internet American Life Project, researchers found that 47% of teens aged 12–17 years old owned a smartphone, 23% owned a tablet computer, and 93% owned or had access to a computer.⁶ The study also found 95% of the teens are online.⁶ Given the wide-scale use among adolescents and the interactive nature of video games, Internet and mobile application–based video games provide an ideal mechanism for reaching and engaging this population for tobacco prevention and cessation.

Baranowski et al. defined games as “a physical or mental contest with a goal or objective, played according to a framework, or rule, that determines what a player can or cannot do inside a game world.”⁷ Games have been used in several prevention and cessation programs in high school students and adults,^8–11 and previous research has shown the use of electronic games as an effective method for increasing content knowledge about the risks of drugs and alcohol use for adolescents.^12–15 Additionally, researchers found that a computer–based, interactive substance abuse treatment and prevention program increased drug abuse prevention knowledge and decreased the frequency of smoking among adolescents.¹⁶ For example, in a meta-analysis of computer-delivered interventions for alcohol and tobacco use, researchers analyzed the effect sizes from 42 randomized controlled trials, and found the average weighted effect size (d) across the studies to be 0.20, p<0.001.¹⁷ Based on the results of the meta-analysis, the authors concluded that computer-based treatments for tobacco and alcohol consumption can produce significant effects, and are cost-effective and highly accessible.

Several health behavior theories have been used when designing and implementing technology-based tobacco prevention and cessation interventions, such as the Health Belief Model, Social Cognitive Theory (SCT), and the Theory of Planned Behavior (TPB).^18–20 During the development of Pick-Klop, a smoking cessation game, researchers applied constructs from SCT and the TPB, hypothesizing that the modification of attitudes and knowledge toward smoking, as well as confidence in one's ability to quit smoking (i.e., self-efficacy), predicted quitting in smokers.¹⁸ The results from a randomized controlled trial of the Pick-Klop intervention showed a decrease in tobacco use and fewer remaining smokers among the intervention group.¹⁸ The Health Belief Model is also often applied during the development of tobacco prevention and cessation strategies. As part of a quasi-experimental study, researchers applied the Health Belief Model to a smoking cessation intervention with a technology component. In this study, researchers hypothesized that improving individual's knowledge and attitudes specifically related to (a) the severity of smoking, (b) their susceptibility of suffering the side effects of smoking, (c) the benefits of quitting smoking, and (d) methods for overcoming the barriers to quitting would ultimately change their smoking behavior.¹⁹ Results of the study showed significant improvements in smoking behavior among the participants.

The use of interactive components found within games can provide a mechanism to address and change theoretical constructs in a way that promotes engagement and appeals to one's sense of connectedness and self.²¹ Furthermore, video gaming technology appeals to a wide range of individuals, and is able to entertain users while promoting change in theoretical constructs (e.g., attitudes), making it a valuable channel for reaching and engaging individuals for health promotion interventions such as tobacco prevention and cessation.²¹

While there are many tobacco-related games available online or as downloadable versions, little is known about the content and quality of tobacco-specific games. Previous research has examined the content of games in other areas related to health promotion such as exercise,^22–24 but there have been no instruments developed to examine the quality and content of tobacco cessation and prevention-related electronic games systematically. Such an instrument could be used to evaluate existing games and develop future games, which is particularly important given the number of adolescents and young adults actively using game-capable devices. Therefore, the purpose of this article was to describe the development of a coding instrument to examine the type and quality, use of theory, and utilization of health communication techniques of electronic games for tobacco cessation and prevention.

Materials and Methods

Item development

The initial coding instrument draft included 27 overarching categories with 119 specific items. These items covered three overarching video game concepts: game type and quality, theory and approach, and type and format of health messages. A review of relevant literature and review from experts in tobacco prevention and health communication were utilized to inform revisions to the coding instrument. The first full draft of the coding instrument included three main sections: type and quality of game, theory and approach, and type and format of messages, which are each described below.

Type and quality of game

This section measured three areas: type of game, game appeal, and story and characters. These questions were partially informed by Hsu et al.'s work describing six design features important for appealing to game buyers: novelty and powerfulness, appealing presentation, interactivity, challenging, sense of control, and rewarding.²⁵ Within each of these six factors are more specific features, which were used to inform five categories of items in the coding instrument under the category of game appeal: novelty, interactivity, challenging, sense of control, and rewarding. Appealing presentation was excluded because its interpretation was judged to be overly subjective from the expert review.

