State-level child welfare policies and practices affect what can be referred, investigated, and substantiated as child maltreatment, and these institutional factors vary across states and over time. Researchers typically have not accounted for these factors in analyses, confounding institutional features with the underlying construct they seek to study. The present study addresses this limitation by demonstrating how changes in specific state child welfare policies and practices influence reported and substantiated maltreatment in the National Child Abuse and Neglect Data System (NCANDS). Using negative binomial models with state and year fixed-effects to analyze data from 2005 to 2018, we found significant influence of state policy and practice changes on state-level rates of reported and substantiated maltreatment over time. If a state implemented three of the most common policy changes—adding mandated reporters, centralized intake, and staff—its maltreatment reports were an estimated 32% higher than they would have been in the absence of these changes. By contrast, most state policy changes decreased the number of reports that were substantiated—by 24% if they implemented both differential response and higher standards of proof. Implications for future research and policy are discussed.

州一级的儿童福利政策和实践会影响可以被称为、调查和证实为虐待儿童的内容，这些制度因素因州和时间而异。研究人员通常没有在分析中考虑这些因素，将制度特征与他们试图研究的基本结构混淆了。本研究通过展示特定州儿童福利政策和做法的变化如何影响国家虐待和忽视儿童数据系统 (NCANDS) 中报告和证实的虐待行为来解决这一限制。使用具有州和年份固定效应的负二项式模型分析 2005 年至 2018 年的数据，我们发现随着时间的推移，州政策和实践的变化对州一级报告和证实的虐待率有显着影响。如果一个州实施了三个最常见的政策变化——增加授权记者、集中接收和工作人员——其虐待报告估计比没有这些变化的情况下高 32%。相比之下，大多数州政策变化减少了得到证实的报告数量——如果它们同时实施差异化响应和更高的证明标准，则减少了 24%。讨论了对未来研究和政策的影响。大多数州政策变化都减少了得到证实的报告数量——如果它们同时实施差异响应和更高的证明标准，则减少了 24%。讨论了对未来研究和政策的影响。大多数州政策变化都减少了得到证实的报告数量——如果它们同时实施差异响应和更高的证明标准，则减少了 24%。讨论了对未来研究和政策的影响。