Obesity and overweight conditions have become major health challenges worldwide. The exploration of effective weight loss strategies is essential. Nudges are currently advancing approaches that represent a new and better method for changing the behaviors of people. However, the effectiveness of nudge interventions on weight loss in overweight people who may be obese has not been synthesized in a systematic manner. In this study, a systematic literature search was performed. Only randomized controlled trials (RCTs) were considered. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) were calculated as summary statistics. In total, 25 RCTs involving a population of 5,929 individuals were included. Significant effects of the nudge strategy on weight loss (WMD: -0.96 kg, 95% CI: -1.49 to -0.43), body mass index (WMD: -0.3 kg/m2, 95% CI: -0.41 to -0.19) and waist circumference (WMD: -0.75 cm, 95% CI: -1.23 to -0.27) were observed. The subgroup analysis showed that the reduction in body weight associated with nudge interventions was significant in younger and more obese people. Moreover, the effect of nudge intervention on weight loss weakened over time. Overall, the nudge strategy can promote changes in weight loss, body mass index and waist circumference of adults, albeit at a mild magnitude and in particular types of individuals. Nudge strategies can be recommended to clinical practitioners and policy-makers to promote obesity management.

Background In view of the inadequacy and incompleteness of currently-reported animal experiments and their overall poor quality, we retrospectively evaluated the reporting quality of animal experiments published in Chinese journals adhering to the Animal Research: Reporting of In Vivo Experiments (ARRIVE) guidelines. Results The databases CNKI, WanFang, VIP, and CBM were searched from inception until July 2018. Two appropriately-trained reviewers screened and extracted articles independently. The ARRIVE guidelines were used to assess the quality of the published reports of animal experiments. The compliance rate of every item was analyzed relative to their date of publication. A total of 4342 studies were included, of which 73.0% had been cited <= 5 times. Only 29.0% (1261/4342) were published in journals listed in the Chinese Science Citation Database. The results indicate that the compliance rate of approximately half of the sub-items (51.3%, 20/39) was less than 50%, of which 65.0% (13/20) was even less than 10%. Conclusions The reporting quality of animal experiments in Chinese journals is not at a high level. Following publication of the ARRIVE guidelines in 2010, the compliance rate of the majority of its requirements has improved to some extent. However, less attention has been paid to the ethics and welfare of experimental animals, and a number of specific items in the Methods, Results, and Discussion sections continue to not be reported in sufficient detail. Therefore, it is necessary to popularize the ARRIVE guidelines, advocate researchers to adhere to them in the future, and in particular promote the use of the guidelines in specialized journals in order that the design, implementation, and reporting of animal experiments is promoted, to ultimately improve their quality.