Internet-based Tailored Virtual Human Health Intervention to Promote Colorectal Cancer Screening: Design Guidelines from Two User Studies

Abstract

To influence user behaviors, Internet-based virtual humans (VH) have been used to deliver health interventions. However, Internet-based VH health interventions face challenges. The challenges can affect user perceptions of an Internet-based VH health intervention. In our work, we use an Internet-based VH health intervention to promote colorectal cancer (CRC) screening. We present design guidelines drawn from two studies. The two studies examined the influence of visual design and the influence of the information medium on user intentions to pursue more health information. In the first study, the analysis of the focus group (n=73 users) transcripts shows that the VH’s visual realism, the VH’s healthcare role, and the presence of a local healthcare provider’s logo influenced user perceptions of the VH-based intervention’s visual design. The findings from the focus groups were used to iterate the intervention and derive design guidelines. In the second study (n=1,400), the analysis of online surveys of users after the VH-based intervention showed that very few users focused on the VH’s appearance. To influence the user intentions to pursue the health topic further, the results recommend the use of an animated VH to deliver health information compared to other mediums of information delivery, such as text. The design guidelines from the two studies can be used by developers to use VH-based interventions to influence users’ intention to change behaviors.

1. INTRODUCTION

Virtual humans (VH) have been extensively used to deliver health interventions [21, 27]. VH-based health interventions are shown to influence health-related user behaviors, such as reduced alcohol consumption [21] and increased physical activity [27]. VH-based interventions can also be delivered to users using the internet. Internet-based interventions have several advantages. Internet-based interventions can reach a large population outside a clinical setting [13]. Internet-based interventions reduce health service cost compared to a face-to-face intervention [13]. Internet-based interventions increase the convenience for the user to access health information [13].

One potential use of a VH-based health intervention is to increase colorectal cancer (CRC) screening rates in the United States. In the United States, CRC is the second leading cause of cancer deaths among men and women [26]. However, CRC mortality rates can be halved by increasing the rate of early screening [32]. Early CRC screening results in the detection of the early stages of cancer, as well as pre-cancer colon polyps [26]. The early screening rates can be increased by addressing several barriers. Many barriers can prevent patients from accessing early CRC screening rates, including but not limited to: the lack of doctor recommendation to get screened, the public’s lack of awareness about screening options, the fear of cancer and embarrassment, and stigma [19]. To address CRC screening-related barriers, the research team designed a VH-based intervention. The work presented here is part of a multi-year research effort which aims to use ALEX to increase CRC screening among underserved patients, including racial and ethnic minorities and those living in rural communities.

To encourage users to obtain CRC screening, we developed an Internet-based VH intervention called Agent Leveraging Empathy for eXams (ALEX). ALEX uses high-fidelity, 3D VHs with human voices and gestures to deliver CRC screening information. ALEX is presented as a virtual healthcare assistant able to participate in a one-on-one patient-provider conversation. ALEX discusses challenging topics such as the stigma associated with CRC information.

ALEX chooses the VH based on the user’s race and gender. Prior research has shown that the demographic discordance between patients and providers decreases satisfaction with healthcare and lowers patient adherence to guidelines [29]. Therefore, the user’s gender and race were used to determine which ALEX presentation is experienced by user.

ALEX was initially deployed to patients in a focus group setting, followed by testing with users drawn from an online research panel. Drawing on data from these two studies, we developed guidelines for designing VH-based interventions to influence users’ intention to change behaviors. The guidelines address the influence of visual design and the influence of the information medium on user intentions to pursue more health information.

To understand user perceptions related to the visual design of ALEX, we analyzed the data from the focus groups conducted in the prototype development phase of the intervention design [12]. We found that the VH’s role, such as being called a virtual doctor or healthcare assistant, influenced the user expectations for the VH’s appearance. Also, the presence of a local health care provider’s logo was the major source of credibility and trustworthiness for users. The findings were used to make iterative improvements to ALEX (Figure 2b). After implementing the design guidelines from the focus groups, very few users focused on the VH’s appearance.

Figure 2.

