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Using Physical Tracking to Predict Sunburn

Using Retrospective and Real-Time Physical Activity Tracking to Predict Risk of Sunburn in Outdoor Exercisers on Strava

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04977700
Enrollment
41
Registered
2021-07-27
Start date
2020-09-01
Completion date
2023-06-30
Last updated
2023-11-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Prevention

Keywords

skin cancer, physical activity

Brief summary

Recreational UV exposure is associated with every form of skin cancer and individuals who engage in more physical activity have a higher prevalence of sunburn, a proximal biomarker of melanoma risk, perhaps explaining why melanoma is the only cancer with which physical activity is positively correlated. Mobile technology for tracking physical activity has become increasingly prevalent and Strava, an activity tracking app and social networking site for athletes, is one of the most popular of these technologies. This research will test the feasibility of delivering location-based, ecologically-valid sun safety advice to Strava users at times when they are predicted to be engaged in outdoor physical activity, by utilizing Strava's public open-source Applications Programming Interface.

Detailed description

Skin cancer is the most common cancer in the United States. Over 5.4 million cases of keratinocyte cancers (basal and squamous cell) are diagnosed annually and incidence of melanoma has increased 3% each year for the past 30 years. In the 2014 Call to Action to Prevent Skin Cancer, the U. S. Surgeon General included strategies for coordinating messages on sun safety and physical activity, recognizing the need for sun safety among populations that engage in physical activity outdoors. Recreational UV exposure is associated with every form of skin cancer; individuals who engage in more physical activity have a higher prevalence of sunburn. Melanoma is the only cancer with which physical activity is positively correlated. Strava, a tracking app and social networking site for athletes, is one of the most popular of mobile technologies for logging physical activity and providing social feedback on activities by other Strava users. The goal of this R21 research is to test the feasibility of interfacing with the Strava website and its mobile app to develop an algorithm that a) predicts when individuals are likely to be engaged in physical activity outdoors in the sun when ultraviolet radiation is high and b) delivers sun safety advice tailored to the time, location, and personal risk (e.g., skin sun sensitivity) of the Strava users. Concept focus groups with Strava users and non-users will provide input on the feasibility, content, and functions in the Strava Sun (SS) intervention. The algorithm that predicts future outdoor exercise will be developed using machine learning modeling on activity data provided by Strava users. The SS intervention will be programmed to deliver ecologically-valid sun safety advice through Strava's open-source Applications Programming Interface (API) via email and comments in the Strava interface. The sun safety advice will be tailored to location, time, season and user's personal risk, employing advice algorithms we developed for a sun safety mobile app, sunZapp, and a social media message library in our Go Sun Smart intervention for outdoor recreation resorts. SS will be tested for usability prior to conducting a pilot field trial to establish feasibility of SS in practice. The project is significant and innovative. A sun protection interface for the Strava platform will provide individuals who engage in regular physical activity personalized, ecologically-valid advice to help them practice sun safety during outdoor activities. It will contain a novel machine learning algorithm that predicts future high-risk behavior, i.e., outdoor physical activity, to provide precision prevention advice.

Interventions

BEHAVIORALIntervention Group

Test the developed algorithm that delivers location-based, tailored sun safety advice to Strava users through Strava comments for acceptability, ways of interacting with it, and barriers/willingness to allowing access.

Sponsors

National Cancer Institute (NCI)
CollaboratorNIH
Colorado State University
CollaboratorOTHER
Klein Buendel, Inc.
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* 18 or older; reside in the United States; read/write in English; upload outdoor activity to Strava ≥3 times per week

Exclusion criteria

* Younger than 18; reside outside of the United States; read/write in a language other than English; uploads Strava activity less than 3 times per week OR does not use Strava; having a cognitive or visual impairment that would interfere with participating; having another family member participating in the research; having participated in the focus group and usability testing

Design outcomes

Primary

MeasureTime frameDescription
Prevalence of Sun Protection Practicesbaseline and four-weeks post interventionWhat proportion of 8 sun protection practices did participants do on reported days of exercise. Participants responded to 8 potential sun protection practices and provided the number of days they did each practice within the timeframe provided (3 months at baseline; 4 weeks at posttest). Participants also provided number of days of outdoor exercises within timeframe. Proportion was calculated by dividing the frequency of each sun protection practice by the number of days of outdoor exercise within the timeframe. Mean score of all sun protection practices per day of outdoor exercise is reported. Range = 0-1, where a higher number indicates more sun safety practices performed. A proportion was used to account for different timeframes at baseline and posttest.
Prevalence of SunburnBaselineParticipants were asked if their skin was sunburned (described as being red and/or painful from exposure to the sun) in the past three months, and if so, how many times.

