The only difference was the type of behavioral therapy used in the telephone coaching sessions.
SBT-only participants were guided by a “control what you can” framework that focused on what they themselves could modify, like whether or not they stocked their kitchen with devil’s food cupcakes, caramel popcorn and other trigger foods. The coaches helped participants cope with cravings and triggers by reinforcing avoidance, that is, telling them to “ignore their cravings” and just focus on their weight loss goal itself.
ACT-only participants were guided by a “control what you can and accept what you can’t” approach. Their coaches taught them to distinguish between what could be modified (cupcakes in the house) versus things that were not under their control, like emotions and food cravings. Instead of ignoring the cravings, participants in the ACT arm were coached to accept the cravings, to notice and allow them, with the goal of just “letting the urge be.” The coaches also advised them to focus on the values that guide their eating behaviors and on physical activity.
Success despite a not-so-smart scale
Overall, Bricker said he was “very pleased” with the results.
“Considering the fact our comparison arm was the gold standard in weight loss intervention which made it a challenging comparison, I think we did really well,” he said.
The study’s primary outcome was a 10% or more loss in total body weight, as reported by the scale and by each participant’s own tracking. Bricker said that 10% weight loss is clinically significant; losing that amount of weight can help prevent diabetes, heart disease and other weight-related health issues.
At three months, data retrieved from the scale found 15% of the ACT participants had lost 10% or more of their weight compared to just 4% of those receiving standard behavioral therapy. At six months, scale data showed 24% of ACT participants had lost 10% or more of their weight compared to just 13% of those in the control SBT arm. At 12 months, however, the scale-reported data showed no change between people who used ACT or SBT. Both arms indicated 30% of participants had lost 10% or more of their total body weight.
Why the weird discrepancy in those last six months? The researchers experienced a technical glitch with the scale.
“We used one that researchers had used before and recommended, but as with all technology you don’t really know how it will perform in your study until you field test it,” Bricker said. “We had a lot of technical problems. The first six months, it wasn’t too bad. But by the time we got to 12 months, they’d started to break down and stopped sending the data.”
Bricker and his team, which included collaborator Dr. Evan Forman of Drexel University in Philadelphia, were able to gather data from the scale for the initial follow-ups. But the only reliable data for the full 12 months came from the participants’ self-reported weight. Those results showed 35% of those who’d used ACT lost 10% or more of their body weight after a year compared to 20% of those who used SBT.
“There was almost perfect concordance between self-report and scale-report, like .999, so we had some trust in it,” Bricker said.
A scientific ‘adventure’
Even the scale snafu provided valuable data, Bricker said.
“We did extensive field testing with six different types after that,” he said. “This was one of the ways we spent our time during the pandemic.”
Bricker said he and others members of the HABIT Lab (Health and Behavioral Innovations in Technology) took the scales home and field tested them, trying them out them on carpet, linoleum and wood floors; weighing themselves at different times of day, using different wireless connections. The team checked to make sure the instructions were easy to follow and that the scales would reliably sync and deliver data.
“I remember having all the scales laid out in my bedroom and my wife came in and said, ‘What are you doing?’” Bricker said. “It was hilarious. But we had to try each one and rate them and find the best one. The experience of that lost data at 12 months was very valuable. With pilot studies, you learn what’s not working and what you have to change and that’s what happened. It was quite an adventure.”
The field testing led the team to select a different smart scale for the larger trial, for which they’re now recruiting participants. This time, the study will enroll 400 people and run for two years instead of one. Bricker’s team of 11 will be joined by Hutch epidemiologist Dr. Anne McTiernan, whose research focuses on preventing disease through lifestyle change.
Trial design will be a much-improved version of the pilot, with the snazzy new scale, the addition of a smartwatch, a bit of training in technical troubleshooting, refinements to the coaching programs, a revised resource guide for participants and the extra year of “booster calls.”
“They’ll get 24 calls in year one and then nine calls in year two,” he said. “It’s a two-year commitment that will address the common problem of weight regain. We also added a Fitbit watch to passively track steps and physical activity and sleep. We’re curious to see if this program has any impact on sleep. And we’ll have a new digital scale tracking their weight, one that’s well-designed with software that’s reliable and syncs well.”