ObjectiveThis nested case-control study, based on the Shanghai Birth Cohort (SBC), aimed to explore the impact of early pregnancy exposure to organophosphorus flame retardants (OPFRs) on attention deficit hyperactive disorder (ADHD)-like symptoms in 4-year-old children, so as to provide epidemiological evidence regarding the health effects of emerging contaminant OPFRs in children. MethodsStrengths and Difficulties Questionnaire (SDQ) was used to assess ADHD like symptoms in 4-year-old children. Children with an SDQ hyperactivity subscale score ≥6 points were defined as cases, while those with a score <5 points were considered as controls. The case and control groups were matched at 1∶1 based on the child’s age (±6 months), sex, and parental or primary caregiver’s education level. A total of 105 cases and 112 controls were included eventually. Concentrations of eight OPFRs metabolites in early pregnancy urine samples were measured using ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS), including di-phenyl phosphate (DPHP), di-m-cresylphosphate (DmCP), di-o-cresylphosphate (DoCP), di-p-cresylphosphate (DpCP), di-n-butyl phosphate (DnBP), di-iso-butyl phosphate (DiBP), bis(2-butoxyethyl) phosphate (BBOEP), and bis(2-ethylhexyl) phosphate (BEHP). Basic demographic information of mothers and children were collected through questionnaire surveys and medical records extraction. Binary logistic regression models were used to analyze the effect of individual OPFRs exposure during early pregnancy on ADHD-like symptoms, while a quantile g-computation (Qgcomp) regression model was employed to assess the effects of mixed OPFRs exposure (with detection rates >75%) on ADHD-like symptoms in 4-year-old children. ResultsIn this study, the detection rates of DPHP, DoCP, and the DmCP&DpCP in the urine of early pregnancy women were higher than 75%, with DPHP having the highest detection rate (86.18%). The median concentrations of DPHP were highest in both the case and control groups (0.396 μg·L^-1 and 0.305 μg·L^-1, respectively). Binary logistic regression analyses revealed that exposure to DPHP during early pregnancy increased the risk of ADHD-like symptoms in 4-year-old children (OR=1.262, 95%CI: 1.017‒1.565). The mixed exposure model analyses showed that early pregnancy co-exposure to OPFRs increased the risk of ADHD-like symptoms (OR=1.508, 95%CI: 1.012‒2.258), with DPHP being the primary contributor to the association. ConclusionEarly pregnancy exposure to DPHP is positively associated with an increased risk of ADHD-like symptoms in 4-year-old children. Additionally, DPHP contributed the most to the adverse effects of mixed OPFRs exposure on ADHD-like symptoms. However, these findings require further validation through other large-scale prospective cohort studies.

Objective To clarify the interaction among the interests and strategic choices of multiple subjects of medical insurance for the older people in China,and to provide a decision-making basis for the improvement of medical insurance policy for the older people.Methods An evolutionary game model was constructed based on evolutionary game theory and its steady state was simulated using Matlab R2021b software for the health insurer,the health care provider and the elderly.Results There is a conflict of interest between health insurance providers,healthcare providers and older people when all three parties consider maximising their own utility.In order to reach an evolutionary equilibrium,the strategic choice of the health insurance provider is to take"cost-cutting"behaviour to control the expenditure of the health insurance fund;the strategic choice of the older people is to increase the use of medical services to meet the demand for medical services;and the strategic choice of the medical service provider is related to the quantitative relationship between the reimbursement ratio of the health insurance and the cost ratio of medical services.When the reimbursement rate is 0.95,the probability that the provider will choose rational behaviour to control health care expenditure is the highest.Conclusion Healthcare providers with higher reimbursement rates have a higher probability of choosing rational behaviour.At the same time,the medical insurance reimbursement ratio cannot be raised blindly.It is recommended that the level of health insurance benefits be reasonably adjusted,the construction of a differentiation of the reimbursement ratio of medical insurance should be improved,and the measures for the management of medical behaviors should be enhanced,so as to effectively meet the health needs of the elderly population while at the same time guaranteeing medical safety.

