London School of Hygiene and Tropical Medicine, London, UK.
Trop Med Int Health. 2012 Jun;17(6):684-93. doi: 10.1111/j.1365-3156.2012.02987.x.
To review methods for the statistical analysis of parasite and other skewed count data.
Statistical methods for skewed count data are described and compared, with reference to a 10-year period of Tropical Medicine and International Health (TMIH). Two parasitological datasets are used for illustration.
The review of TMIH found 90 articles, of which 89 used descriptive methods and 60 used inferential analysis. A lack of clarity is noted in identifying the measures of location, in particular the Williams and geometric means. The different measures are compared, emphasising the legitimacy of the arithmetic mean for the skewed data. In the published articles, the t test and related methods were often used on untransformed data, which is likely to be invalid. Several approaches to inferential analysis are described, emphasising (1) non-parametric methods, while noting that they are not simply comparisons of medians, and (2) generalised linear modelling, in particular with the negative binomial distribution. Additional methods, such as the bootstrap, with potential for greater use are described.
Clarity is recommended when describing transformations and measures of location. It is suggested that non-parametric methods and generalised linear models are likely to be sufficient for most analyses.
综述寄生虫和其他偏态计数数据的统计分析方法。
描述并比较了偏态计数数据的统计方法，并参考了热带医学与国际卫生杂志（TMIH）十年期间的数据。使用两个寄生虫数据集进行说明。
对 TMIH 的回顾发现了 90 篇文章，其中 89 篇使用描述性方法，60 篇使用推断性分析。注意到在确定位置度量，特别是威廉姆斯和几何平均值时，存在不明确性。比较了不同的度量方法，强调了算术平均值对于偏态数据的合理性。在已发表的文章中，t 检验和相关方法通常用于未经转换的数据，这可能是无效的。描述了几种推断性分析方法，强调（1）非参数方法，同时注意到它们不仅仅是中位数的比较，以及（2）广义线性模型，特别是负二项式分布。还描述了其他方法，如具有更大应用潜力的自举法。
建议在描述转换和位置度量时要明确。建议非参数方法和广义线性模型可能足以进行大多数分析。
