Obesity
Conditions
Keywords
Obesity, weight loss, exercise, diet, phone coaching
Brief summary
The purpose of this study is to examine whether adding phone coaching to an Internet-based weight loss program can improve weight loss outcomes at 4 months and 1 year. All individuals will receive a 4-month, Internet-delivered weight loss program followed by an 8-month Internet-delivered weight loss maintenance program. Some individuals will also be selected to receive either 3 weeks or 12 weeks of phone coaching. Assessments of weight, diet, physical activity, and psychosocial factors will occur at baseline, 4 months, and 1 year.
Detailed description
All individuals enrolled in this study will receive a 4-month Internet-based weight loss program followed by an 8-month Internet-based weight loss maintenance program. During the first 4 months, each week individuals will be asked to view a 10-15-minute multi-media lesson (one per week). These lessons focus on behavioral principles for changing diet and physical activity behaviors. Participants are also given weight loss, calorie intake, and physical activity goals. They are taught how to self-monitor this information and are instructed to submit it weekly on the study website. Automated, weekly individualized feedback is provided. Following the 4-month weight loss program participants will receive an 8-month weight loss maintenance program. During this time, they will be asked to view monthly video lessons which focus on strategies for successful WL maintenance and instructed to continue to self-monitor weight, calorie intake, and physical activity minutes on the study website for one week per month. Automated, monthly feedback is provided. In addition to the Internet program described above, some individuals enrolled in this study will be selected to receive phone coaching. Those selected for 'brief' phone coaching will be asked to complete 3 phone calls with a coach between weeks 5-8 of the study and those selected to receive 'extended' phone coaching will be asked to complete 12 phone calls with a coach between weeks 5-16. The first coaching call will be approximately 45 minutes in duration and all subsequent calls will be approximately 15 minutes in duration. The coach will assist participants in developing a meal plan, problem solving around current barriers, and goal setting. Upon completion of all coaching calls participants will have no additional interaction with the coach, but will remain enrolled in the Internet program. Assessments will occur at baseline, 4, and 12 months.
Interventions
BEHAVIORALInternet-based weight loss program
12-month, Internet-based weight loss/maintenance program.
BEHAVIORALBrief phone coaching
Some individuals will receive 3 weeks of phone coaching. Coaching calls will occur 1x/week, starting at week 5. Once coaching calls are completed, the participant will not have any other contact with their coach.
BEHAVIORALExtended phone coaching
Some individuals will receive 12 weeks of phone coaching. Coaching calls will occur 1x/week, starting at week 5. Once coaching calls are completed, the participant will not have any other contact with their coach.
Sponsors
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
The Miriam Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
Yes
Inclusion criteria
* Age 18-70 * BMI: 25-45 kg/m2 * Regular internet access
Exclusion criteria
* Currently pregnant, \<6 months post-partum, nursing, or planning to become pregnant within the next 12 months. * Current enrollment in a commercial weight loss program or other weight loss research study * Currently taking weight loss medications * Previously had bariatric surgery * Inability to walk 2 blocks without stopping * Any medical condition for which weight loss, dietary restriction, or physical activity is contraindicated
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Percent Weight Change at 4 Months | 4 months after start of weight loss program | Weight change was assessed using weight at baseline and 4 months |
| Percent Weight Change at 12 Months | 12 months after start of weight loss program | Weight change was assessed using weight at baseline and 12 months |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Dietary Intake (Kcals) | 4 months after start of weight loss program | Dietary intake was assessed using self-reported kcal totals obtained from food diaries. The change was calculated from baseline to 4 months. |
| Cost of Supplemental Coaching Per kg of Weight Loss | 12 months after start of weight loss program | Cost-effectiveness analyses were completed to determine the intervention cost per kg of weight loss |
| Video Lesson Viewing | 4 months after start of weight loss program | Percentage of video lessons viewed on study website |
| Self-monitoring of Calorie Intake | 4 months after start of weight loss program | Percentage of days that participant self-monitored their calorie intake on study website |
| Change in Physical Activity Minutes (Min/wk) | 4 months after study enrollment | Physical activity was assessed via Actigraph accelerometers and included moderate-to-vigorous physical activity that was accumulated in bouts of \>=10 minutes. A change score between baseline and 4 months was calculated. |
Countries
United States
Participant flow
Pre-assignment details
Randomization occurred at baseline, but participants were not informed of their randomization assignment until 1 month. Those reporting a 1-month weight then went on to receive brief coaching, extended coaching, or no coaching based upon randomization assignment.