Secondary

MeasureTime frameDescription
Physical Activity (Godin Leisure-Time Exercise Questionnaire)BaselineDuration in minutes of exercise multiplied by number of times per week, in the past 7 days. Total minutes per week calculated; mean per treatment group reported.
Recall of Sun Protection Messagesfour weeks post interventionParticipants in intervention only were asked about how many messages they read. Scale ranges from 0 - 3. 0 = none of the messages; 1 = some of the messages; 2 = most of the messages; 3 = all of the messages. Higher score indicates higher message recall.
Self-Efficacy for Sun Protection When Exercisingbaseline and four-weeks post interventionParticipants were asked: how confident are you that you can practice sun safety next time that you exercise. 1 = not confident; 2 = a little confident; 3 = somewhat confident; 4 = very confident. Higher scores indicates more self-efficacy for sun safety.
Range of Physical Activity (Godin Leisure-Time Exercise Questionnaire)baselineDuration in minutes of exercise multiplied by number of times per week, in the past 7 days. Total minutes per week calculated; mean per treatment group reported.

Countries

United States

Participant flow

Pre-assignment details

n=123 participants were recruited and screened for participation in formative research prior to the pilot study detailed, including focus groups, usability testing, and collection of activity data. None of those participants were randomized. n=41 participants participated in the randomized pilot as described in this entry.

Participants by arm

ArmCount
Intervention Group
Participants will be enrolled on a rolling basis and participate in SS for 4 months in the intervention condition. After pretesting, participants will receive sun protection messages from SS through emails/comments based on algorithm results from their profile and activity data. All participants will complete posttest survey 4 months from randomization. Intervention Group: Test the developed algorithm that delivers location-based, tailored sun safety advice to Strava users through Strava comments for acceptability, ways of interacting with it, and barriers/willingness to allowing access.
31
Control Group
A small control group will be included to see if a no-treatment control condition is acceptable to users and estimate follow-up rates for planning a randomized trial. Participants will be enrolled on a rolling basis and will complete a pretest at randomization. All participants will complete a posttest survey 4 months from randomization.
10
Total41

Baseline characteristics

CharacteristicIntervention GroupControl GroupTotal
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
3 Participants3 Participants6 Participants
Age, Categorical
Between 18 and 65 years
28 Participants7 Participants35 Participants
Age, Continuous42.2 years
STANDARD_DEVIATION 14.8
48.9 years
STANDARD_DEVIATION 17.9
43.9 years
STANDARD_DEVIATION 15.7
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants1 Participants1 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
31 Participants9 Participants40 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
3 Participants0 Participants3 Participants
Race (NIH/OMB)
Black or African American
0 Participants0 Participants0 Participants
Race (NIH/OMB)
More than one race
1 Participants0 Participants1 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
1 Participants0 Participants1 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
26 Participants10 Participants36 Participants
Sex: Female, Male
Female
22 Participants7 Participants29 Participants
Sex: Female, Male
Male
9 Participants3 Participants12 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 310 / 10
other
Total, other adverse events
0 / 310 / 10
serious
Total, serious adverse events
0 / 310 / 10

Outcome results

Primary

Prevalence of Sunburn

Participants were asked if their skin was sunburned (described as being red and/or painful from exposure to the sun) in the past three months, and if so, how many times.

Time frame: Baseline

ArmMeasureValue (MEAN)Dispersion
Intervention GroupPrevalence of Sunburn1.0 sunburnStandard Deviation 2.7
Control GroupPrevalence of Sunburn0.2 sunburnStandard Deviation 0.6
Primary

Prevalence of Sunburn

Participants were asked if their skin was sunburned (described as being red and/or painful from exposure to the sun) in the past four weeks, and if so, how many times.

Time frame: four-weeks post intervention

ArmMeasureValue (MEAN)Dispersion
Intervention GroupPrevalence of Sunburn0.3 sunburnStandard Deviation 0.6
Control GroupPrevalence of Sunburn0.3 sunburnStandard Deviation 0.7
Primary

Prevalence of Sun Protection Practices

What proportion of 8 sun protection practices did participants do on reported days of exercise. Participants responded to 8 potential sun protection practices and provided the number of days they did each practice within the timeframe provided (3 months at baseline; 4 weeks at posttest). Participants also provided number of days of outdoor exercises within timeframe. Proportion was calculated by dividing the frequency of each sun protection practice by the number of days of outdoor exercise within the timeframe. Mean score of all sun protection practices per day of outdoor exercise is reported. Range = 0-1, where a higher number indicates more sun safety practices performed. A proportion was used to account for different timeframes at baseline and posttest.

