Analysis of health effects of the “Internet + Rural-urban water supply” model of the Ningxia Xihaigu Region

The evaluation of the effect of rural drinking water safety policy is an important issue in the field of rural revitalization， water security and public health. In order to accurately identify the health effects of water supply projects and related policy implementation， this paper takes Xihaigu region of Ningxia as a case study， focusing on the implementation of rural-urban drinking water safety projects in central and southern Ningxia and the benefit of the application of "Internet + rural-urban water supply" Pengyang model. The difference-in-differences （DID） model was used for quantitative evaluation， and the experimental group， control group and analysis period are carefully selected. Based on the county-level panel data of Ningxia from 2013 to 2019， the average mortality rate of the region was selected as the explanatory variable. A model framework including multi-dimensional control variables such as population， economy， environment， education and medical care was constructed， and the robustness of the results of the benchmark regression scheme was verified by dynamic effect test， placebo test and other methods. The empirical research shows that the rural-urban water supply project and related policy intervention brought about a significant decrease in the mortality rate of residents in the beneficiary counties （districts） by 0.75 ‰ on average compared with other counties （districts） in Xihaigu， and the policy effect can positively influence outcomes for 4-5 years. The contribution of rural-urban water supply policy intervention to the reduction of mortality in Xihaigu region is only slightly smaller than the effects of per capita local public financial expenditure and the proportion of Han population， and greater than the effects of other variables such as the number of practicing physicians per thousand population and the primary school graduation rate. It was identified as a key driver significantly affecting residents' health. The evaluation results provide an empirical basis for the analysis of the effects of similar water supply policies， and provide strong support for scientific decision-making on the high-quality development of rural water supply.