Participants by arm
| Arm | Count |
|---|---|
| Internet Weight Loss + Possibility of Brief Phone Coaching Participants randomized to this group will receive a 4-month, Internet-delivered weight loss program followed by an 8-month, Internet-delivered weight loss maintenance program. All individuals will be taught behavioral strategies for changing diet and physical activity behaviors via video lessons. Some participants in this group will also be selected to receive a brief period (i.e., once/week for 3 weeks) of phone coaching starting at week 5. The first coaching call will be approximately 45 minutes in duration and remaining calls with be 10-15 minutes. Coaches will problem solve with participants and help them develop an individualized meal plan.
Internet-based weight loss program: 12-month, Internet-based weight loss/maintenance program.
Brief phone coaching: Some individuals will receive 3 weeks of phone coaching. Coaching calls will occur 1x/week, starting at week 5. Once coaching calls are completed, the participant will not have any other contact with their coach. | 143 |
| Internet Weight Loss + Possibility of Extended Phone Coaching Participants randomized to this group will receive a 4-month, Internet-delivered weight loss program followed by an 8-month, Internet-delivered weight loss maintenance program. All individuals will be taught behavioral strategies for changing diet and physical activity behaviors via video lessons. Some participants in this group will also be selected to receive an extended period (i.e., once/week for 12 weeks) of phone coaching starting at week 5. The first coaching call will be approximately 45 minutes in duration and remaining calls with be 10-15 minutes. Coaches will problem solve with participants and help them develop an individualized meal plan.
Internet-based weight loss program: 12-month, Internet-based weight loss/maintenance program.
Extended phone coaching: Some individuals will receive 12 weeks of phone coaching. Coaching calls will occur 1x/week, starting at week 5. Once coaching calls are completed, the participant will not have any other contact with their coach. | 148 |
| Internet Weight Loss Only Participants randomized to this group will receive a 4-month, Internet-delivered weight loss program followed by an 8-month, Internet-delivered weight loss maintenance program. All individuals will be taught behavioral strategies for changing diet and physical activity behaviors via video lessons. No participants in this group will receive any phone coaching.
Internet-based weight loss program: 12-month, Internet-based weight loss/maintenance program. | 146 |
| Total | 437 |
Baseline characteristics
| Characteristic | Internet Weight Loss + Possibility of Brief Phone Coaching | Total | Internet Weight Loss Only | Internet Weight Loss + Possibility of Extended Phone Coaching |
|---|---|---|---|---|
| Age, Continuous | 52.2 years STANDARD_DEVIATION 11.5 | 50.8 years STANDARD_DEVIATION 11.4 | 48.5 years STANDARD_DEVIATION 11.4 | 50.7 years STANDARD_DEVIATION 10.9 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 15 Participants | 56 Participants | 23 Participants | 18 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 128 Participants | 381 Participants | 123 Participants | 130 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 2 Participants | 7 Participants | 2 Participants | 3 Participants |
| Race (NIH/OMB) Black or African American | 15 Participants | 39 Participants | 14 Participants | 10 Participants |
| Race (NIH/OMB) More than one race | 4 Participants | 12 Participants | 3 Participants | 5 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 7 Participants | 31 Participants | 13 Participants | 11 Participants |
| Race (NIH/OMB) White | 115 Participants | 348 Participants | 114 Participants | 119 Participants |
| Region of Enrollment United States | 143 participants | 437 participants | 146 participants | 148 participants |
| Sex: Female, Male Female | 101 Participants | 305 Participants | 103 Participants | 101 Participants |
| Sex: Female, Male Male | 42 Participants | 132 Participants | 43 Participants | 47 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk |
|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 143 | 0 / 148 | 0 / 146 |
| other Total, other adverse events | 0 / 143 | 0 / 148 | 0 / 146 |
| serious Total, serious adverse events | 0 / 143 | 0 / 148 | 0 / 146 |
Outcome results
Primary
Percent Weight Change at 12 Months
Weight change was assessed using weight at baseline and 12 months
Time frame: 12 months after start of weight loss program
Population: Reflects the number of participants who completed the 12-month assessment
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Internet Weight Loss + Possibility of Brief Phone Coaching | Percent Weight Change at 12 Months | -4.9 percent change | Standard Deviation 6.1 |
| Internet Weight Loss + Possibility of Extended Phone Coaching | Percent Weight Change at 12 Months | -5.5 percent change | Standard Deviation 6.7 |
| Internet Weight Loss Only | Percent Weight Change at 12 Months | -3.9 percent change | Standard Deviation 7.4 |
Primary
Percent Weight Change at 4 Months
Weight change was assessed using weight at baseline and 4 months
Time frame: 4 months after start of weight loss program
Population: Reflects the number of participants in each treatment arm who completed the 4-month assessment
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Internet Weight Loss + Possibility of Brief Phone Coaching | Percent Weight Change at 4 Months | -6.2 percent change | Standard Deviation 4.7 |
| Internet Weight Loss + Possibility of Extended Phone Coaching | Percent Weight Change at 4 Months | -7.0 percent change | Standard Deviation 5.1 |
| Internet Weight Loss Only | Percent Weight Change at 4 Months | -4.5 percent change | Standard Deviation 4.7 |
Secondary
Change in Dietary Intake (Kcals)
Dietary intake was assessed using self-reported kcal totals obtained from food diaries. The change was calculated from baseline to 4 months.