Another literature resource that informed instrument development was Baranowski et al.'s article exploring the characteristics of 25 video games that included health-related behavior change components.⁷ Their article categorized the games by genre, story, and target group, and these categories and examples helped inform instrument questions and item selections. Health promotion research suggests that stories have the potential for affecting health behavior,²² and two items were developed to measure the presence of story. Items to measure the type of game (i.e., action, adventure, puzzle/strategy, role playing/simulation, quizzes/trivia) were adapted from El-Nasr's book on game analytics.²⁶ After playing a pilot sample of games, it became apparent that a variety of character types appear in games. So, items to assess the types of characters items were developed and added to the instrument (i.e., realistic, unrealistic, human, animals, or nonhuman other than animal). The initial draft had a category to assess population of interest, but this category was removed after expert feedback due to the subjective nature of the assessment.

Theory and approach

This section of the coding instrument measured the theoretical constructs and educational approach used in each video game. According to games for health research, incorporating health promotion theory into games can help make them more effective.^27,28 The items related to theory included in the coding instrument were informed by three major health behavior theories and one communication theory: Health Belief Model, the TPB, SCT, and the Knowledge Gap Theory.^29–32 These theories have been applied to tobacco prevention and cessation among adolescents.^33–35 Furthermore, according to Lu et al., games that are developed using applicable psychological and behavioral theories, such as SCT and TPB, show greater chances of inducing healthy changes in adolescents.²²

Lantz et al. provide three types of educational approaches for tobacco prevention interventions: informational deficit or rational model, affective education model, and social influence resistance model.³⁶ Based on their review, items were added to the video game coding instrument to capture the type of anti-tobacco educational approach used in each game.³⁶

Type and format of message

This section of the video game coding instrument was organized around several sections: type of appeal, type of tobacco messages, message frame, repetition and unique messages, message tailoring, and length of message display. According to Perloff, persuasive messages with factual evidence, as well as an argument that use two-sided arguments (pros and cons), are more likely to be effective,³⁷ and items were developed to examine the message appeal and frame.

Recommendations from the National Cancer Institute suggest that main health promotion messages should be repeated in health communication interventions, which informed the addition of items to measure message repetition.³⁸ The Centers for Disease Control and Prevention guide on health literacy suggests that messages should be tailored to the intended population of interest,³⁹ which informed the addition of items to determine if the messages were generic or tailored to the player. Items to assess message length were developed after playing pilot games when it became apparent that message length varied considerably between games.

Sample game selection

In order to create a list of commercially available tobacco prevention and/or cessation–related video games, a search was conducted via Google and within the two largest online markets for smartphone apps: Google Play for Android smartphones and tablets, and Apple iTunes for iOS iPhone and iPad devices. The first search was conducted over the last 2 weeks of June and the first 2 weeks of July 2013, and an additional search was conducted over the last 2 weeks of November 2013 to update the list and to remove any games from the sample that were no longer available. The following search terms were utilized, although saturation was reached fairly quickly: “smoking prevention games for kids,” “smoking prevention games for youth,” “smoking prevention games for teens,” “anti-tobacco games,” “smoking cessation games,” “smoking prevention,” “quit smoking,” “stop smoking,” and “smoking cessation.” The first 150 links for each search term in the Google search engine were examined for possible inclusion, and all apps in the Google Play and Apple iTunes stores that were found using these search terms were reviewed for possible inclusion.

A sample of tobacco-related video games was created by examining the title and description of each app or Web site. Any app or Web site that indicated it included a game or was itself a game related to smoking cessation or smoking prevention was included on the list, creating an initial total of 151 possible games. When the list was subsequently updated, it was found that 10 games were no longer available, and it was further determined that 12 did not contain a gaming component. Therefore, a total of 129 games were included in the final list to be analyzed.

Expert review

To establish content validity, two experts in tobacco prevention and health communication reviewed the initial draft of the coding instrument to consider the comprehensiveness of the items and to evaluate tobacco prevention strategies and communication methods. The experts were also asked to describe if any items seemed too subjective and should be removed from the coding instrument. Finally, the experts were asked to add, change, or remove items based on their knowledge of tobacco prevention communication strategies. When necessary, experts met to discuss any disagreements in order to provide a consensus answer.

