Background High levels of childhood obesity have been observed globally over the last three decades. Preschools are promising settings to implement obesity prevention interventions in the early years. The aim of this study was to test the feasibility of a cluster randomised controlled trial of the ToyBox-Scotland preschool obesity prevention intervention. Methods Six preschools in predominantly deprived areas of Glasgow, UK, were randomised to either the ToyBox intervention (n = 3) or usual curriculum control group (n = 3). The intervention ran for 18 weeks from March-June 2018, and consisted of practitioner-led physical activity and sedentary behaviour sessions in preschools, with an additional interactive home component. Primary outcome measures were intervention fidelity, recruitment rates, attrition rates, and compliance with trial procedures. Secondary outcomes were body mass index (BMI) z-score, bioelectrical impedance analysis (BIA), objectively measured physical activity and sedentary time via activPAL accelerometer, and parent-reported home eating, snacking, and water consumption. Results The preschool component of the intervention was implemented with high fidelity (64%), while the home component was implemented with low fidelity (41%). A cluster-level recruitment rate of 10% was achieved, and the individual-level recruitment rate was 18% (42/233 children, mean age 4.4 years; 17 girls). The attrition rate was 14%, and compliance rates varied considerably by the outcome. Compliance was highest for BMI (86%), while 19% of the sample returned valid accelerometer data for both baseline and follow-up and the parental questionnaire response rate was 23%. Both intervention and control groups showed small increases in BMI z-scores at follow-up of 0.02 and 0.06, respectively. Both groups had small decreases in physical activity and increases in sedentary time at follow-up. Conclusions Before progression to an effectiveness trial, additional procedures should be considered to improve recruitment rates, compliance with outcome measures, and implementation of the home-based component of the ToyBox-Scotland intervention. Trial registration ISRCTN12831555.

中文翻译：

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学龄前肥胖预防干预的可行性集群随机对照试验：ToyBox-Scotland。

背景 在过去的 30 年中，全球观察到高水平的儿童肥胖症。学前班是在早期实施肥胖预防干预的有希望的环境。本研究的目的是测试 ToyBox-Scotland 学龄前肥胖预防干预的集群随机对照试验的可行性。方法 英国格拉斯哥主要贫困地区的六所学前班被随机分配到 ToyBox 干预组 (n = 3) 或常规课程对照组 (n = 3)。干预从 2018 年 3 月至 6 月持续了 18 周，包括从业者主导的体育活动和学龄前儿童的久坐行为课程，以及额外的互动家庭组件。主要结果指标是干预保真度、招募率、流失率和对试验程序的依从性。次要结果是体重指数 (BMI) z 评分、生物电阻抗分析 (BIA)、通过 activPAL 加速度计客观测量的身体活动和久坐时间，以及父母报告的家庭饮食、零食和饮水量。结果 干预的学前部分以高保真度（64%）实施，而家庭部分以低保真度实施（41%）。集群级招募率为 10%，个体级招募率为 18%（42/233 名儿童，平均年龄 4.4 岁；17 名女孩）。流失率为 14%，依从率因结果而异。BMI 的依从性最高（86%），而 19% 的样本返回了基线和随访的有效加速度计数据，父母问卷回复率为 23%。干预组和对照组均显示 BMI z 分数在随访中小幅增加，分别为 0.02 和 0.06。随访时，两组的体力活动均略有减少，久坐时间有所增加。结论 在进行有效性试验之前，应考虑额外的程序以提高招募率、遵守结果措施以及实施 ToyBox-Scotland 干预的家庭部分。试用注册 ISRCTN12831555。和实施 ToyBox-Scotland 干预的家庭部分。试用注册 ISRCTN12831555。和实施 ToyBox-Scotland 干预的家庭部分。试用注册 ISRCTN12831555。