Study: NCT04942535

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Social Incentive Gamification
Description: Participants enroll as a family team. They are asked to use a Fitbit activity tracker daily. Each participant sets a daily step goal based on their baseline step count.~Each participant signs a pre-commitment contract. Participants are entered into a game with their family members. Each family receives 70 points weekly. Each day, a family member is selected at random to represent the family. If that person's step goal was achieved, the family keeps its points; if not, they lose 10 points. The participant is notified the following day if they were the family rep.~At the end of the week, if the family has 40 points or more, they advance 1 level. If they have less than 40 points, the family drops down 1 level. Each family team starts in the middle of 5 levels.~At the end of the intervention, families in the top 2 levels receive a small gift.~In the 6 month follow-up, participants receive a daily text message stating whether or not they achieved their step goal on the prior day.

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Social Goals through Incentives to Charity
Description: Participants enroll as a family team. They are asked to use a Fitbit activity tracker daily. Each participant sets a daily step goal based on their baseline step count.~Families select a charity at the beginning of the intervention. They are informed that $20 is available each week to be donated to a charity of their choice. Each day, a family member is selected at random to represent the family. If that person's step goal was achieved, the family gets credit for meeting their goal; if not, the entire family does not get credit. The participant is notified the following day if they were the family rep.~If the family achieves their goal on at least 4 of 7 days in a week, $20 is donated to charity.~In the 6 month follow-up, participants receive a daily text message stating whether or not they achieved their step goal on the prior day.

Intervention type: BEHAVIORAL
Group type: ACTIVE_COMPARATOR
Intervention: Daily Performance Feedback
Description: Participants enroll as a family team. They are asked to use a Fitbit activity tracker daily. Each participant sets a daily step goal based on their baseline step count.~Participants receive a daily text message stating whether or not they achieved their step goal on the prior day.

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Daily Performance Feedback
Description: Participants enroll as a family team. They are asked to use a Fitbit activity tracker daily. Each participant sets a daily step goal based on their baseline step count.~Participants receive a daily text message stating whether or not they achieved their step goal on the prior day.

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Daily Performance Feedback
Description: Participants enroll as a family team. They are asked to use a Fitbit activity tracker daily. Each participant sets a daily step goal based on their baseline step count.~Participants receive a daily text message stating whether or not they achieved their step goal on the prior day.