Get Social: Randomized Trial of a Social Network Delivered Lifestyle Intervention

Total time to deliver the intervention and administrative time was tracked during the study for each condition and cost was calculated using national median salary for dietitians \& nutritionists and administrative assistants \& secretaries, and national fringe data for all civilian workers across all industries from Bureau of Labor Statistics. Hourly rate based on salary plus fringe divided by 2080 hours (40 hours/week x 52 weeks). Administrative tasks charged at administrative assistant salary rate, all other treatment delivery tasks charged at dietitian rate. Dollars per participant was calculated by dividing total cost for each condition by the number of participants in that condition.

Administrative and intervention-delivery was measured. Amount of administrative and intervention delivery time per participant was calculated.

Retention will be calculated as the percentage of participants who complete the final weigh-in in each condition.

Acceptability and their satisfaction with intervention was measured by asking participants "If given the opportunity to continue participating in the program, how willing would you be to continue?" Response options were from 1 ("Definitely would") to 5 ("Definitely would not"). The outcome is the number of positive responses which include responses of 1 or 2 ("Probably would") on this measure.

Burden was measured through the question "Participating in the program was time consuming." Response options were 1 ("Strongly agree") to 5 ("Strongly disagree"). We are reporting number of participants who agreed with the statement by responding with a 1 ("Strongly agree") or 2 ("Agree")

National Cancer Institute's (NCI) automated self-administered 24-hour dietary recall (ASA24™) was used to measure caloric intake.

National Cancer Institute's (NCI) automated self-administered 24-hour dietary recall (ASA24™) measured caloric intake. Difference in caloric intake during baseline and 6 month evaluations was calculated.

National Cancer Institute's (NCI) automated self-administered 24-hour dietary recall (ASA24™) will record dietary intake. Change in caloric intake between baseline and 12 months was calculated.

Arizona Physical Activity Questionnaire will be used to provide estimates of total energy expenditure to calculate number of participants reaching the guideline of 150 minutes per week of moderate to vigorous physical activity.

Arizona Physical Activity Questionnaire will be used to provide estimates of total energy expenditure to calculate number of participants reaching the guideline of 150 minutes per week of moderate to vigorous physical activity.

Arizona Physical Activity Questionnaire will be used to provide estimates of total energy expenditure to calculate number of participants reaching the guideline of 150 minutes per week of moderate to vigorous physical activity.

Engagement will be measured by tracking group attendance and quantifying communication in the online group throughout the intervention in terms of percent of intervention modules participated in.

Engagement will be measured by tracking group attendance and quantifying communication in the online group throughout the intervention in terms of percent of intervention modules participated in.

Weight Management Support Inventory to assess social support for weight management. The directions ask respondents to rate on a 5-point scale how frequently they experienced a certain interaction with other people in the past 4 weeks, ranging from 1 (never) to 5 (daily). The items also ask how helpful that event was when it occurred, rated on a 5-point scale ranging from 1 (not helpful) to 5 (extremely helpful). Higher scores indicate more frequent or more helpful social support events. We asked this about four potential social groups: family, friends, friends on Twitter, and friends on Facebook.

Weight Management Support Inventory to assess social support for weight management. The directions ask respondents to rate on a 5-point scale how frequently they experienced a certain interaction with other people in the past 4 weeks, ranging from 1 (never) to 5 (daily). The items also ask how helpful that event was when it occurred, rated on a 5-point scale ranging from 1 (not helpful) to 5 (extremely helpful). Higher scores indicate more frequent or more helpful social support events. We asked this about four potential social groups: family, friends, friends on Twitter, and friends on Facebook.

Weight Management Support Inventory to assess social support for weight management. The directions ask respondents to rate on a 5-point scale how frequently they experienced a certain interaction with other people in the past 4 weeks, ranging from 1 (never) to 5 (daily). The items also ask how helpful that event was when it occurred, rated on a 5-point scale ranging from 1 (not helpful) to 5 (extremely helpful). Higher scores indicate more frequent or more helpful social support events. We asked this about four potential social groups: family, friends, friends on Twitter, and friends on Facebook.

Openness to Experience and Neuroticism/Emotional Stability were measured using the Ten-Item Personality Inventory. The Ten-Item Personality Inventory consists of 10 items that measure the five dimensions of the Five Factor model of personality. Participants are asked to respond to a series of words with personality descriptions with the prompt "I see myself as" with response options of 1 ("Disagree Strongly") to 7 ("Agree Strongly"). Opposite items are reverse coded. Items for Emotional Stability/Neuroticism are "anxious, easily upset" and "calm, emotionally stable". Items for Openness to experience are "open to new experiences, complex" or "conventional, uncreative." The average of the scores represents each dimension with higher scores indicating higher levels of Openness or Emotional Stability (and lower levels of Neuroticism).

Twitter use was measured by asking participants which social networks they had an account on

Participants were asked which social networks they had an account on and number with a Twitter account was reported.

Participants were asked which social networks they had an account on and number with a Twitter account was reported.

The average of two blood pressure readings was used as the measure of blood pressure. If participants only had one blood pressure reading that was used as the measure of blood pressure.

