Best (but oft-forgotten) practices: sample size and power calculation for a dietary intervention trial with episodically consumed foods
文献类型：期刊论文
| 作者 | Zhang, Wei1; Liu, Aiyi2; Zhang, Zhiwei3; Nansel, Tonja4; Halabi, Susan5 |
| 刊名 | AMERICAN JOURNAL OF CLINICAL NUTRITION
 |
| 出版日期 | 2020-10-01 |
| 卷号 | 112期号:4页码:920-925 |
| 关键词 | dietary intervention trials episodic consumption power sample size type I error |
| ISSN号 | 0002-9165 |
| DOI | 10.1093/ajcn/nqaa176 |
| 英文摘要 | Dietary interventions often target foods that are underconsumed relative to dietary guidelines, such as vegetables, fruits, and whole grains. Because these foods are only consumed episodically for some participants, data from such a study often contains a disproportionally large number of zeros due to study participants who do not consume any of the target foods on the days that dietary intake is assessed, thus generating semicontinuous data. These zeros need to be properly accounted for when calculating sample sizes to ensure that the study is adequately powered to detect a meaningful intervention effect size. Nonetheless, this issue has not been well addressed in the literature. Instead, methods that are common for continuous outcomes are typically used to compute the sample sizes, resulting in a substantially under- or overpowered study. We propose proper approaches to calculating the sample size needed for dietary intervention studies that target episodically consumed foods. Sample size formulae are derived for detecting the mean difference in the amount of intake of an episodically consumed food between an intervention and a control group. Numerical studies are conducted to investigate the accuracy of the sample size formulae as compared with the ad hoc methods. The simulation results show that the proposed formulae are appropriate for estimating the sample sizes needed to achieve the desired power for the study. The proposed method for sample size is recommended for designing dietary intervention studies targeting episodically consumed foods. |
| 资助项目 | Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) |
| WOS研究方向 | Nutrition & Dietetics |
| 语种 | 英语 |
| WOS记录号 | WOS:000581138300008 |
| 出版者 | OXFORD UNIV PRESS |
| 源URL | [http://ir.amss.ac.cn/handle/2S8OKBNM/52418]  |
| 专题 | 中国科学院数学与系统科学研究院 |
| 通讯作者 | Liu, Aiyi |
| 作者单位 | 1.Chinese Acad Sci, Acad Math & Syst Sci, Beijing, Peoples R China 2.Eunice Kennedy Shriver Natl Inst Child Hlth & Hum, Biostat & Bioinformat Branch, NIH, Bethesda, MD 20892 USA 3.NCI, Biostat Branch, Div Canc Treatment & Diagnost, NIH, Bethesda, MD 20892 USA 4.Eunice Kennedy Shriver Natl Inst Child Hlth & Hum, Social & Behav Sci Branch, NIH, Bethesda, MD USA 5.Duke Univ, Dept Biostat & Bioinformat, Durham, NC USA |
| 推荐引用方式 GB/T 7714 | Zhang, Wei,Liu, Aiyi,Zhang, Zhiwei,et al. Best (but oft-forgotten) practices: sample size and power calculation for a dietary intervention trial with episodically consumed foods[J]. AMERICAN JOURNAL OF CLINICAL NUTRITION,2020,112(4):920-925. |
| APA | Zhang, Wei,Liu, Aiyi,Zhang, Zhiwei,Nansel, Tonja,&Halabi, Susan.(2020).Best (but oft-forgotten) practices: sample size and power calculation for a dietary intervention trial with episodically consumed foods.AMERICAN JOURNAL OF CLINICAL NUTRITION,112(4),920-925. |
| MLA | Zhang, Wei,et al."Best (but oft-forgotten) practices: sample size and power calculation for a dietary intervention trial with episodically consumed foods".AMERICAN JOURNAL OF CLINICAL NUTRITION 112.4(2020):920-925. |
入库方式： OAI收割
来源：数学与系统科学研究院
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。