Department of Dental Hygiene, Yonsei University, Wonju College of Medicine.
Department of Social and Behavioral Sciences, Harvard T.H. Chan School of Public Health.
J Epidemiol. 2022 May 5;32(5):215-220. doi: 10.2188/jea.JE20200417. Epub 2021 Jul 10.
In 2012, the Korean National Health Insurance extended its coverage to include denture services for older adults. We examined whether the new policy resulted in improved chewing ability in the eligible population.
We used interrupted time-series (ITS) analysis, a quasi-experimental design, to analyze the effect of the policy. We used data from the Korea National Health and Nutrition Examination Survey conducted from 2007 to 2016-2018. The study population consisted of two groups: the treatment group, aged 65 years or older and eligible for the dental insurance benefit; and the control group, those younger than 65 years and ineligible. The main evaluated outcome was self-reported chewing difficulty.
The ITS analysis showed that chewing difficulty decreased annually by 0.93% (95% CI, -1.30 to -0.55%) and 0.38% (95% CI, -0.59 to -0.16%) after the policy extension in the older than 65 and younger than 65 groups, respectively. However, we could not conclude that the insurance extension affected chewing difficulty because there was a decrease in the control group as well.
Chewing ability improved in both older and younger adults regardless of dental insurance coverage for older adults. Other exogenous factors probably led to the improvements in chewing ability as well as dental insurance benefits.
2012 年，韩国国家健康保险将其覆盖范围扩大到包括老年人的义齿服务。我们研究了新政策是否使符合条件的人群的咀嚼能力得到改善。
我们使用中断时间序列（ITS）分析，一种准实验设计，来分析该政策的效果。我们使用了 2007 年至 2016-2018 年期间进行的韩国国家健康和营养检查调查的数据。研究人群包括两组：治疗组，年龄在 65 岁或以上，有资格享受牙科保险福利；对照组，年龄在 65 岁以下，无资格享受。主要评估结果是自我报告的咀嚼困难程度。
ITS 分析显示，在政策扩大后，65 岁以上组和 65 岁以下组的咀嚼困难程度分别每年下降 0.93%（95%CI，-1.30 至-0.55%）和 0.38%（95%CI，-0.59 至-0.16%）。然而，我们不能得出保险扩展影响咀嚼困难的结论，因为对照组也出现了下降。
无论老年人的牙科保险覆盖范围如何，老年人和年轻人的咀嚼能力都有所提高。其他外生因素可能也导致了咀嚼能力的提高以及牙科保险福利的改善。