The average of two blood pressure readings was used as the measure of blood pressure. If participants only had one blood pressure reading that was used as the measure of blood pressure.

The average of two blood pressure readings was used as the measure of blood pressure. If participants only had one blood pressure reading that was used as the measure of blood pressure.

Participants completed the four item STOP sleep apnea questionnaire. Participants who answered yes to 0-1 items were classified as low risk for sleep apnea. Participants who answered yes to 2-4 items were classified as high risk for sleep apnea.

Participants completed the four item STOP sleep apnea questionnaire. Participants who answered yes to 0-1 items were classified as low risk for sleep apnea. Participants who answered yes to 2-4 items were classified as high risk for sleep apnea.

Participants completed the four item STOP sleep apnea questionnaire. Participants who answered yes to 0-1 items were classified as low risk for sleep apnea. Participants who answered yes to 2-4 items were classified as high risk for sleep apnea.

To measure sleep quality, participants completed the Insomnia Severity Index. Higher scores (maximum 28) represent increased levels of insomnia, from 0-7 ("Absence of insomnia"), through 8-14 ("Sub-threshold insomnia"), 15-21 ("Moderate insomnia"), and 22-28 ("Severe insomnia").

To measure sleep quality, participants completed the Insomnia Severity Index. Higher scores (maximum 28) represent increased levels of insomnia, from 0-7 ("Absence of insomnia"), through 8-14 ("Sub-threshold insomnia"), 15-21 ("Moderate insomnia"), and 22-28 ("Severe insomnia").

To measure sleep quality, participants completed the Insomnia Severity Index. Higher scores (maximum 28) represent increased levels of insomnia, from 0-7 ("Absence of insomnia"), through 8-14 ("Sub-threshold insomnia"), 15-21 ("Moderate insomnia"), and 22-28 ("Severe insomnia").

To measure sleep quality we used select questions from the Pittsburgh Sleep Quality Index which allowed the calculation of sleep duration.

To measure sleep quality we used select questions from the Pittsburgh Sleep Quality Index which allowed the calculation of sleep duration.

To measure sleep quality we used select questions from the Pittsburgh Sleep Quality Index which allowed the calculation of sleep duration.

Participants were asked whether they had ever been diagnosed with sleep apnea with response options Yes or No.

Participants were asked 1. Are you being treated for sleep apnea presently? (Yes/No) and 2. Have you ever received treatment for sleep apnea?

Participants were asked: Have you ever been diagnosed with sleep apnea? If they answered yes, they were asked if they were currently being treated for sleep apnea.

Participants were asked: Have you ever been diagnosed with sleep apnea? If they answered yes, they were asked if they were currently being treated for sleep apnea.

To measure depressive symptoms, participants completed the Beck Depression Inventory. Total scores can be interpreted as 1-10 ("normal ups and downs"), 11-16 ("Mild mood disturbance"), 17-20 ("Borderline clinical depression"), 21-30 ("Moderate depression"), 31-40 ("Severe depression"), 41+ ("Extreme depression").

To measure depressive symptoms, participants completed the Beck Depression Inventory. Total scores can be interpreted as 1-10 ("normal ups and downs"), 11-16 ("Mild mood disturbance"), 17-20 ("Borderline clinical depression"), 21-30 ("Moderate depression"), 31-40 ("Severe depression"), 41+ ("Extreme depression").

To measure depressive symptoms, participants completed the Beck Depression Inventory. Total scores can be interpreted as 1-10 ("normal ups and downs"), 11-16 ("Mild mood disturbance"), 17-20 ("Borderline clinical depression"), 21-30 ("Moderate depression"), 31-40 ("Severe depression"), 41+ ("Extreme depression").

Participants were asked "Have you ever posted about or had discussions about your weight loss or desire to lose weight?" Number who answered yes are reported.

Participants were asked "Have you ever posted about or had discussions about your weight loss or desire to lose weight?" Number who answered yes are reported.

Participants were asked "Have you ever posted about or had discussions about your weight loss or desire to lose weight?" Number who answered yes are reported.

The intervention was divided into different content units delivered either during a meeting (Traditional Condition) or a series of tweets (Get Social Condition). For the Get Social Condition, tweets with intervention content were produced to meet all objectives for each content unit and programmed to go out at set times for each group so 100% of the objectives for each content unit were met. For the Traditional Condition, checklists were created with objectives for each content unit and staff listened to 2 to 3 randomly selected group recordings for each study wave to determine if these objectives were met by the interventionist. Treatment Fidelity was defined as the percentage of objectives delivered by the interventionist for each wave.

To measure sleep quality we used select questions from the Pittsburgh Sleep Quality Index to calculate habitual sleep efficiency (the percentage of time in bed spent sleeping).

To measure sleep quality we used select questions from the Pittsburgh Sleep Quality Index which allowed the calculation of habitual sleep efficiency (the percentage of time in bed spent sleeping).

To measure sleep quality we used select questions from the Pittsburgh Sleep Quality Index which allowed the calculation of habitual sleep efficiency (the percentage of time in bed spent sleeping).