(a) VH user interface with text captions for study 2 (b) Upper row- Improved high ftdelity VHs used for study 2. Bottom row - VHs used for study 1. Four versions: (1) White Male (A & E) (2) Black Female (B & F) (3) White Female (C & G) (4) Black Male (D & H). ©University of Florida

To understand the influence of the information medium on the intervention, we analyzed the data from an online research panel. We found that users who experienced the intervention with an animated VH reported greater intention to discuss CRC screening options with a doctor than users who experience the intervention with a static VH or text.

This work contributes the following to research on VH-based interventions: (1) Design guidelines for developing the VH-based interventions based on the insights into the users’ perceptions related to the visual design. 2) An empirical user study comparing the influence of the information medium (animated VH, static VH, and text-based intervention) on user intentions. We provide evidence that a VH-based intervention can be used to influence users’ intentions outside of a controlled lab setting.

2. RELATED WORK

This work builds upon research using motivational VH-based interventions in healthcare and current ways to deliver healthcare interventions for increasing CRC screening rates.

2.1. Virtual Humans in Healthcare

Several studies have compared a VH-based intervention to the existing standard of text-based intervention and have found inconsistent results [21, 27, 30]. For example, Schulman et al. used a VH with synthesized speech and nonverbal behaviors to increase positive attitudes among users [27]. The authors were successful in influencing positive attitudes among users using dialogue strategies. However, there were no differences in persuasiveness between the conventional text-based interface and the VH interface. In the context of handheld computer agents, Bickmore et al. used a VH interface to deliver health information using four different output modalities - text only, a static image with text, animated VH, and animated VH with nonverbal speech (e.g. “uh huh” and “oh”) [2]. The authors found that users rated health information as more credible when delivered via an animated VH. However, the effect of health information on user health behavior was not measured. In similar research by Tielman et al., a VH image with synthesized speech or text delivered psychoeducation. Psychoeducation via text resulted in higher adherence than psychoeducation via synthesized speech [30]. In a study by Lisetti et al., an Internet-based VH intervention was used to reduce alcohol consumption [21]. The authors found that an empathic VH with nonverbal behaviors improved users’ attitudes towards the VH compared to the text-based intervention. However, the authors did not compare the effect of different intervention modes on the outcome, or the change in the user’s attitude towards alcohol consumption. Friederichs et al., used an Internet-based physical activity intervention with text or text and a VH image to induce behavior change [9]. The authors found that the text intervention with a VH image significantly changed user behavior after one month. However, there was no difference compared to text-based intervention.

To deliver health information, we use high-fidelity, 3D VHs with recorded voices and gestures. To understand the influence of information medium on user intentions to pursue more health-related information, we compare the VH-based intervention with the other mediums of information delivery outside the controlled lab setting, in the real context of use.

2.2. Colorectal Cancer Screening and Barriers

In the United States, CRC is the second leading cause of cancer deaths for men and women [26]. The mortality rates can be reduced to approximately half among the adult population when CRC is detected early using screening [32]. However, in 2016, only 67.3% of the US adult population reported using CRC screening [26].

Several barriers contribute to lower CRC screening rates. The major barrier that affects CRC screening is the lack of doctor recommendation to be screened [19]. Although doctors are aware of the benefits of recommending CRC screening, time constraints when meeting with patients limit doctors’ ability to recommend all preventive services to patients [19]. Also, previous research shows that people’s lack of awareness about the benefits of screening and the availability of screening options is another significant barrier affecting screening rates [19]. People also avoid CRC screening due to disgust and social stigma [19]. The stigma associated with performing stool or rectal examination during the CRC screening often leads to screening avoidance [25]. Other barriers include fear of cancer, embarrassment, and failure to schedule screening tests.

Several decision-aids (e.g. pamphlets, digital media, and one-to-one interventions) have been developed to address barriers related to CRC screening [11]. Conventional online text-based interventions, pamphlets, and video clips can address the barrier of lack of patient awareness about CRC. However, conventional intervention methods cannot address the lack of physician recommendation. Whereas, one-to-one interventions with experts (doctors) can address most of the barriers. But the time constraints on doctors limit the number of people going through the intervention.