Time frame: baseline and four-weeks post intervention

ArmMeasureGroupValue (MEAN)Dispersion
Intervention GroupPrevalence of Sun Protection Practicesbaseline0.30 proportion of practices/dayStandard Deviation 0.35
Intervention GroupPrevalence of Sun Protection Practicesfour week posttest0.35 proportion of practices/dayStandard Deviation 0.37
Control GroupPrevalence of Sun Protection Practicesbaseline0.43 proportion of practices/dayStandard Deviation 0.43
Control GroupPrevalence of Sun Protection Practicesfour week posttest0.41 proportion of practices/dayStandard Deviation 0.45
Secondary

Physical Activity (Godin Leisure-Time Exercise Questionnaire)

Duration in minutes of exercise multiplied by number of times per week, in the past 7 days. Total minutes per week calculated; mean per treatment group reported.

Time frame: four-weeks post intervention

ArmMeasureValue (MEAN)Dispersion
Intervention GroupPhysical Activity (Godin Leisure-Time Exercise Questionnaire)474.6 minutesStandard Deviation 238.4
Control GroupPhysical Activity (Godin Leisure-Time Exercise Questionnaire)657.5 minutesStandard Deviation 578
Secondary

Physical Activity (Godin Leisure-Time Exercise Questionnaire)

Duration in minutes of exercise multiplied by number of times per week, in the past 7 days. Total minutes per week calculated; mean per treatment group reported.

Time frame: Baseline

ArmMeasureValue (MEAN)Dispersion
Intervention GroupPhysical Activity (Godin Leisure-Time Exercise Questionnaire)578.1 minutesStandard Deviation 603.3
Control GroupPhysical Activity (Godin Leisure-Time Exercise Questionnaire)465.8 minutesStandard Deviation 250.4
Secondary

Range of Physical Activity (Godin Leisure-Time Exercise Questionnaire)

Duration in minutes of exercise multiplied by number of times per week, in the past 7 days. Total minutes per week calculated; mean per treatment group reported.

Time frame: baseline

ArmMeasureValue (MEAN)
Intervention GroupRange of Physical Activity (Godin Leisure-Time Exercise Questionnaire)578.1 minutes
Control GroupRange of Physical Activity (Godin Leisure-Time Exercise Questionnaire)465.8 minutes
Secondary

Range of Physical Activity (Godin Leisure-Time Exercise Questionnaire)

Duration in minutes of exercise multiplied by number of times per week, in the past 7 days. Total minutes per week calculated; mean per treatment group reported.

Time frame: four weeks post-intervention

ArmMeasureValue (MEAN)
Intervention GroupRange of Physical Activity (Godin Leisure-Time Exercise Questionnaire)474.6 minutes
Control GroupRange of Physical Activity (Godin Leisure-Time Exercise Questionnaire)657.5 minutes
Secondary

Recall of Sun Protection Messages

Participants in intervention only were asked about how many messages they read. Scale ranges from 0 - 3. 0 = none of the messages; 1 = some of the messages; 2 = most of the messages; 3 = all of the messages. Higher score indicates higher message recall.

Time frame: four weeks post intervention

Population: Control group participants were not given this item.

ArmMeasureValue (MEAN)Dispersion
Intervention GroupRecall of Sun Protection Messages1.9 units on a scaleStandard Deviation 1
Secondary

Self-Efficacy for Sun Protection When Exercising

Participants were asked: how confident are you that you can practice sun safety next time that you exercise. 1 = not confident; 2 = a little confident; 3 = somewhat confident; 4 = very confident. Higher scores indicates more self-efficacy for sun safety.

Time frame: baseline and four-weeks post intervention

ArmMeasureGroupValue (MEAN)Dispersion
Intervention GroupSelf-Efficacy for Sun Protection When Exercisingbaseline3.1 units on a scaleStandard Deviation 0.9
Intervention GroupSelf-Efficacy for Sun Protection When Exercisingfour-week follow-up3.4 units on a scaleStandard Deviation 0.8
Control GroupSelf-Efficacy for Sun Protection When Exercisingbaseline3.4 units on a scaleStandard Deviation 0.8
Control GroupSelf-Efficacy for Sun Protection When Exercisingfour-week follow-up3.3 units on a scaleStandard Deviation 0.5

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026