Objective To clarify the interaction among the interests and strategic choices of multiple subjects of medical insurance for the older people in China,and to provide a decision-making basis for the improvement of medical insurance policy for the older people.Methods An evolutionary game model was constructed based on evolutionary game theory and its steady state was simulated using Matlab R2021b software for the health insurer,the health care provider and the elderly.Results There is a conflict of interest between health insurance providers,healthcare providers and older people when all three parties consider maximising their own utility.In order to reach an evolutionary equilibrium,the strategic choice of the health insurance provider is to take"cost-cutting"behaviour to control the expenditure of the health insurance fund;the strategic choice of the older people is to increase the use of medical services to meet the demand for medical services;and the strategic choice of the medical service provider is related to the quantitative relationship between the reimbursement ratio of the health insurance and the cost ratio of medical services.When the reimbursement rate is 0.95,the probability that the provider will choose rational behaviour to control health care expenditure is the highest.Conclusion Healthcare providers with higher reimbursement rates have a higher probability of choosing rational behaviour.At the same time,the medical insurance reimbursement ratio cannot be raised blindly.It is recommended that the level of health insurance benefits be reasonably adjusted,the construction of a differentiation of the reimbursement ratio of medical insurance should be improved,and the measures for the management of medical behaviors should be enhanced,so as to effectively meet the health needs of the elderly population while at the same time guaranteeing medical safety.

Objective To clarify the interaction among the interests and strategic choices of multiple subjects of medical insurance for the older people in China,and to provide a decision-making basis for the improvement of medical insurance policy for the older people.Methods An evolutionary game model was constructed based on evolutionary game theory and its steady state was simulated using Matlab R2021b software for the health insurer,the health care provider and the elderly.Results There is a conflict of interest between health insurance providers,healthcare providers and older people when all three parties consider maximising their own utility.In order to reach an evolutionary equilibrium,the strategic choice of the health insurance provider is to take"cost-cutting"behaviour to control the expenditure of the health insurance fund;the strategic choice of the older people is to increase the use of medical services to meet the demand for medical services;and the strategic choice of the medical service provider is related to the quantitative relationship between the reimbursement ratio of the health insurance and the cost ratio of medical services.When the reimbursement rate is 0.95,the probability that the provider will choose rational behaviour to control health care expenditure is the highest.Conclusion Healthcare providers with higher reimbursement rates have a higher probability of choosing rational behaviour.At the same time,the medical insurance reimbursement ratio cannot be raised blindly.It is recommended that the level of health insurance benefits be reasonably adjusted,the construction of a differentiation of the reimbursement ratio of medical insurance should be improved,and the measures for the management of medical behaviors should be enhanced,so as to effectively meet the health needs of the elderly population while at the same time guaranteeing medical safety.

Objective To clarify the interaction among the interests and strategic choices of multiple subjects of medical insurance for the older people in China,and to provide a decision-making basis for the improvement of medical insurance policy for the older people.Methods An evolutionary game model was constructed based on evolutionary game theory and its steady state was simulated using Matlab R2021b software for the health insurer,the health care provider and the elderly.Results There is a conflict of interest between health insurance providers,healthcare providers and older people when all three parties consider maximising their own utility.In order to reach an evolutionary equilibrium,the strategic choice of the health insurance provider is to take"cost-cutting"behaviour to control the expenditure of the health insurance fund;the strategic choice of the older people is to increase the use of medical services to meet the demand for medical services;and the strategic choice of the medical service provider is related to the quantitative relationship between the reimbursement ratio of the health insurance and the cost ratio of medical services.When the reimbursement rate is 0.95,the probability that the provider will choose rational behaviour to control health care expenditure is the highest.Conclusion Healthcare providers with higher reimbursement rates have a higher probability of choosing rational behaviour.At the same time,the medical insurance reimbursement ratio cannot be raised blindly.It is recommended that the level of health insurance benefits be reasonably adjusted,the construction of a differentiation of the reimbursement ratio of medical insurance should be improved,and the measures for the management of medical behaviors should be enhanced,so as to effectively meet the health needs of the elderly population while at the same time guaranteeing medical safety.

Objective To clarify the interaction among the interests and strategic choices of multiple subjects of medical insurance for the older people in China,and to provide a decision-making basis for the improvement of medical insurance policy for the older people.Methods An evolutionary game model was constructed based on evolutionary game theory and its steady state was simulated using Matlab R2021b software for the health insurer,the health care provider and the elderly.Results There is a conflict of interest between health insurance providers,healthcare providers and older people when all three parties consider maximising their own utility.In order to reach an evolutionary equilibrium,the strategic choice of the health insurance provider is to take"cost-cutting"behaviour to control the expenditure of the health insurance fund;the strategic choice of the older people is to increase the use of medical services to meet the demand for medical services;and the strategic choice of the medical service provider is related to the quantitative relationship between the reimbursement ratio of the health insurance and the cost ratio of medical services.When the reimbursement rate is 0.95,the probability that the provider will choose rational behaviour to control health care expenditure is the highest.Conclusion Healthcare providers with higher reimbursement rates have a higher probability of choosing rational behaviour.At the same time,the medical insurance reimbursement ratio cannot be raised blindly.It is recommended that the level of health insurance benefits be reasonably adjusted,the construction of a differentiation of the reimbursement ratio of medical insurance should be improved,and the measures for the management of medical behaviors should be enhanced,so as to effectively meet the health needs of the elderly population while at the same time guaranteeing medical safety.