3. SYSTEM DESIGN

This paper reports on the preliminary design guidelines that emerged from a larger, multi-disciplinary project (see Griffin et al. 2019 for a review [12]). The goal of the larger project is to design and evaluate a tailored Internet-based VH intervention (ALEX) to reduce CRC screening barriers. The screening barriers being reduced are 1) the lack of physician recommendation, 2) the lack of patient awareness about CRC and screening-related information, and 3) users’ fear and embarrassment of discussing CRC. The approach to reducing the screening barriers includes 1) introducing VH as a one-on-one conversation with a “virtual doctor”, 2) informing patients about CRC and screening-related information, and 3) the VH’s dialog with the user was non-judgmental [22] and explained CRC topics.

Demographic discordance reduces patient satisfaction with healthcare and can lead to lower adherence rates to provider recommendations [28]. Therefore, four versions of ALEX were developed so that users could be matched with a VH of the same race and gender: (1) Black Female (2) Black Male (3) White Female (4) White Male as shown in 2b. The VHs were created using Adobe Fuse by the experimenters. The VHs’ high-fidelity voices were recorded by a professional voice talent. Voice talent with the same race and gender of the VH were chosen to match appearance and voice identity. A 3D model of a clinical exam room was used for a virtual environment based on the model’s resemblance to local clinical rooms. In the original intervention prototype, the interface consisted of four components - the VH, text captions, a conversation log, and the interaction buttons. The on-screen buttons were used to take user inputs. After testing with focus groups, the conversation log was eliminated. The VH was in a sitting pose during the intervention and had an idle breathing animation. The text captions of the VH’s audio with the recommended font size [33] were included to assist users with low hearing abilities (refer 2a).

3.1. Developing the Script for Intervention

The research team designed an intervention script in consultation with physicians, communication scientists, and community members. The team included representatives from computer science, oncology, and family medicine. The team also included members of the project’s community advisory board, which was comprised of patient groups, advocates, and medical professionals. The script for intervention is based on ten factors communication scientists have demonstrated to impact cancer screening: message source [15], severity [3], risk probability [10], susceptibility [3], framing [7], benefits [5], response efficacy [6], barriers [14], narrative persuasion [17], and self-efficacy [18]. The research team developed the intervention content iteratively by reviewing with various stake-holders after each draft and incorporating their feedback. These iterations helped improve medical accuracy and user acceptability.

4. INFLUENCE OF VISUAL DESIGN (STUDY 1)

A series of focus groups were conducted as a part of an ongoing larger research effort which aims to use ALEX to increase CRC screening. This work reports on user feedback from the initial thirteen focus groups conducted during the prototype testing phase of the development (during Fall 2017). The focus groups were conducted to aid in the initial development of ALEX before deploying outside of a lab setting. The process involved users interacting with ALEX, filling out a survey, and then participating in a focus group.

4.1. Participants

Our aim was to test ALEX with potential target users within the age range of 50 and 73, the recommended age range for getting screened for colorectal cancer [8]. To conduct a demographically targeted intervention, we needed users who could be demographically matched to our VHs. Therefore, seventy-three participants (21 males, 51 females, 1 not specified), who self-identified as either White or Black, were recruited to participate in the focus groups (refer Table 1 for demographic information). We recruited users through an online program that collects contact information of patients at a local health institution who have agreed to be contacted for qualifying research studies. We also recruited through a local senior center. We used a local senior center as a location for user testing. The senior center was a location that was familiar and readily accessible to the participant pool. We also partnered with a university program, which seeks to engage the public in research and healthcare efforts.

Table 1:

Demographic information for two studies

	Study 1	Study 2
Number of Participants	73	1400
Age Range	50–73 (M=64.42, SD=6.68)	50–73 (M=59.60, SD=6.18)
Race
Black	24	295
White	47	1105
Others	2	0
Gender
Female	51	700
Male	21	700
Not-Specified	1	0

4.2. Measures

In our analysis, we used measures that would align with CRC barriers: the lack of physician recommendation and the lack of patient awareness (Sec. 2.2). A 5-point Likert scale was used to measure users’ intention to discuss screening options with a doctor and learn more about CRC. The measures include: (1) This application made me want to discuss colorectal screening options with my doctor. (2) This application made me want to learn more about my risk for colorectal cancer. Other self-reported measures were collected. For the scope of this paper, we focus on measures related to the influence of ALEX on users’ intention to discuss CRC options with a doctor and learn more about CRC.

