Measure:

Construct: Source Credibility

Scale description: An 18-item unidimensional 5-point Likert scale (1 = strongly disagree to 5 = strongly agree). Mean scores near 1 indicate that information provided by ALEX was perceived as not credible. Mean scores near 5 indicate the information provided by ALEX was perceived as highly credible. No subscales. The scale includes the following items:

1. Intelligent-Unintelligent-Intelligent
2. Untrained- Trained
3. Doesn't care about me-Cares about me
4. Dishonest- Honest
5. Doesn't have my interests at heart-Has my interests at heart
6. Untrustworthy-Trustworthy
7. Inexpert -Expert
8. Self-centered-Not self-centered
9. Not concerned with me-Concerned with me
10. Dishonorable-Honorable
11. Uninformed-Informed
12. Immoral-Moral
13. Incompetent-Competent
14. Unethical-Ethical
15. Sensitive-Insensitive
16. Stupid-Bright
17. Phony-Genuine
18. Not understanding-Understanding

Construct: Argument Strength; Description: Argument Strength is a 9-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' perceptions of the strength of the argument about colon cancer screening. Mean scores near 1 indicate that ALEX's argument about colon cancer screening was perceived as not strong. Mean scores near 5 indicate that ALEX's argument about colon cancer screening was perceived as very strong. No subscales.

1. The reason ALEX gives me for screening with FIT is believable
2. The reason ALEX gives me for screening with FIT is convincing
3. The reason ALEX gives me for screening with FIT is important to me
4. ALEX helps me feel confident about how best to screen with FIT
5. ALEX would help my friends screen with FIT
6. ALEX encouraged me to screen with FIT
7. ALEX encouraged me to avoid screening.
8. I agree with ALEX's reasoning for screening
9. ALEX gives a strong reason for screening with FIT

Construct: Internal Homophily

Scale: an 8-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' perceptions of their similarity to ALEX's characteristics. Mean scores near 1 indicate participants perceive strong dissimilarity to ALEX's characteristics. Mean scores near 5 indicate participants perceive strong similarity to ALEX's characteristics. No subscales. Items:

1. Doesn't think like me-thinks like me
2. Doesn't behave like me-Behaves like me
3. Is different from me-Is similar to me
4. Unlike me-Is like me
5. Has a background different to mine-Has a background similar from mine
6. Has morals unlike mine-Has morals like mine
7. Looks different from me-Looks similar to me
8. Is a different body size than I am-Has the same body size as I do

Construct: Usability of App; Description: Usability is a 4-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree). This scale measures participants' experience using the ALEX app. Mean scores near 1 indicate a negative experience using the ALEX app. Mean scores near 5 indicate a positive experience using the ALEX app. No subscales. Items:

1. Enjoyable
2. Easy to use
3. Awkward
4. Uncomfortable

Construct: Perceived Severity; Description: A 4-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' perceptions regarding the likelihood of developing colon cancer at some point in their lives. Mean scores near 1 indicate low severity, while mean scores near 5 indicate high severity. No subscales. Items:

1. I am at risk for getting colon cancer in my lifetime.
2. It is possible that I will get colon cancer in my lifetime.
3. I am susceptible to getting colon cancer in my lifetime.
4. It is likely that I will get colon cancer in my lifetime.

Construct: Perceived Susceptibility Description: Perceived Susceptibility is a 4-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) assessing participants' perceptions regarding being susceptible to developing colon cancer at some point in their lives. Mean scores near 1 indicate low susceptibility, while mean scores near 5 indicate high susceptibility. No subscales. Items:

1. I am at risk for getting colon cancer in my lifetime.
2. It is possible that I will get colon cancer in my lifetime.
3. I am susceptible to getting colon cancer in my lifetime.
4. It is likely that I will get colon cancer in my lifetime.

Construct: Response Efficacy Description: A 4-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measured participants' perceptions of the effectiveness of FIT screening in detecting and preventing colon cancer. Mean scores near 1 indicate low perceived efficacy, while mean scores near 5 indicate high perceived efficacy. No subscales. Items:

1. FIT screening leads to early detection if something is wrong.
2. FIT screening leads to the detection of small abnormalities.
3. FIT screening will help me find cancer early.
4. FIT screening will decrease my chances of dying from colon cancer.