Pilot tests

Two trained coders independently conducted a pilot test using the 11 games from the various platforms (see Table 1). Coders played each game five times through from beginning to end, or for 15 consecutive minutes, whichever was shorter. Coders then coded each of the games, referring back to the game as needed. The items on the checklist were categorized as dichotomous variables, “1” if it was present in the game, “0” if not. Cohen's kappa values were calculated for each item to determine the level of rater agreement per item. The games were pilot tested a total of five times, with minor revisions to the instrument and coding instructions, until an acceptable average kappa was obtained, and each item had a Cohen's kappa ≥0.70. Kappa values between 0.61 and 0.80 are considered substantial agreement.^40–42 Kappa values were calculated using IBM SPSS Statistics for Windows v21 (IBM Corp., Armonk, NY).

Table 1.

Games Used in Pilot Test

Game	Platform
Blast a Butt	Computer
Butt Out Tobacco Trivia	Computer
Crave Out!	iTunes
Don't Blow It	Google Play
Smoking Time Machine	Google Play
Stamp Out Smoking	Computer
Tobacco Free Teens	Computer
Type or Die	Computer
Up in Smoke	iTunes
Wak-a-monsta	Google Play
What's Your Come Back	Computer

Field test

The same two trained coders used the latest form of the coding instrument to code the sample of tobacco-related games retrieved from the Internet search (n=121). Some games (n=8) had become unavailable since the Internet search and were removed from the list of games to code. Games that required users to play the game over several days in order to gain access to the majority of the game content were excluded from the study. In total, 88 games (74.4%) were coded in the field test. The Cohen's kappa was obtained for each item, and ranged from 0.66 to 1, with an average kappa of 0.97. Cronbach's alpha (α=0.70) was used to measure the internal consistency of the items (n=17) measuring the construct “game appeal.” The entire instrument development process is described in Table 2.

Table 2.

Overview of Coding Instrument Development

Stage	Description	Process
1	Identifying existing tobacco prevention and cessation games	Google search for key terms, 141 games retained, 12 removed that did not meet criteria, 129 remained
2	Review content of sample of games	11 games representing the three different platforms played to determine amount of time appropriate to gain idea of game content
3	Identifying best practices in relevant literature	Review literature to determine common characteristics of coding instruments and theoretical concepts and important characteristics related to tobacco prevention and cessation messaging
4	Initial item development	27 items developed based on literature review; three main sections: type and quality of game, theory and approach, and type and format of messages
5	Expert review	One tobacco expert and one health communication expert were asked to review coding instrument
6	Pilot tests	11 games coded, coding instrument revised until kappa values on each item were at least 0.70, coding instrument was pilot tested and revised five times
7	Coding guide developed	Using feedback from experts, coding guide was developed
8	Field test	Total sample of identified games were coded, each item was analyzed, experts were used to settle any disagreements, problem items removed

Results

The categorical sections of the final coding instrument included type and quality of games, theory and approach, and type and format of messages. The final version of the coding instrument can be found in Appendix 1. The majority of the items (67/72, 93.1%) were retained. From the initially developed items (119 items), 51 items were removed after expert review, pilot testing, and field testing.

Items were removed if the item seemed too subjective, received low interrater reliability, or experts suggested removing the item. Items (n=7) related to novelty (one of the characteristics of game appeal) were removed because the items were too subjective. Example item: scenarios are unpredictable, game characteristics were colorful or vibrant, audio matches the emotion of the game. Items related to target audience (n=4) were removed after low interrater reliability. Several items (n=26) related to constructs were removed after expert review showed overlap in many of the constructs. Items related to health education approach (n=5) were removed, as experts decided these items overlapped with other educational approach items. Items related to type of argument, biased and neutral statements, fear, and type of appeal were removed (n=6) after consistently receiving low interrater reliability and expert decision that these items were too subjective to include in the instrument. The final coding instrument contained 67 characteristics under three overarching categories: type and quality of games, theory and approach, and type and format of messages.

The type and quality section contains a total of 28 items, which are subdivided into seven sections: “type of game” (6 items), “interactivity” (3 items), “challenging” (2 items), “sense of control” (4 items), “rewarding” (6 items), “story” (2 items), and “characters” (5 items). The sections “interactivity,” “challenging,” “sense of control,” “rewarding,” and “story” measure game appeal.

The theory and approach section contains a total of 11 items, which are subdivided into two sections: “theoretical constructs” (8 items) and “educational approaches” (3 items).

The final section, type and format of messages, contains a total of 27 items, which are subdivided into 7 sections: “type of appeal” (2 items), “type of tobacco message” (14 items), “message framing” (2 items), “type of argument” (2 items), “message characteristics” (3 items), and “message displayed” (4 items).