4.3. Study Procedure

The goal of the focus groups was to understand the user perceptions of ALEX and discussion about home stool testing recommended by ALEX. Because home stool testing might be considered to be a sensitive topic for conversation, focus groups were conducted separately for male and female participants. Therefore, each session was grouped by user gender and had a moderator and co-moderator who matched the gender of the users.

The moderators collected informed consent from the users and explained the procedures. The focus group participants began by filling out the first part of a questionnaire with items measuring attitudes towards CRC and screening and demographics. After users answered these questions, the users interacted with gender-matched ALEX on a mobile phone provided by the research team. During the intervention, users saw ALEX verbally recite the intervention script for approximately 12 minutes. Users provided information to the VH by selecting between multiple-choice responses during the intervention. For example, users responded to “Do you eat red meat?” by selecting from on-screen options, such as “Yes” and “No”. All users were also recommended to get screened for CRC using the Fecal Immunochemical Test (FIT). The FIT was demonstrated by an animated video. The FIT was chosen because the test can be carried out at home without the need of professional assistance; is less expensive than other home stool tests; and is usually covered by insurance, Medicare, or Medicate. After completing the interaction, they responded to additional questions regarding their opinion of the intervention and the virtual character. Then, they engaged in a group discussion about the intervention and screening.

4.4. Quantitative Results and Discussion

To understand the influence of ALEX on users’ intention a) to discuss CRC screening options with a doctor and b) to learn more about CRC screening options, we analyzed questionnaire data from focus group participants. To analyze the non-parametric Likert scale data, we used the non-parametric Mann-Whitney, Kruskal-Wallis, and One-Sample Wilcoxon Signed Rank tests from SPSS. Since some users chose not to complete some measures, we used the pairwise deletion method to handle the missing data.

User intentions to discuss with the doctor.

A One-Sample Wilcoxon signed-rank test showed that users reported high intentions to discuss CRC screening options with their doctors (n=72, median user rating=4) after going through the intervention, and their scores were significantly higher than a neutral score of 3 (Z=6.087, p<.01).

User intentions to learn more.

A One-Sample Wilcoxon signed-rank test showed that users also reported high intentions to learn more about CRC screening options (n=71, median user rating=4) after going through intervention, and their scores were significantly higher than a neutral score of 3 (Z=5.333 p<.01).

In addition to examining self-reported intentions, we also examined the focus group transcripts and found that users also verbalized these intentions in the group discussions (Sec. 4.5).

An additional analysis was conducted to identify differences between Black and White participants. A Mann-Whitney test indicated that self-rated intentions to learn more about CRC screening options was greater for the Black users (n=24, median user rating = 4) than for the White users after using the intervention (n=47, median user rating = 4), Z = −3.226, p = .001. This is a promising result as ALEX has the potential to help the United States black population who are at high risk of CRC [4].

4.5. Qualitative Results and Discussion

The visual design of the VH can affect user perceptions of the intervention [24]. To understand the influence of the visual design of ALEX on user perceptions, we conducted a qualitative analysis of the focus group transcripts (n=13 focus groups with 73 users). A thematic analysis was followed using an open coding method to identify and cluster codes into common themes. The major themes that emerged centered around trust, user expectations from the VH role, and the influence of VH’s realism. The following major themes were used to derive design guidelines to inform developers of VH-based interventions and improve ALEX.

Use organization branding for building trust.

