Obesity: Fothergill et al. (2016)
In The Biggest Loser study, researchers wanted to determine whether extreme weight loss had a long-term effect on metabolism. However, the six-year gap between the initial weight loss and the follow-up testing created what psychologists call a temporal gap problem. Over such a long period, variables like aging, diet, and personal stressors could all have influenced metabolism. This makes it difficult to know whether...