Discussion

The results of this methodological study provide a coding instrument for describing the content of tobacco prevention and cessation games. The instrument could be used to evaluate current games to understand what strengths and deficiencies they contain related to theoretical and educational approaches from the current health communication and tobacco prevention and cessation literatures. While selected items were removed during the process from the initial item bank, only items that the experts felt were objective, represented important characteristics of tobacco prevention and cessation and health communication, consistently had high interrater reliability, were retained in the final instrument.

This video game coding instrument can also be used as a resource while developing new video games for tobacco prevention or cessation to determine the game quality and appeal, theoretical construct inclusion, and message content frame and approach. Furthermore, health promotion professionals could adapt this instrument as a tool for determining which games may be the best resource for health promotion programs and interventions.

Researchers or other professionals wishing to use this instrument should use the coding guide developed for the instrument, which provides a detailed description of how to interpret each of the items included in the instrument. Users should also be familiar with the intended use of the instrument and how to interpret findings. This coding instrument was designed with the purpose of describing characteristics of games related to the prevention and cessation of tobacco use. Based on the use in this study, the coding instrument may not be appropriate for games that cannot be completed in one setting. In addition, this instrument may not be appropriate for games that are primarily trackers or apps with a sole purpose to track the number of cigarettes or other behaviors over a period of time. Finally, it is important to note that the coding instrument is a descriptive tool, not a scale or scales, as the categories do not represent overarching constructs.

Items in the coding instrument should be selected if the game content contains the item characteristic. Because there are multiple sections, a summed total for the instrument is not appropriate and higher values cannot be seen as “better” games. Therefore, this instrument is intended to allow users to understand the characteristics of the games. The characteristics that are important for the game depends on the purpose of the game. For example, research suggests the characteristics used for describing “game appeal” are important elements of making a game appealing.^7,25 There are a total of 17 characteristics in the instrument related to “game appeal”: interactivity (3 items), challenging (2 items), sense of control (4 items), rewarding (6 items), and story (2 items). A higher number of these characteristics could make the game more appealing.

Similarly, games should apply theoretical constructs, as research suggests games that utilize theory are important for developing effective games.^27,28 This would be relevant when examining the theoretical constructs and educational approaches used by the games. Games should address at least one theoretical construct and could apply more than one educational approach.

Finally, when examining the number of tobacco messages, one should consider that the Centers for Disease Control and Prevention suggests health communication products should contain no more than three or four points.³⁹ Recommendations also suggest two-sided arguments are more likely to alter attitudes than one-side arguments.³⁷ For example, a game with a two-sided argument would provide the benefits of quitting smoking (e.g., decreased heart disease risk) and the potential difficulties associated with quitting (e.g., irritability). Additionally, a message that provides evidence is more likely to be effective than those message that lack evidence.³⁷ According to the Centers for Disease Control and Prevention,⁴ “messages that elicit strong emotional response, such as personal testimonials and viscerally negative content, produce stronger and more consistent effects on audience recall, knowledge, beliefs and quitting behaviors.” Furthermore, health communication messages that are tailored to their population of interest are more successful than those that do not.³⁹

Limitations

The games used for the development of the coding instrument were those available during the time frame of the development process. Additionally, not all gaming platforms were included, although popular platforms were selected for the process. Behavioral tracking applications and games that required play over a period of several days to gain access to game content were also not included in the analysis. It is possible that other games that were not included in this study may have affected the development of the coding instrument.

Conclusion

As game-capable devices continue to be widely used among adolescents and young adults, researchers should be able to determine which games present characteristics that promote tobacco prevention and cessation. The coding instrument developed in this article provides a tool for researchers in the public health field to evaluate the content and quality of tobacco-related games. The instrument allows researchers to describe games based on the game type and quality, use of theory, and educational and messaging approaches. The coding guide should be used to ensure proper use and interpretation of the coding instrument. Future research should explore applying this coding instrument to tracking applications and repeated-play games that take longer than one setting to complete. In addition, practitioners and game developers should consider using and/or adapting this coding instrument to help inform effective game development.

Footnotes

Acknowledgments

The work was supported by the Food and Drug Administration (FDA) Center for Tobacco Products and the National Cancer Institute (NCI) Office of Communication and Education. The content is solely the responsibility of the authors and does not necessarily represent the official views of the FDA, NCI, or NIH.

Author Disclosure Statement

No competing financial interests exist.

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