To increase the trustworthiness of online health information, consumer health portals use measures like source disclosure, ownership disclosure, third-party seals, and branding to build trust with users [23]. Similar to consumer health portals, ALEX used a logo of a local healthcare provider to build trust with users. And as expected, users (in 9 out of 13 focus groups) found information from ALEX credible and trustworthy because it was associated with a local healthcare provider. This theme is illustrated by the following quote: “ …, I think we tend to maybe, stupidly believe that it’s [app] gonna be correct, but uh, I have no reason to doubt UF Health.” [P71]. This observation was not seen across all demographic groups and additional research is necessary to explore how to best use organizational branding. Based on our observation and practices followed by other consumer health portals, we recommend the use of third-party seals and the branding of the credible source to establish credibility in the information provided by a VH. Employing branding measures would specifically benefit the VH-based interventions that are deployed in the general population outside of a controlled lab setting.

Manage expectations associated with VH role.

The VH was introduced as a virtual doctor to increase information credibility. However, introducing the VH as a doctor set user expectations for VH to look and behave like a doctor (in 7 out of 13 focus groups). This theme is evident in the following quotes: “I hadn’t seen many doctors dressed that way. He had his shirt tail out, …” [P19]. And, “Doctors are professionals. They dress appropriately. Doesn’t matter what the age.” [P12]. When these visual expectations were not met by the VH, it affected users’ perceptions of the VH. Given this observation, we recommend VH developers understand user expectations of the VH visual and behavioral representation. This understanding can be captured through focus groups and interviews with potential users.

Influence of VH realism.

Users in 11 out of the 13 focus groups commented on the VH’s visual realism, for example, “I thought that the person in the app wasn’t very realistic. It looked plastic.” [P57]. Users also discussed abnormalities in animations. For example, “it was clearly somewhat awkward, herky-jerky.” [P2] and “Mouth movement fit pretty well with what was going on, but it was not as crisp as it could be.” [P71].

Some users compared the VH to characters from commercial games. This comparison was noted, e.g.„ “…it lacked clarity that modern graphics could provide” [P71]. When asked about initial impressions of application, most users focused their attention on VH’s visual design rather than the CRC information provided from the intervention.

Most users expressed positive reactions to the overall perception of the application (in 11 out of 13 focus groups), e.g., “Something like this could definitely increase screening. There’s no doubt about that.” [P12]. Users noted the quality of the information was the major factor which influenced positive reactions of users, as evident by, “the information was excellent, and especially since I didn’t know a whole lot about using the stool sample, that was good” [P19]. The information from the application was found to be good and easy to follow (in 11 out of 13 focus groups). Although users had several concerns about the VH’s realism, it did not affect users’ perception of the information provided by ALEX.

Use focus groups to identify how to make VH message personally relevant to users.

The focus groups identified how to structure the VH’s message such that the user intended to discuss CRC screening with a doctor. Users in 9 out of the 13 focus groups felt that the intervention was helpful and showed the intention to discuss CRC screening options with a doctor, e.g., “For me direct, I’m gonna ask my doctor on Thursday, I said, what about the FIT test? …” [P4]. And, “It had a lot of information on it that opened my eyes to some things to ask my doctor.” [P51]. Also, some participants expressed their desire to discuss with their doctor before making a decision. E.g., “I would think that that would be a good recommendation to not rely strictly on the information here but go and talk to your doctor about this as an alternative.” [P5]. These reactions, along with the quantitative results (Sec. 4.4), highlight the importance of the user self-identification of the relevance of the VH information to influence behavior.

4.6. Limitations

The limitations include - 1) the focus groups were held with users who were already enrolled in medical research registries or who responded to an invitation to participate in a focus group regarding medical issues. It is possible that such participants have higher levels of health literacy or are simply more interested in health topics than the general population. 2) Although users reported their intentions to discuss CRC screening options with a doctor, we did not do a longitudinal follow-up with users to verify if they screened for CRC. However, this limitation will be addressed in our larger study where we plan to distribute our intervention via an existing healthcare portal and allow users to order screening tests after the intervention.

Based on the focus group feedback, we iterated on the design of ALEX. To address user concerns with realism, we redesigned the VHs to increase their visual and behavioral realism. Visual realism was improved using high fidelity characters as shown in fig. 2b. (see Vilaro et al. 2019 for more details about the visual improvements of the Black Female VH [31]). Behavioral realism was improved using body animations captured using a Vicon Motion Capture System with human actors. To manage user expectations about the VH’s role (Sec. 4.5), the VH is introduced as a virtual healthcare assistant instead of a virtual doctor. The VH attire was changed to match user recommendations and the VH healthcare assistant role by adding a lab coat and an identification badge.

