The results indicated that only flood severity had a statistically significant effect on public health problems (p < .05), both directly and indirectly, as also reported in several studies [34, 35]. The more disastrous a flood situation becomes, the more serious the public health problems will be. On the other hand, if flood situations are less disastrous, the public health problems are also less serious. During severe floods, many issues can occur, such as food and water scarcity, consumption of contaminated food and water, unsanitary excretion, flooded houses, power outage, poisonous animals in floodwater, insects carrying diseases from floodwater, and communication outages. These issues can lead to public health problems, including malnutrition from food and water scarcity, poisoning and water-borne diseases from consuming contaminated food and water, water-borne diseases due to water contamination from unsanitary excretion, contagious diseases transmitted from poisonous animals and insects in floodwater, drowning because of the high level of floodwater level, injuries from uncontrolled electrical currents, accidents in the dark due to power outages, and mental health problems from a lack of communication with the outside world. Mental health problems encountered during floods include stress, panic, and fear; moreover, mental health problems such as depression persist even after floods. As indicated by the results, mental health problems differed from other problems, as mental health problems were not present during floods in the Loei River Basin. Since the mass of floodwater quickly flowed into the Mekong River, the duration of each flood in the basin usually lasted no more than 2 days; subsequently, mental health was not yet affected by floods.
Help had a direct inverse effect on public health problems, which was supported by previous studies [36, 37]. When there was a great deal of help, the number of public health problems was lower. In contrast, if help was limited, public health problems became more serious. Help could clearly relieve public health problems. For instance, food and water aid can decrease the risks of malnutrition, food and water poisoning, and infections of diseases from food and water because the donated food and water were prepared and brought in from outside the affected area and hence were not contaminated with floodwater. Rescuing and moving people, patients, and their belongings out of the affected area ensured that they would be safe from the source of public health problems. Rescued and transferred patients could also receive the care they needed immediately. Saving victims’ possessions reduces the loss of property, which can also lower the chances of mental health issues. In addition, using public relations to keep those affected informed can help them be aware of possible harms from floods, resulting in fewer public health issues.
Preparation had both direct and indirect inverse impacts on public health problems, as concluded in other studies [38, 39]. Public health problems were less common when there was more preparation. On the other hand, public health problems were more severe when preparation was insufficient. Preparedness could directly reduce public health problems. For instance, if food and water were stored in advance, there would not be a shortage of food and water during a flood. The indirect impact of preparation involved help. If the aid plan were well prepared, rescue would be prompt in case of emergency. According to the results, the direct impact had a minimal value because preparation primarily led to the indirect impact in the form of help. During a flood disaster, good preparedness plays a crucial role in providing sufficient and effective assistance that can reduce public health problems.
Although help and preparation directly and indirectly affected public health problems, they did not have a statistically significant effect. The standardized factor loading is very low, which may indicate that factors other than flood severity, help and preparation could affect the occurrence of public health problems, which is an interesting point for future study. However, the observed variable, which is a component of all latent variables including the public health problem latent variable, flood severity latent variable, preparation latent variable, and help latent variable, was statistically significant (p < .05). Therefore, the addition of latent variables from the existing study may enhance the predictive ability and statistical significance of future studies.
In terms of using a developed application to simulate situations of public health problems during floods, there has been a multitude of studies simulating flood situations [26,27,28, 39]. In this study, GIS and SEM techniques were used to combine values for public health problem simulation. The advantage of SEM over the regression equation is that SEM considers latent variables with observed variables as a factor, whereas regression equations examine only observed variables measured by collecting data. Another advantage of SEM with path analysis is that it calculates not only direct but also indirect effects, resulting in a more elaborate consideration of effects. In contrast, the regression equation examines only the direct effect. Furthermore, the incorporation of GIS with SEM allows the mapping arrangement to be visualized, supporting more convenient and efficient management of public health problems at both the provincial and subdistrict levels. Nonetheless, some issues were not considered in this study, and the predictive ability was only 7.7%, probably due to the high complexity of public health issues. Nonetheless, this research provides a good starting point for further study and development to clarify, manage, and solve public health problems. A more diverse study of related variables could be developed in future research, which would likely increase the model’s predictive ability.
Management to address the three latent variables affecting public health problems—flood severity, preparation and help—could be practically implemented. Water management through river dams and the tributary reservoirs surrounding the province that connect with the Loei River should be considered to reduce flood severity. Preparation in terms of both budget and manpower, including various equipment that supports the provision of emergency assistance, should also be considered. In providing help for flood incidents, budget and manpower must be managed, directed, and facilitated effectively across all sectors, including government agencies, the private sector, and the people, who must work together vigorously with dedication and full efficiency.
The simulation model of public health problems during a flood can be implemented at both the technical and policy levels in different areas of Thailand. Questionnaires can be collected in a given area, and simulations of public health problems in a flood situation within that area can then be projected based on questionnaire data. Following simulation, area situation data can be used for preparation planning, assistance, and fixing flood-related problems that arise in that area.
Since the simulation system for public health problem situations was developed using cross-sectional data, the accuracy of the predictions could not be evaluated due to the lack of data for comparison. Therefore, in future studies, longitudinal data should be consecutively collected for at least 2 years for comparison to examine the prediction accuracy of the simulation system.