Construct: Self-Efficacy Description: A 12-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' confidence in completing FIT screening or a colonoscopy. Mean scores near 1 indicate low self-efficacy, while scores near 5 indicate high self-efficacy. No subscales. Items:

1. I am confident that I can use the FIT
2. Arranging my schedule to use the FIT is an easy thing to do
3. FIT screening would be easy for me to do
4. It would be easy for me to take a stool sample
5. It would be easy for me to mail my kit back
6. It would be easy for me to use all the tools in the kit
7. I know how to collect a stool sample
8. I am confident that I can get a colonoscopy
9. Arranging my schedule to get a colonoscopy is an easy thing to do
10. Finding time to get a colonoscopy would be difficult for me to do
11. Screening for colon cancer with a colonoscopy would be easy for me to do
12. It would be easy for me to get a colonoscopy

Construct: Perceived Barriers Description: A 6-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) assessed participants' perceived obstacles to undergoing FIT screening. Mean scores closer to 1 indicate fewer perceived barriers. Mean scores closer to 5 indicate more perceived barriers. No subscales. Items:

1. My doctor would never recommend the FIT.
2. The FIT would be too expensive.
3. The FIT would be too embarrassing.
4. Preparation for the FIT is too hard.
5. The FIT takes too much time.
6. The FIT is difficult because it is too hard to understand all the instructions.

Construct: Perceived Benefits Description: A 4-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measured participants' perceptions of the benefits of FIT screening. Mean scores near 1 indicate low perceived benefits. Mean scores near 5 indicate high perceived benefits. No subscales. Items:

1. The FIT will decrease my chances of dying from colon cancer.
2. The FIT will help me not worry as much about colon cancer.
3. I believe that if I had a normal screening test result, I wouldn't have to worry about developing colon cancer.
4. I believe that when colon cancer is found early, it can be cured.

Construct: Comparative Risk Feedback Description: A single-item unidimensional measure assessing participants' perceived risk of developing colon cancer compared to others on a 7-point Likert Scale. Mean scores near 1 indicate low perceived comparative risk. Mean scores near 7 indicate a high perceived risk of developing colon cancer compared to others. Item:

1. Compared to the average person your age, gender, and race, how would you rate your chances of developing colon cancer in your life?

Construct: Cancer Information Overload Description: A 4-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' perceptions regarding the amount and clarity of cancer-related information. Mean scores near 1 indicate lower overload. Mean scores near 5 indicate higher overload. No subscales. Items:

1. There are so many different recommendations about preventing cancer, it's hard to know which ones to follow.
2. There is not enough time to do all of the things recommended to prevent cancer.
3. It has gotten to the point where I don't even care to hear new information about cancer.
4. I feel overwhelmed by the amount of cancer information I am supposed to know.

Construct: Perceived Message Relevance Description: A 6-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' perceptions of how relevant and personalized the health message felt to them. Mean scores near 1 indicate low relevance. Mean scores near 5 indicate high relevance. No subscales. Items:

1. The message seemed to be written personally for me.
2. The message was very relevant to my situation.
3. The message was applicable to me.
4. The message was very customized to me.
5. This message was manipulative.
6. This message was misleading.

Construct: Trust in Physician Description: An 11-item 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring physician trust. Mean scores near 1 indicate low trust, while scores near 5 indicate high trust. No subscales. Items:

1. I doubt that my doctor really cares about me as a person
2. My doctor usually puts my needs first
3. I trust my doctor so much I always try to follow his/her advice
4. If my doctor tells me something is so, then it must be true
5. I sometimes distrust my doctor's opinion
6. I trust my doctor's judgments about my medical care
7. I feel my doctor does not do everything he/she should about my medical care
8. I trust my doctor to put my medical needs above all other considerations
9. My doctor is well qualified to manage my medical problems
10. I trust my doctor to tell me if a mistake was made about my treatment
11. I sometimes worry that my doctor may not keep the information we discuss totally private

Construct: Patient-Provider Communication Description: A 5-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' perceptions of how well their doctor communicates with them. Mean scores near 1 indicate poor communication. Mean scores near 5 indicate good communication. No subscales. Items:

1. I receive enough understandable information from my doctor/healthcare provider to make good decisions about my health.
2. I feel rushed during visits.
3. My doctor/healthcare provider involves me in decisions about my health care treatment.
4. I feel uncomfortable asking my doctor for tests or information if he/she doesn't mention it.
5. My doctor/healthcare provider understands my health needs.

