Spiers P S, Lohmann R, Guntheroth W G
Department of Pediatrics, University of Washington School of Medicine, Seattle 98195.
J Paediatr Child Health. 1993 Jun;29(3):215-8. doi: 10.1111/j.1440-1754.1993.tb00490.x.
The risk of SIDS has been reported consistently as being positively related to parity or birth order. However, the reports in question have failed to take into account the possible confounding effects of sibship size. In the present study it was reasoned that if this were done the relationship would be negative, not positive. In an analysis of births stratified by sibship size positive. In an analysis of births stratified by sibship size occurring in the years 1975-84 in the state of Oregon, it was found that the risk of SIDS in the age range 7-364 days did indeed tend to decrease with increasing birth order when sibship size was held constant. An expected tendency for SIDS rates to increase with increasing sibship size when birth order was held constant was also confirmed. This tendency is probably explained by a negative correlation between family size and socio-economic status. Non-SIDS rates behaved in a similar manner to SIDS rates. The tendency for the risk of SIDS to decrease with increasing birth order was more evident when births following a pregnancy interval of less than 12 months were excluded.
婴儿猝死综合征（SIDS）的风险一直被报告与产次或出生顺序呈正相关。然而，相关报告并未考虑同胞数量可能产生的混杂效应。在本研究中，我们推断如果考虑这一因素，这种关系将是负相关，而非正相关。在对俄勒冈州1975年至1984年间按同胞数量分层的出生情况进行分析时发现，当同胞数量保持不变时，7至364天龄婴儿猝死综合征的风险确实会随着出生顺序的增加而降低。同时也证实了，当出生顺序保持不变时，婴儿猝死综合征的发生率有随同胞数量增加而上升的预期趋势。这种趋势可能是由家庭规模与社会经济地位之间的负相关关系所解释的。非婴儿猝死综合征的发生率与婴儿猝死综合征的发生率表现相似。当排除妊娠间隔小于12个月后的出生情况时，婴儿猝死综合征风险随出生顺序增加而降低的趋势更为明显。
