BACKGROUND Little is known about duration of exposure to the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) in relation to children's diet quality. OBJECTIVE The objective of the study was to examine the association between duration of WIC participation and diet quality of 24-month-old children. DESIGN A national longitudinal observational study was conducted with participants initially enrolled in WIC in 2013. Telephone interviews were conducted with study mothers from 2013 to 2016. Duration of WIC participation was categorized as high, medium, or low based on the number of interviews during which participants reported receiving WIC benefits. PARTICIPANTS Participants in the WIC Infant and Toddler Feeding Practices Study 2 who had completed a baseline interview and all interviews through 24 months were included; participants who reported discontinuing WIC due to perceived program ineligibility were excluded from analyses (N=1,250). Data were weighted to represent the study-eligible population. MAIN OUTCOME MEASURE Healthy Eating Index 2015 scores of children at age 24 months were calculated based on 24-hour dietary recalls. STATISTICAL ANALYSES PERFORMED Unadjusted analysis of variance examined Healthy Eating Index 2015 scores by WIC participation duration. Multivariate linear regression analysis tested independent effects of WIC duration on Healthy Eating Index 2015 total scores, controlling for sociodemographic factors. RESULTS After controlling for covariates, WIC participation duration was significantly associated with diet quality. Children in the high duration group had significantly higher Healthy Eating Index 2015 total scores (adjusted mean 59.3, 95% CI 58.6 to 60.1) than children in the low duration group (adjusted mean 55.3, 95% CI 51.6 to 59.0) (P=0.035). CONCLUSIONS Children who received WIC benefits during most of the first 2 years of life had better diet quality at age 24 months than children who, despite remaining eligible for benefits, discontinued WIC benefits during infancy. Findings suggest nutritional benefits for eligible children who stay in the program longer.

中文翻译：

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更长时间参与 WIC 与 24 个月大的儿童更好的饮食质量有关

背景 对于妇女、婴儿和儿童特殊补充营养计划 (WIC) 的暴露持续时间与儿童饮食质量的关系知之甚少。目的 本研究的目的是检查 WIC 参与持续时间与 24 个月大儿童饮食质量之间的关联。设计 对 2013 年最初参加 WIC 的参与者进行了一项全国纵向观察研究。对 2013 年至 2016 年的研究母亲进行了电话访谈。WIC 参与的持续时间根据访谈次数分为高、中或低。参与者报告获得了 WIC 福利。参与者 已完成基线访谈和 24 个月内所有访谈的 WIC 婴幼儿喂养实践研究 2 的参与者；报告因认为计划不合格而停止 WIC 的参与者被排除在分析之外（N = 1,250）。对数据进行加权以代表符合研究的人群。主要结果测量健康饮食指数 24 个月大儿童的 2015 年分数是根据 24 小时饮食回忆计算得出的。执行的统计分析 未经调整的方差分析按 WIC 参与持续时间检查了 2015 年健康饮食指数得分。多变量线性回归分析测试了 WIC 持续时间对 2015 年健康饮食指数总分的独立影响，控制了社会人口因素。结果 控制协变量后，WIC 参与持续时间与饮食质量显着相关。高持续时间组儿童的 2015 年健康饮食指数总分明显更高（调整后平均为 59.3，95% CI 58.6 至 60.1）比低持续时间组的儿童（调整后平均 55.3，95% CI 51.6 至 59.0）（P = 0.035）。结论 在生命最初 2 年的大部分时间里获得 WIC 福利的儿童在 24 个月大时的饮食质量比尽管仍有资格获得福利但在婴儿期停止 WIC 福利的儿童更好。调查结果表明，符合条件的儿童在该计划中停留时间更长的营养益处。