Construct: Patient General Health Description: A 3-item unidimensional measure assessing participants' overall health and pain levels on 5-point Likert Scales. Mean scores near 1 indicate low general health. Mean scores near 5 indicate high general health. Items:

1. In general, would you say your health is: (1=Poor, 5=Excellent)
2. How much bodily pain have you had during the past 4 weeks? (1= Very severe, 5= None)
3. During the past 4 weeks, how much did pain interfere with your normal work (including both work outside the home and housework)? (1 = Extremely, 5= Not at all)

Construct: Health Literacy (eHeals) Description: An 8-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' confidence in using the internet for health-related information. Mean scores near 1 indicate low health literacy. Mean scores near 5 indicate high health literacy. No subscales. Items:

1. I know how to find helpful health resources on the Internet.
2. I know how to use the Internet to answer my health questions.
3. I know what health resources are available on the Internet.
4. I know where to find helpful health resources on the Internet.
5. I know how to use the health information I find on the Internet to help me.
6. I have the skills I need to evaluate the health resources I find on the Internet.
7. I can tell high quality from low quality health resources on the Internet.
8. I feel confident in using information from the Internet to make health decisions.

Construct: Interpersonal Distance Description: A 4-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) that measures participants' perceptions of the virtual human's presence. Mean scores near 1 indicate low perceived presence. Mean scores near 5 indicate high perceived presence. No subscales. Items:

1. I perceive that I am in the presence of Alex in the room with me.
2. I feel that Alex is aware of my presence.
3. The thought that Alex is not a real person crosses my mind often.
4. I perceive Alex as being only a computerized image, not as a real person.

Construct: Attitudes towards Fecal Immunochemical Test (FIT) - Sad

Description: We measured participant's emotional attitudes of sadness towards FIT using single-items on a 5-point Likert scale (1=not at all, 5=very much). Mean scores near 1 indicate little to no feelings of sadness regarding FIT screening. Mean scores near 5 indicate strong feelings of sadness regarding FIT screening. Item:

1. How much sadness would you feel if a doctor asked you to get screened for colon cancer using FIT?

Construct: Attitudes towards Fecal Immunochemical Test (FIT) - Worried

Description: We measured participant's emotional attitudes of worry towards FIT using single-items on a 5-point Likert scale (1=not at all, 5=very much). Mean scores near 1 indicate little to no feelings of worry regarding FIT screening. Mean scores near 5 indicate strong feelings of worry regarding FIT screening. Item:

1. How much worried would you feel if a doctor asked you to get screened for colon cancer using FIT?

Construct: Attitudes towards Fecal Immunochemical Test (FIT) - Relieved Description: We measured participant's emotional attitudes of relief towards FIT using single-items on a 5-point Likert scale (1=not at all, 5=very much). Mean scores near 1 indicate little to no feelings of relief regarding FIT screening. Mean scores near 5 indicate strong feelings of relief regarding FIT screening. Item:

1. How relieved would you feel if a doctor asked you to get screened for colon cancer using FIT?

Construct: Attitudes towards Fecal Immunochemical Test (FIT) - Tense

Description: We measured participant's emotional attitudes of tensity towards FIT using single-items on a 5-point Likert scale (1=not at all, 5=very much). Mean scores near 1 indicate little to no feelings of tenseness regarding FIT screening. Mean scores near 5 indicate strong feelings of tenseness regarding FIT screening. Item:

1. How tense would you feel if a doctor asked you to get screened for colon cancer using FIT?

Construct: Attitudes towards Fecal Immunochemical Test (FIT) - Anxious

Description: We measured participant's emotional attitudes of anxiety towards FIT using single-items on a 5-point Likert scale (1=not at all, 5=very much). Mean scores near 1 indicate little to no feelings of anxiousness regarding FIT screening. Mean scores near 5 indicate strong feelings of anxiousness regarding FIT screening. Item:

