1936 - 1984年丹麦双胞胎出生率的季节性变化。
Seasonality in twin birth rates, Denmark, 1936-84.
作者信息
Bonnelykke B, Søgaard J, Nielsen J
机构信息
Cytogenetic Laboratory, Arhus Psychiatric Hospital, Denmark.
出版信息
J Epidemiol Community Health. 1987 Dec;41(4):338-43. doi: 10.1136/jech.41.4.338.
A study was made of seasonality in twin birth rate in Denmark between 1977 and 1984. We studied all twin births (N = 45,550) in all deliveries (N = 3,679,932) during that period. Statistical analysis using a simple harmonic sinusoidal model provided no evidence for seasonality. However, sequential polynomial analysis disclosed a significant fit to a fifth order polynomial curve with peaks in twin birth rates in May-June and December, along with troughs in February and September. A falling trend in twinning rate broke off in Denmark around 1970, and from 1970 to 1984 an increasing trend was found. The results are discussed in terms of possible environmental influences on twinning.
对1977年至1984年间丹麦双胞胎出生率的季节性进行了一项研究。我们研究了该时期所有分娩（N = 3,679,932）中的所有双胞胎出生情况（N = 45,550）。使用简单谐波正弦模型的统计分析未发现季节性证据。然而，序列多项式分析显示与五阶多项式曲线有显著拟合，双胞胎出生率在5月至6月和12月出现峰值，2月和9月出现谷值。丹麦的双胞胎出生率下降趋势在1970年左右中断，1970年至1984年呈现上升趋势。从双胞胎可能受到的环境影响方面对结果进行了讨论。
Zotero 插件