Objective To clarify the interaction among the interests and strategic choices of multiple subjects of medical insurance for the older people in China,and to provide a decision-making basis for the improvement of medical insurance policy for the older people.Methods An evolutionary game model was constructed based on evolutionary game theory and its steady state was simulated using Matlab R2021b software for the health insurer,the health care provider and the elderly.Results There is a conflict of interest between health insurance providers,healthcare providers and older people when all three parties consider maximising their own utility.In order to reach an evolutionary equilibrium,the strategic choice of the health insurance provider is to take"cost-cutting"behaviour to control the expenditure of the health insurance fund;the strategic choice of the older people is to increase the use of medical services to meet the demand for medical services;and the strategic choice of the medical service provider is related to the quantitative relationship between the reimbursement ratio of the health insurance and the cost ratio of medical services.When the reimbursement rate is 0.95,the probability that the provider will choose rational behaviour to control health care expenditure is the highest.Conclusion Healthcare providers with higher reimbursement rates have a higher probability of choosing rational behaviour.At the same time,the medical insurance reimbursement ratio cannot be raised blindly.It is recommended that the level of health insurance benefits be reasonably adjusted,the construction of a differentiation of the reimbursement ratio of medical insurance should be improved,and the measures for the management of medical behaviors should be enhanced,so as to effectively meet the health needs of the elderly population while at the same time guaranteeing medical safety.

Objective To clarify the interaction among the interests and strategic choices of multiple subjects of medical insurance for the older people in China,and to provide a decision-making basis for the improvement of medical insurance policy for the older people.Methods An evolutionary game model was constructed based on evolutionary game theory and its steady state was simulated using Matlab R2021b software for the health insurer,the health care provider and the elderly.Results There is a conflict of interest between health insurance providers,healthcare providers and older people when all three parties consider maximising their own utility.In order to reach an evolutionary equilibrium,the strategic choice of the health insurance provider is to take"cost-cutting"behaviour to control the expenditure of the health insurance fund;the strategic choice of the older people is to increase the use of medical services to meet the demand for medical services;and the strategic choice of the medical service provider is related to the quantitative relationship between the reimbursement ratio of the health insurance and the cost ratio of medical services.When the reimbursement rate is 0.95,the probability that the provider will choose rational behaviour to control health care expenditure is the highest.Conclusion Healthcare providers with higher reimbursement rates have a higher probability of choosing rational behaviour.At the same time,the medical insurance reimbursement ratio cannot be raised blindly.It is recommended that the level of health insurance benefits be reasonably adjusted,the construction of a differentiation of the reimbursement ratio of medical insurance should be improved,and the measures for the management of medical behaviors should be enhanced,so as to effectively meet the health needs of the elderly population while at the same time guaranteeing medical safety.

Objective To clarify the interaction among the interests and strategic choices of multiple subjects of medical insurance for the older people in China,and to provide a decision-making basis for the improvement of medical insurance policy for the older people.Methods An evolutionary game model was constructed based on evolutionary game theory and its steady state was simulated using Matlab R2021b software for the health insurer,the health care provider and the elderly.Results There is a conflict of interest between health insurance providers,healthcare providers and older people when all three parties consider maximising their own utility.In order to reach an evolutionary equilibrium,the strategic choice of the health insurance provider is to take"cost-cutting"behaviour to control the expenditure of the health insurance fund;the strategic choice of the older people is to increase the use of medical services to meet the demand for medical services;and the strategic choice of the medical service provider is related to the quantitative relationship between the reimbursement ratio of the health insurance and the cost ratio of medical services.When the reimbursement rate is 0.95,the probability that the provider will choose rational behaviour to control health care expenditure is the highest.Conclusion Healthcare providers with higher reimbursement rates have a higher probability of choosing rational behaviour.At the same time,the medical insurance reimbursement ratio cannot be raised blindly.It is recommended that the level of health insurance benefits be reasonably adjusted,the construction of a differentiation of the reimbursement ratio of medical insurance should be improved,and the measures for the management of medical behaviors should be enhanced,so as to effectively meet the health needs of the elderly population while at the same time guaranteeing medical safety.