1. How anxious would you feel if a doctor asked you to get screened for colon cancer using FIT?

Construct: Attitudes towards Fecal Immunochemical Test (FIT) - Calm

Description: We measured participant's emotional attitudes of calmness towards FIT using single-items on a 5-point Likert scale (1=not at all, 5=very much). Mean scores near 1 indicate little to no feelings of calmness regarding FIT screening. Mean scores near 5 indicate strong feelings of calmness regarding FIT screening. Item:

1. How calm would you feel if a doctor asked you to get screened for colon cancer using FIT?

Construct: Attitudes towards Fecal Immunochemical Test (FIT) - Afraid

Description: We measured participant's emotional attitudes of fear towards FIT using single-items on a 5-point Likert scale (1=not at all, 5=very much). Mean scores near 1 indicate little to no feelings of fear regarding FIT screening. Mean scores near 5 indicate strong feelings of fear regarding FIT screening. Item:

1. How afraid would you feel if a doctor asked you to get screened for colon cancer using FIT?

Participants received colorectal cancer screening information using a virtual human that matched their self-reported demographics.

Participants received colorectal cancer screening information using a text-based message that matched their self-reported demographics.

Total of all reporting groups

Participants received colorectal cancer screening information using a text-based message that matched their self-reported demographics.

Participants received colorectal cancer screening information using a virtual human that matched their self-reported demographics.

Participants received colorectal cancer screening information using a text-based message that matched their self-reported demographics.

Measure: Intention to Screen for Colorectal Cancer Item: I want to get screened for colorectal cancer. Scale: 5-point Likert scale (1 = strongly disagree to 5 = strongly agree). Mean scores near 1 indicate a lower intention to get screened for colorectal cancer. Mean scores near 5 indicate a higher intention to get screened for colorectal cancer.

Construct: Behavioral intention to screen No subscales

Measure: Intention to Talk about Screening with FIT Item: I will talk to my healthcare provider about colon cancer screening with FIT.

Scale: 5-point Likert scale (1 = strongly disagree to 5 = strongly agree). Mean scores closer to 1 indicate a lower intention to screen with FIT. Mean scores closer to 5 indicate a high intention to screen with FIT.

Construct: Behavioral intention to screen with FIT No subscales

Measure: Intention to Recommend Intervention (ALEX) Item: Imagine you received a link to ALEX from your healthcare provider. Would you like to share it by sending the link to someone? Scale: 5-point Likert scale (1 = strongly disagree to 5 = strongly agree). Mean scores near 1 indicate a lower intention to recommend ALEX. Mean scores near 5 indicate a high intention to recommend ALEX.

Construct: Behavioral intention to recommend ALEX No subscales

Measure:

Construct: Source Credibility

Scale description: An 18-item unidimensional 5-point Likert scale (1 = strongly disagree to 5 = strongly agree). Mean scores near 1 indicate that information provided by ALEX was perceived as not credible. Mean scores near 5 indicate the information provided by ALEX was perceived as highly credible. No subscales. The scale includes the following items:

1. Intelligent-Unintelligent-Intelligent
2. Untrained- Trained
3. Doesn't care about me-Cares about me
4. Dishonest- Honest
5. Doesn't have my interests at heart-Has my interests at heart
6. Untrustworthy-Trustworthy
7. Inexpert -Expert
8. Self-centered-Not self-centered
9. Not concerned with me-Concerned with me
10. Dishonorable-Honorable
11. Uninformed-Informed
12. Immoral-Moral
13. Incompetent-Competent
14. Unethical-Ethical
15. Sensitive-Insensitive
16. Stupid-Bright
17. Phony-Genuine
18. Not understanding-Understanding

Construct: Argument Strength; Description: Argument Strength is a 9-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' perceptions of the strength of the argument about colon cancer screening. Mean scores near 1 indicate that ALEX's argument about colon cancer screening was perceived as not strong. Mean scores near 5 indicate that ALEX's argument about colon cancer screening was perceived as very strong. No subscales.