Time frame: 4 months after start of weight loss program
Population: The participant flow data for this study was based upon whether or not weight (the primary outcome) was measured at each assessment period. Some participants completed a weight assessment at 4 months but did not complete a food diary at this time point. Thus, the number of participants analyzed here is less than what was reported in the Participant Flow.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Internet Weight Loss + Possibility of Brief Phone Coaching | Change in Dietary Intake (Kcals) | -417.78 change in kcals | Standard Deviation 379.62 |
| Internet Weight Loss + Possibility of Extended Phone Coaching | Change in Dietary Intake (Kcals) | -528.51 change in kcals | Standard Deviation 389.79 |
| Internet Weight Loss Only | Change in Dietary Intake (Kcals) | -500.51 change in kcals | Standard Deviation 401.76 |
Secondary
Change in Physical Activity Minutes (Min/wk)
Physical activity was assessed via Actigraph accelerometers and included moderate-to-vigorous physical activity that was accumulated in bouts of \>=10 minutes. A change score between baseline and 4 months was calculated.
Time frame: 4 months after study enrollment
Population: The participant flow data for this study was based upon whether or not weight (the primary outcome) was measured at each assessment period. Some participants completed a weight assessment at 4 months but either did not wear the physical activity monitor or did not wear the monitor for enough days (i.e., 4 or more days with greater than 8 hours of device wear time per day). Thus, the number of participants analyzed here is less than what was reported in the Participant Flow.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Internet Weight Loss + Possibility of Brief Phone Coaching | Change in Physical Activity Minutes (Min/wk) | 55.37 change in min/wk | Standard Deviation 106.82 |
| Internet Weight Loss + Possibility of Extended Phone Coaching | Change in Physical Activity Minutes (Min/wk) | 44.45 change in min/wk | Standard Deviation 108.43 |
| Internet Weight Loss Only | Change in Physical Activity Minutes (Min/wk) | 24.01 change in min/wk | Standard Deviation 94.43 |
Secondary
Cost of Supplemental Coaching Per kg of Weight Loss
Cost-effectiveness analyses were completed to determine the intervention cost per kg of weight loss
Time frame: 12 months after start of weight loss program
Population: The cost of adding supplemental coaching to a pre-existing weight loss program was calculated per enrolled participant. Data was not collected in the Internet Weight Loss Only Arm for this outcome measure since these participants did not receive supplemental coaching.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Internet Weight Loss + Possibility of Brief Phone Coaching | Cost of Supplemental Coaching Per kg of Weight Loss | 13.2 dollars per kilogram of weight loss |
| Internet Weight Loss + Possibility of Extended Phone Coaching | Cost of Supplemental Coaching Per kg of Weight Loss | 30.8 dollars per kilogram of weight loss |
Secondary
Self-monitoring of Calorie Intake
Percentage of days that participant self-monitored their calorie intake on study website
Time frame: 4 months after start of weight loss program
Population: Percentage of days that participants monitored their calorie intake on the study website over the first 4 months of the program (out of 112)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Internet Weight Loss + Possibility of Brief Phone Coaching | Self-monitoring of Calorie Intake | 79.5 % of days | Standard Deviation 27.3 |
| Internet Weight Loss + Possibility of Extended Phone Coaching | Self-monitoring of Calorie Intake | 85.4 % of days | Standard Deviation 23.4 |
| Internet Weight Loss Only | Self-monitoring of Calorie Intake | 66.5 % of days | Standard Deviation 31.4 |
Secondary
Video Lesson Viewing
Percentage of video lessons viewed on study website
Time frame: 4 months after start of weight loss program
Population: Percentage of weekly video lessons that participants viewed over the first 4 months of the program (out of 16)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Internet Weight Loss + Possibility of Brief Phone Coaching | Video Lesson Viewing | 68.7 % of lessons | Standard Deviation 28.9 |
| Internet Weight Loss + Possibility of Extended Phone Coaching | Video Lesson Viewing | 83.0 % of lessons | Standard Deviation 26.6 |
| Internet Weight Loss Only | Video Lesson Viewing | 52.0 % of lessons | Standard Deviation 32.3 |