We have read with great interest the recent study by Meer et al on novel methods to identify risk factors for psoriatic arthritis (PsA), psoriasis, rheumatoid arthritis (RA), and ankylosing spondylitis.1 In that article, we appreciate that age, sex, BMI (calculated as weight in kilograms divided by height in meters squared), and time observed between the experimental group and control group were highly matched. However, we have a few suggestions to strengthen the conclusions in the study of Meer et al.

中文翻译：

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抽样偏差是否应该归咎于风湿性疾病之间的明显关联？

我们饶有兴趣地阅读了 Meer 等人最近的一项研究，该研究涉及确定银屑病关节炎 (PsA)、银屑病、类风湿性关节炎 (RA) 和强直性脊柱炎的危险因素的新方法。1在那篇文章中，我们认识到年龄、性别、BMI（计算为体重（千克）除以身高（米）的平方），以及实验组和对照组之间观察到的时间高度匹配。但是，我们有一些建议可以加强 Meer 等人研究中的结论。