1. The reason ALEX gives me for screening with FIT is believable
2. The reason ALEX gives me for screening with FIT is convincing
3. The reason ALEX gives me for screening with FIT is important to me
4. ALEX helps me feel confident about how best to screen with FIT
5. ALEX would help my friends screen with FIT
6. ALEX encouraged me to screen with FIT
7. ALEX encouraged me to avoid screening.
8. I agree with ALEX's reasoning for screening
9. ALEX gives a strong reason for screening with FIT

Construct: Internal Homophily

Scale: an 8-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' perceptions of their similarity to ALEX's characteristics. Mean scores near 1 indicate participants perceive strong dissimilarity to ALEX's characteristics. Mean scores near 5 indicate participants perceive strong similarity to ALEX's characteristics. No subscales. Items:

1. Doesn't think like me-thinks like me
2. Doesn't behave like me-Behaves like me
3. Is different from me-Is similar to me
4. Unlike me-Is like me
5. Has a background different to mine-Has a background similar from mine
6. Has morals unlike mine-Has morals like mine
7. Looks different from me-Looks similar to me
8. Is a different body size than I am-Has the same body size as I do

Construct: Usability of App; Description: Usability is a 4-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree). This scale measures participants' experience using the ALEX app. Mean scores near 1 indicate a negative experience using the ALEX app. Mean scores near 5 indicate a positive experience using the ALEX app. No subscales. Items:

1. Enjoyable
2. Easy to use
3. Awkward
4. Uncomfortable

Construct: Perceived Severity; Description: A 4-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' perceptions regarding the likelihood of developing colon cancer at some point in their lives. Mean scores near 1 indicate low severity, while mean scores near 5 indicate high severity. No subscales. Items:

1. I am at risk for getting colon cancer in my lifetime.
2. It is possible that I will get colon cancer in my lifetime.
3. I am susceptible to getting colon cancer in my lifetime.
4. It is likely that I will get colon cancer in my lifetime.

Construct: Perceived Susceptibility Description: Perceived Susceptibility is a 4-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) assessing participants' perceptions regarding being susceptible to developing colon cancer at some point in their lives. Mean scores near 1 indicate low susceptibility, while mean scores near 5 indicate high susceptibility. No subscales. Items:

1. I am at risk for getting colon cancer in my lifetime.
2. It is possible that I will get colon cancer in my lifetime.
3. I am susceptible to getting colon cancer in my lifetime.
4. It is likely that I will get colon cancer in my lifetime.

Construct: Response Efficacy Description: A 4-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measured participants' perceptions of the effectiveness of FIT screening in detecting and preventing colon cancer. Mean scores near 1 indicate low perceived efficacy, while mean scores near 5 indicate high perceived efficacy. No subscales. Items:

1. FIT screening leads to early detection if something is wrong.
2. FIT screening leads to the detection of small abnormalities.
3. FIT screening will help me find cancer early.
4. FIT screening will decrease my chances of dying from colon cancer.

Construct: Self-Efficacy Description: A 12-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' confidence in completing FIT screening or a colonoscopy. Mean scores near 1 indicate low self-efficacy, while scores near 5 indicate high self-efficacy. No subscales. Items:

1. I am confident that I can use the FIT
2. Arranging my schedule to use the FIT is an easy thing to do
3. FIT screening would be easy for me to do
4. It would be easy for me to take a stool sample
5. It would be easy for me to mail my kit back
6. It would be easy for me to use all the tools in the kit
7. I know how to collect a stool sample
8. I am confident that I can get a colonoscopy
9. Arranging my schedule to get a colonoscopy is an easy thing to do
10. Finding time to get a colonoscopy would be difficult for me to do
11. Screening for colon cancer with a colonoscopy would be easy for me to do
12. It would be easy for me to get a colonoscopy

Construct: Perceived Barriers Description: A 6-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) assessed participants' perceived obstacles to undergoing FIT screening. Mean scores closer to 1 indicate fewer perceived barriers. Mean scores closer to 5 indicate more perceived barriers. No subscales. Items:

1. My doctor would never recommend the FIT.
2. The FIT would be too expensive.
3. The FIT would be too embarrassing.
4. Preparation for the FIT is too hard.
5. The FIT takes too much time.
6. The FIT is difficult because it is too hard to understand all the instructions.

