Frank Batten School of Leadership and Public Policy, University of Virginia, Charlottesville.
National Bureau of Economic Research, Cambridge, Massachusetts.
JAMA Health Forum. 2024 Jul 5;5(7):e242006. doi: 10.1001/jamahealthforum.2024.2006.
Despite considerable prior research, it remains unclear whether and by how much state COVID-19-related restrictions affected the number of pandemic deaths in the US.
To determine how state restrictions were associated with excess COVID-19 deaths over a 2-year analysis period.
DESIGN, SETTING, AND PARTICIPANTS: This was a cross-sectional study using state-level mortality and population data from the US Centers for Disease Control and Prevention for 2020 to 2022 compared with baseline data for 2017 to 2019. Data included the total US population, with separate estimates for younger than 45 years, 45 to 64 years, 65 to 84 years, and 85 years or older used to construct age-standardized measures. Age-standardized excess mortality rates and ratios for July 2020 to June 2022 were calculated and compared with prepandemic baseline rates. Excess death rates and ratios were then regressed on single or multiple restrictions, while controlling for excess death rates or ratios, from March 2020 to June 2020. Estimated values of the dependent variables were calculated for packages of weak vs strong state restrictions. Behavioral changes were investigated as a potential mechanism for the overall effects. Data analyses were performed from October 1, 2023, to June 13, 2024.
Age and cause of death.
Excess deaths, age-standardized excess death rates per 100 000, and excess death ratios.
Mask requirements and vaccine mandates were negatively associated with excess deaths, prohibitions on vaccine or mask mandates were positively associated with death rates, and activity limitations were mostly not associated with death rates. If all states had imposed restrictions similar to those used in the 10 most restrictive states, excess deaths would have been an estimated 10% to 21% lower than the 1.18 million that actually occurred during the 2-year analysis period; conversely, the estimates suggest counterfactual increases of 13% to 17% if all states had restrictions similar to those in the 10 least-restrictive states. The estimated strong vs weak state restriction difference was 271 000 to 447 000 deaths, with behavior changes associated with 49% to 79% of the overall disparity.
This cross-sectional study indicates that stringent COVID-19 restrictions, as a group, were associated with substantial decreases in pandemic mortality, with behavior changes plausibly serving as an important explanatory mechanism. These findings do not support the views that COVID-19 restrictions were ineffective. However, not all restrictions were equally effective; some, such as school closings, likely provided minimal benefit while imposing substantial cost.
尽管先前进行了大量研究，但仍不清楚美国的州 COVID-19 相关限制措施是否以及在多大程度上影响了大流行期间的死亡人数。
确定在两年的分析期间，州限制措施与 COVID-19 死亡人数的超额情况之间的关系。
设计、地点和参与者：这是一项使用美国疾病控制与预防中心的州级死亡率和人口数据进行的横断面研究，时间范围为 2020 年至 2022 年，与 2017 年至 2019 年的基线数据进行比较。数据包括美国总人口，对于年龄在 45 岁以下、45 至 64 岁、65 至 84 岁和 85 岁或以上的人群，分别使用构建年龄标准化指标。计算了 2020 年 7 月至 2022 年 6 月的年龄标准化超额死亡率和比率，并与大流行前的基线比率进行了比较。然后，在控制 2020 年 3 月至 6 月的超额死亡率或比率的情况下，对单一或多种限制措施进行回归分析。估计了弱限制和强限制州措施的因变量值。调查了行为变化作为整体影响的潜在机制。数据分析于 2023 年 10 月 1 日至 2024 年 6 月 13 日进行。
年龄和死因。
超额死亡人数、每 10 万人的年龄标准化超额死亡率和超额死亡率比率。
口罩要求和疫苗授权与超额死亡人数呈负相关，疫苗或口罩授权禁令与死亡率呈正相关，活动限制与死亡率相关性不大。如果所有州都实施了类似于 10 个最严格州实施的限制措施，那么在两年的分析期间，超额死亡人数估计将减少 10%至 21%；相反，如果所有州都实施了类似于 10 个限制最宽松的州实施的限制措施，那么估计将增加 13%至 17%。估计的强限制和弱限制州之间的差异为 271000 至 447000 人死亡，行为变化可能解释了整体差异的 49%至 79%。
这项横断面研究表明，严格的 COVID-19 限制措施作为一个整体，与大流行期间的死亡率大幅下降有关，行为变化可能是一个重要的解释机制。这些发现并不支持 COVID-19 限制措施无效的观点。然而，并非所有限制措施都同样有效；一些限制措施，如学校关闭，可能带来的好处很小，而造成的成本却很大。
