کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5857782 | 1562132 | 2010 | 6 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Statistical power in the analyses of brain weight measures in pesticide neurotoxicity testing and the relationship between brain and body weight
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کلمات کلیدی
موضوعات مرتبط
علوم زیستی و بیوفناوری
علوم محیط زیست
بهداشت، سم شناسی و جهش زایی
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Statistical power in the analyses of brain weight measures in pesticide neurotoxicity testing and the relationship between brain and body weight Statistical power in the analyses of brain weight measures in pesticide neurotoxicity testing and the relationship between brain and body weight](/preview/png/5857782.png)
چکیده انگلیسی
Few investigations have examined statistical power in studies of pesticide exposure effects on rat brain weight. Using data from developmental neurotoxicity studies conducted by four different laboratories, we evaluated statistical power to detect changes in rat brain weight and examined the relationship between brain and body weight in several age groups. All power calculations assumed an alpha value of 0.05, equal variance between groups, and a sample size of 10/group. Statistical power often varied substantially both within and between laboratories, and for a 5% change in brain weight average between-laboratory differences in power were as large as 34%. Power estimates for individual studies often spanned a range of more than 50% within a given laboratory. The likelihood of detecting a “significant” change smaller than 5% was generally low for all laboratories. Brain weight increased linearly with body weight within age groups but the strength of this relationship decreased with age. Therefore, confounding by body weight may be more likely in brain weight analyses for younger animals. Our findings suggest that caution is required when weighing the importance of statistical “significance” in studies of pesticide exposure effects on brain weight as the power to detect these differences may be low.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Regulatory Toxicology and Pharmacology - Volume 57, Issues 2â3, JulyâAugust 2010, Pages 235-240
Journal: Regulatory Toxicology and Pharmacology - Volume 57, Issues 2â3, JulyâAugust 2010, Pages 235-240
نویسندگان
Scott Weichenthal, Scott Hancock, Kathleen Raffaele,