5. INFLUENCE OF INFORMATION MEDIUM (STUDY 2)

VH developers would benefit from a better understanding of how the medium of information delivery would influence users’ intentions to pursue more information on the health topic presented. For example, the information from the CRC intervention could be presented using an animated VH, text with an image of a static VH, or text without the presence of a VH. The question of the influence of the information medium is important for VH developers as different mediums require significantly different amounts of resources to develop. However, if users are more influenced by the information from an animated VH, then the investment in additional resources could be justified.

To compare ALEX with different mediums of information delivery, we designed a between-subject study with three intervention types - animated VH, text with a static image of a VH, and text without a VH. The users in the animated VH condition saw the improved ALEX, verbally going through the custom script authored for this study (Sec. 3.1). The users in the text with a static image of a VH condition saw a textual presentation of the custom script authored for the current study. Finally, users in the text without a VH condition saw an image of a cartoon computer with a stethoscope and the information presented textually with a different script. The script for the control condition contained information about nutrition and cancer prevention based on the American Cancer Society’s guidelines [34]. Figure 3 provides an overview of study conditions. In all the conditions, on-screen buttons were used to take user inputs.

Figure 3.

Different conditions for study 2 ©University of Florida

A secondary hypothesis examined if the VH’s distance from the virtual camera influenced users’ intentions, A VH is a human-like actor delivering the information in front of a camera. Visual framing of the VH conveys different information to the viewer based on the distance between the virtual camera and a VH [16]. For example, a medium shot (showing a VH’s upper-body, arms, and head) is an approximation of how close someone would be in real-world conversations. A medium shot can be used to convey the feeling of intimacy and engage with users at a personal level. While a medium long shot (shows VH from head to knees and surrounding) can be used to show the physical setting around VH to convey contextual information. The information conveyed to users may affect user perceptions [16]. To understand if the VH’s distance from the virtual camera influenced users’ intentions, two additional conditions were added as an exploratory variable: near and far. The users in the near condition saw a VH sitting closer to the camera (showing the VH’s upper-body, arms, and head - Fig 2a) whereas users in the far condition saw a VH sitting farther away from the camera (showing the VH from head to knees and surrounding - Fig 2b).

5.1. Participants

Based on the recommended age range for getting screened for CRC [8], we recruited users (n=1400, 700 males and 700 females) aged 50–73 years during fall 2018 The recruitment was conducted via Qualtrics. The study was conducted online to match the intended real-world use case. The demographic information of users is shown in Table 1.

5.2. Measures

This analysis uses the same measures which were used in the visual design study. We used measures that would align with CRC barriers: the lack of physician recommendation and the lack of patient awareness (Sec. 2.2). We used a 5-point Likert scale to measure users’ intention to discuss screening options with a doctor and learn more about CRC. The measures include: (1) This application made me want to discuss colorectal screening options with my doctor. (2) This application made me want to learn more about my risk for colorectal cancer.

5.3. Procedure

Users were randomly assigned to one of the three conditions - animated VH, text with a static image of a VH, and text without a VH. Users that saw the static or animated VH character were shown a gender-concordant character based on pre-screening questions. Users were randomly shown either a race-concordant or discordant character. The study was designed to match the ideal use case of our intervention: people would receive the intervention through an online link outside of a lab setting. After the intervention, users completed a post-questionnaire survey which involved measures related to influence of ALEX on users’ intentions and an open-ended question about user perceptions of ALEX.

5.4. Results

The main goal of this analysis was to understand the influence of information medium on user intentions to pursue more health information. To analyze non-parametric Likert-scale data, we used non-parametric Kruskal-Wallis H and Mann-Whitney U tests from SPSS. The data from fifty participants were excluded as they filled the survey without going through the full intervention.

User intentions to learn more.