Construct: Perceived Benefits Description: A 4-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measured participants' perceptions of the benefits of FIT screening. Mean scores near 1 indicate low perceived benefits. Mean scores near 5 indicate high perceived benefits. No subscales. Items:

1. The FIT will decrease my chances of dying from colon cancer.
2. The FIT will help me not worry as much about colon cancer.
3. I believe that if I had a normal screening test result, I wouldn't have to worry about developing colon cancer.
4. I believe that when colon cancer is found early, it can be cured.

Construct: Comparative Risk Feedback Description: A single-item unidimensional measure assessing participants' perceived risk of developing colon cancer compared to others on a 7-point Likert Scale. Mean scores near 1 indicate low perceived comparative risk. Mean scores near 7 indicate a high perceived risk of developing colon cancer compared to others. Item:

1. Compared to the average person your age, gender, and race, how would you rate your chances of developing colon cancer in your life?

Construct: Cancer Information Overload Description: A 4-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' perceptions regarding the amount and clarity of cancer-related information. Mean scores near 1 indicate lower overload. Mean scores near 5 indicate higher overload. No subscales. Items:

1. There are so many different recommendations about preventing cancer, it's hard to know which ones to follow.
2. There is not enough time to do all of the things recommended to prevent cancer.
3. It has gotten to the point where I don't even care to hear new information about cancer.
4. I feel overwhelmed by the amount of cancer information I am supposed to know.

Construct: Perceived Message Relevance Description: A 6-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' perceptions of how relevant and personalized the health message felt to them. Mean scores near 1 indicate low relevance. Mean scores near 5 indicate high relevance. No subscales. Items:

1. The message seemed to be written personally for me.
2. The message was very relevant to my situation.
3. The message was applicable to me.
4. The message was very customized to me.
5. This message was manipulative.
6. This message was misleading.

Construct: Trust in Physician Description: An 11-item 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring physician trust. Mean scores near 1 indicate low trust, while scores near 5 indicate high trust. No subscales. Items:

1. I doubt that my doctor really cares about me as a person
2. My doctor usually puts my needs first
3. I trust my doctor so much I always try to follow his/her advice
4. If my doctor tells me something is so, then it must be true
5. I sometimes distrust my doctor's opinion
6. I trust my doctor's judgments about my medical care
7. I feel my doctor does not do everything he/she should about my medical care
8. I trust my doctor to put my medical needs above all other considerations
9. My doctor is well qualified to manage my medical problems
10. I trust my doctor to tell me if a mistake was made about my treatment
11. I sometimes worry that my doctor may not keep the information we discuss totally private

Construct: Patient-Provider Communication Description: A 5-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' perceptions of how well their doctor communicates with them. Mean scores near 1 indicate poor communication. Mean scores near 5 indicate good communication. No subscales. Items:

1. I receive enough understandable information from my doctor/healthcare provider to make good decisions about my health.
2. I feel rushed during visits.
3. My doctor/healthcare provider involves me in decisions about my health care treatment.
4. I feel uncomfortable asking my doctor for tests or information if he/she doesn't mention it.
5. My doctor/healthcare provider understands my health needs.

Construct: Patient General Health Description: A 3-item unidimensional measure assessing participants' overall health and pain levels on 5-point Likert Scales. Mean scores near 1 indicate low general health. Mean scores near 5 indicate high general health. Items:

1. In general, would you say your health is: (1=Poor, 5=Excellent)
2. How much bodily pain have you had during the past 4 weeks? (1= Very severe, 5= None)
3. During the past 4 weeks, how much did pain interfere with your normal work (including both work outside the home and housework)? (1 = Extremely, 5= Not at all)

Construct: Health Literacy (eHeals) Description: An 8-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) measuring participants' confidence in using the internet for health-related information. Mean scores near 1 indicate low health literacy. Mean scores near 5 indicate high health literacy. No subscales. Items:

1. I know how to find helpful health resources on the Internet.
2. I know how to use the Internet to answer my health questions.
3. I know what health resources are available on the Internet.
4. I know where to find helpful health resources on the Internet.
5. I know how to use the health information I find on the Internet to help me.
6. I have the skills I need to evaluate the health resources I find on the Internet.
7. I can tell high quality from low quality health resources on the Internet.
8. I feel confident in using information from the Internet to make health decisions.

