BackgroundWhen unaddressed, contamination in child maltreatment research, in which some proportion of children recruited for a nonmaltreated comparison group are exposed to maltreatment, downwardly biases the significance and magnitude of effect size estimates. This study extends previous contamination research by investigating how a dual‐measurement strategy of detecting and controlling contamination impacts causal effect size estimates of child behavior problems.MethodsThis study included 634 children from the LONGSCAN study with 63 cases of confirmed child maltreatment after age 8 and 571 cases without confirmed child maltreatment. Confirmed child maltreatment and internalizing and externalizing behaviors were recorded every 2 years between ages 4 and 16. Contamination in the nonmaltreated comparison group was identified and controlled by either a prospective self‐report assessment at ages 12, 14, and 16 or by a one‐time retrospective self‐report assessment at age 18. Synthetic control methods were used to establish causal effects and quantify the impact of contamination when it was not controlled, when it was controlled for by prospective self‐reports, and when it was controlled for by retrospective self‐reports.ResultsRates of contamination ranged from 62% to 67%. Without controlling for contamination, causal effect size estimates for internalizing behaviors were not statistically significant. Causal effects only became statistically significant after controlling contamination identified from either prospective or retrospective reports and effect sizes increased by between 17% and 54%. Controlling contamination had a smaller impact on effect size increases for externalizing behaviors but did produce a statistically significant overall effect, relative to the model ignoring contamination, when prospective methods were used.ConclusionsThe presence of contamination in a nonmaltreated comparison group can underestimate the magnitude and statistical significance of causal effect size estimates, especially when investigating internalizing behavior problems. Addressing contamination can facilitate the replication of results across studies.

中文翻译：

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评估儿童虐待对青少年内化和外化行为问题因果影响的污染偏差

背景如果不解决儿童虐待研究中的污染问题，即为非虐待对照组招募的一定比例的儿童遭受虐待，就会使效应大小估计的显着性和幅度产生向下偏差。本研究通过调查检测和控制污染的双重测量策略如何影响儿童行为问题的因果效应大小估计，扩展了之前的污染研究。方法本研究纳入了 LONGSCAN 研究中的 634 名儿童，其中 63 例确诊为 8 岁后虐待儿童，571 例未经证实的虐待儿童案件。在 4 岁至 16 岁之间，每两年记录一次已确认的儿童虐待以及内化和外化行为。未受虐待的对照组中的污染是通过 12、14 和 16 岁时的前瞻性自我报告评估或通过单次评估来识别和控制的。 18 岁时进行回顾性自我报告评估。综合控制方法用于确定因果效应，并量化污染在不受控制、通过前瞻性自我报告控制以及通过回顾性控制时的影响自我报告。结果污染率从 62% 到 67% 不等。在不控制污染的情况下，内化行为的因果效应大小估计不具有统计显着性。仅在控制了前瞻性或回顾性报告中确定的污染后，因果效应才变得具有统计学意义，并且效应大小增加了 17% 至 54%。当使用前瞻性方法时，控制污染对外化行为的效应大小增加的影响较小，但相对于忽略污染的模型，确实产生了统计上显着的总体效应。 结论因果效应大小估计的重要性，特别是在调查内化行为问题时。解决污染问题可以促进研究结果的复制。