A Kruskal-Wallis H test showed that there was a statistically significant difference in users’ self-rated intentions to learn more about CRC screening options between the animated VH condition, text with a static image of a VH condition, and text without a VH condition, H =12.411, p = 0.002. Post-hoc tests (Dunn’s test) carried out on each pair of groups revealed that there was a significant difference between the control group and the VH group, Z = −3.335, p = 0.003 (adjusted using Bonferroni correction for multiple tests). The results indicate that users in the animated VH group reported greater intention to learn more about CRC screening options than compared to the text without a VH condition after the intervention. There were non-significant differences between the other groups.

User intentions to discuss with the doctor.

A Kruskal-Wallis H test showed that there was a statistically significant difference in users’ self-rated intentions to discuss CRC screening options with a doctor between the animated VH condition, text with a static image of a VH condition, and text without a VH condition, H =18.052, p < 0.001. Post-hoc tests (Dunn’s test) carried out on each pair of groups revealed that there was a significant difference between the text without a VH group and the animated VH group, Z = −3.973, p < 0.001 (adjusted using Bonferroni correction for multiple tests). There was also a significant difference between the text with a static image of a VH group and the animated VH group, Z = −2.505, p = 0.037 (adjusted using Bonferroni correction for multiple tests). These results indicate that users in the animated VH group reported greater intention to discuss CRC screening options with a doctor than compared to the text with a static image of a VH group and the text without a VH group after the intervention.

Effect of camera distance on user motivation.

We also evaluated the effect of VH’s distance from the virtual camera on user intentions. A Mann-Whitney U test showed that there was no statistical difference (p > 0.05) in users’ self-rated intentions to learn more about CRC screening options and discuss CRC screening options with a doctor between the conditions - far and near.

5.5. Discussion for Study 2

Delivering health information as a conversation with an animated VH increased the users’ intention to pursue the health topic further.

The users reported a higher intention to discuss with a doctor in the animated VH condition than both the text with a static image of a VH and text without a VH condition. The users also reported a higher intention to learn more in the animated VH condition than the text without a VH condition. Thus, if the goal of an application is to have users pursue more information on the topic, use an animated VH.

There are multiple factors, such as animations, audio, and interactivity, that differed between the VH condition, the text condition, and the control condition. Each individual factor could have influenced the user intentions in our analysis. As suggested by prior literature, content-related animations and voice can focus people’s attention to information [20] and influence user motivation [1]. However, the impact of individual factors cannot be individually accounted for using the current analysis.

We further wanted to understand the influence of design iterations on user perceptions related to the visual design of the VH. Preliminary analysis of the qualitative data from open-ended responses of the post-questionnaire survey assigned to the VH condition shows that only 10.8% of the 748 user comments focused on concerns related to the VH’s appearance. The analysis shows that comments about the VH’s appearance after the visual improvements of the VHs made up only the minority of all comments.

The limitations of the analysis include: 1) Users were chosen from a Qualtrics users pool that fit the demographics of our target population. These participants are often hired to complete similar surveys and may be more familiar with the online questionnaire format than general users. 2) We did not follow up with users to verify if they discussed CRC screening with a healthcare provider. This limitation will be addressed in a larger study wherein users can self-order screening tests after the intervention.

6. CONCLUSION AND FUTURE WORK

The design guidelines from the focus group and online study can be used by future researchers who intend to use a VH-based intervention to influence users’ intentions.

The analysis of the focus group transcripts from 73 users results in the following guidelines to the visual design when using a VH-based intervention: manage expectations of the VH by testing different VH roles, use organizational branding to build user trust, and use focus groups to identify how messages can be most relevant to users. After implementing the design guidelines from the focus groups, very few users focused on the VH’s appearance.

The analysis of the 1400 online users post-experience survey results in the following guidelines: use animated VHs to influence the users’ intention to pursue the health topic further. Next, we plan to integrate our application in the existing healthcare system to evaluate the VH-based intervention.

Figure 1.

Examples of virtual humans delivering the intervention using different gestures. Virtual humans are tailored to users’ gender and race - A:White Male, B:Black Female, C:White Female, D:Black Male. ©University of Florida

CCS CONCEPTS.

• Human-centered computing → Human computer interaction (HCI).