Construct: Interpersonal Distance Description: A 4-item unidimensional 5-point Likert scale (1=strongly disagree/5=strongly agree) that measures participants' perceptions of the virtual human's presence. Mean scores near 1 indicate low perceived presence. Mean scores near 5 indicate high perceived presence. No subscales. Items:

1. I perceive that I am in the presence of Alex in the room with me.
2. I feel that Alex is aware of my presence.
3. The thought that Alex is not a real person crosses my mind often.
4. I perceive Alex as being only a computerized image, not as a real person.

Construct: Attitudes towards Fecal Immunochemical Test (FIT) - Sad

Description: We measured participant's emotional attitudes of sadness towards FIT using single-items on a 5-point Likert scale (1=not at all, 5=very much). Mean scores near 1 indicate little to no feelings of sadness regarding FIT screening. Mean scores near 5 indicate strong feelings of sadness regarding FIT screening. Item:

1. How much sadness would you feel if a doctor asked you to get screened for colon cancer using FIT?

Construct: Attitudes towards Fecal Immunochemical Test (FIT) - Worried

Description: We measured participant's emotional attitudes of worry towards FIT using single-items on a 5-point Likert scale (1=not at all, 5=very much). Mean scores near 1 indicate little to no feelings of worry regarding FIT screening. Mean scores near 5 indicate strong feelings of worry regarding FIT screening. Item:

1. How much worried would you feel if a doctor asked you to get screened for colon cancer using FIT?

Construct: Attitudes towards Fecal Immunochemical Test (FIT) - Relieved Description: We measured participant's emotional attitudes of relief towards FIT using single-items on a 5-point Likert scale (1=not at all, 5=very much). Mean scores near 1 indicate little to no feelings of relief regarding FIT screening. Mean scores near 5 indicate strong feelings of relief regarding FIT screening. Item:

1. How relieved would you feel if a doctor asked you to get screened for colon cancer using FIT?

Construct: Attitudes towards Fecal Immunochemical Test (FIT) - Tense

Description: We measured participant's emotional attitudes of tensity towards FIT using single-items on a 5-point Likert scale (1=not at all, 5=very much). Mean scores near 1 indicate little to no feelings of tenseness regarding FIT screening. Mean scores near 5 indicate strong feelings of tenseness regarding FIT screening. Item:

1. How tense would you feel if a doctor asked you to get screened for colon cancer using FIT?

Construct: Attitudes towards Fecal Immunochemical Test (FIT) - Anxious

Description: We measured participant's emotional attitudes of anxiety towards FIT using single-items on a 5-point Likert scale (1=not at all, 5=very much). Mean scores near 1 indicate little to no feelings of anxiousness regarding FIT screening. Mean scores near 5 indicate strong feelings of anxiousness regarding FIT screening. Item:

1. How anxious would you feel if a doctor asked you to get screened for colon cancer using FIT?

Construct: Attitudes towards Fecal Immunochemical Test (FIT) - Calm

Description: We measured participant's emotional attitudes of calmness towards FIT using single-items on a 5-point Likert scale (1=not at all, 5=very much). Mean scores near 1 indicate little to no feelings of calmness regarding FIT screening. Mean scores near 5 indicate strong feelings of calmness regarding FIT screening. Item:

1. How calm would you feel if a doctor asked you to get screened for colon cancer using FIT?

Construct: Attitudes towards Fecal Immunochemical Test (FIT) - Afraid

Description: We measured participant's emotional attitudes of fear towards FIT using single-items on a 5-point Likert scale (1=not at all, 5=very much). Mean scores near 1 indicate little to no feelings of fear regarding FIT screening. Mean scores near 5 indicate strong feelings of fear regarding FIT screening. Item:

1. How afraid would you feel if a doctor asked you to get screened for colon cancer using FIT?

Participants received colorectal cancer screening information using a text-based message that matched their self-reported demographics.

Participants received colorectal cancer screening information using a virtual human that matched their self-reported demographics.

Participants received colorectal cancer screening information using a text-based message that matched their self-reported demographics.