Cognitive Strategies for Weight Loss

Weight change is the primary outcome in this trial and will be calculated as change from baseline.

Weight change is the primary outcome in this trial and will be calculated as change from baseline.

Weight change is the primary outcome in this trial and will be calculated as change from baseline.

Post-treatment weight change will be calculated as percent weight change observed at the 18 month assessment (6 months following treatment completion)

To address Secondary Aim 1, physical activity (PA) will be objectively-measured for 1 week at baseline, 3m, 12m, and 18m using ActigraphGT9X Link. Participants will be instructed to wear the accelerometer on their waist during all waking hours, exclusive of bathing and swimming, for 7 consecutive days. This monitor uses a validated triaxial accelerometer and proprietary data filtering technology to estimate free-living PA and sedentary behaviors. Accelerometer data will be processed and analyzed using Actigraph's ActiLife software. Data will be considered valid if the monitor was worn for more than 10 hours on more than 4 days (including one or more weekend day). Intensity will be assessed as average counts per minute (cpm) and previously validated cut points (Freedson et al., 1998) will be used to identify bout-related moderate-to-vigorous intensity PA (greater than or equal to 1952 cpm accumulated in bouts greater than or equal to 10 min) and sedentary time (less than 100 cpm).

Diet will be measured through 3, non-consecutive 24-hour diet recalls at baseline, 3m, 12m, and 18m. Recalls will be collected on two weekdays and one weekend at each time point with the first recall collected during the in-person assessment and the subsequent two recalls collected via phone. A trained interviewer will collect recalls using Nutrition Data Systems for Research (NDSR 2018; Nutrition Coordinating Center, University of Minnesota). NDSR uses a multipass method which provides participants multiple opportunities to recall each consumed food/beverage and reduces reporting biases. Given issues with use of dietary recalls to determine absolute energy intake, NDSR output will be used to examine changes in energy density and diet quality, as measured by the Healthy Eating Index, 2015 (HEI-2015). Component scores will highlight changes in intake of fruits and vegetables, whole grains, and lean proteins as well as calories from alcohol, added sugars and energy-dense snacks.

Intervention adherence will be assessed automatically via the study website during the entire 12-month iBWL treatment program. Outcome measures will include number of website number of intervention videos viewed.

Intervention adherence will be assessed automatically via the study website during the entire 12-month iBWL treatment program. Outcome measures will include number of website number of self-monitoring entries during the weight loss program.