The prevalence of CHE in Iran during 1997 and 2015 fluctuated from 1.97% (
13) to 24% (
21). Principally, the equity indexes such as CHE has a high inertia, and there is no possibility for immediate leaps in this index (
13). Therefore, to identify reasons for this inconsistency, the questionnaire and scope of studies, and year and sample size of surveys, should be checked by the results of subgroup meta-analysis and meta-regression. The results revealed that the highest percentage estimate of facing CHE is associated with author-made questionnaires and the lowest is related to the SCI questionnaire. The SCI questionnaire is a general tool which is used every year to estimate the income-expenditure of households and was not designed specifically for the health sector, whereas the other 2 are specifically designed for health care systems. Gotsadze et al. (2009), relying on evidence from Georgia, also stated that those questionnaires that have been particularly designed to study household expenditures for health services are more accurate (
31).
Another important finding of this study was summarizing CHE determinants. An overall examination of these variables shows that 11 of them, besides being ineffective, only increased the possibility of facing CHE, whereas 7 other variables had both increasing and decreasing roles.
In general, the variables, which have been ineffective or increased the possibility of facing CHE were as follow: having no health insurance, aging of the household head, unemployment of the household head, inhabitance of the household in the villages, having an elderly person in the household, having a disabled person in the household, having a household member who suffers from chronic or cardiac disease, and any use of health care services. On the other hand, 7 variables including lower income of the household, female household head, lack of education of household head, marital status of household head, the higher number of family members who have an income, more people in the household, and having a child in the household were among the factors that had both an increasing and a decreasing role in facing CHE in various studies.
Health insurance status is the only variable, whose effect on facing CHE was examined in all studies. Most of the studies indicated that having health insurance reduced CHE (
12,
14-
16,
20,
23,
24,
30). The purpose of acquiring health insurance is to gain financial security by accumulation and prepayment. Therefore, in nearly half of the studies having health insurance did not have a significant effect on reducing CHE (
12,
13,
18-
20,
27,
28). This, to some degree, shows the deficient function of insurance in Iran in which the cost coverage and service coverage are limited; moreover, as the payment franchise is high (
29), it has even reduced the protective effect of insurance.
Aging of the household head also increased the possibility of facing CHE (
15,
23). This variable can lead to households facing CHE by decreasing their ability to pay because of the weakened ability to work and lower income and by increasing heath expenditures due to their need for more care.
The unemployment of the household head increased the possibility of facing CHE (
15,
16). Employment is an index of one’s socioeconomic situation. The inability of a household head to make income can be directly related to a decrease in the ability of payment of the household.
The households living in a village have an increased possibility of facing CHE (
12-
16). This could result from lack of facilities in the village, the money and time spent to use city services, or the indirect expenditure of staying in the city to use those services. On the other hand, it could also be caused by the lower ability of villagers to pay. Nevertheless, expensive private facilities in cities can also increase CHE (12).
Having an elderly person in the household increases the possibility of facing CHE (
13,
16,
20,
23,
30). The elderly may need more expensive health care services. Also, in most of the reviewed studies, having a disabled person (
14) or a person with cardiac or chronic diseases in the household increased the household’s possibility of facing CHE (
12,
14,
23,
30). It seems that the presence of these people in the household, aside from imposing heath expenditures, resulted in other household members wasting their time and losing their opportunity to work and produce income.
In most of the studies, any use of health care services, e.g., hospitalization (
12,
18,
20,
24,
28,
30), outpatient services (
12,
14,
18), times of utilization of services (
12,
27), dentistry services (
12,
24,
25), and the cost of medicines (
18,
20,
25) increased the possibility of facing CHE. It seems that the health care system in Iran has created less financial protection for those who are in need of such services. This situation is worse when one considers that the CHE index does not consider those households that have unmet needs.
In this systematic review, some factors increased the possibility of facing CHE, while in other studies they actually decreased it. Income seems to be one of the most effective factors in the possibility of facing CHE. In general, an examination of the effect of a household’s economic situation on the possibility of facing CHE revealed that the possibility of facing CHE is higher in low-income households (
12,
14,
18,
24,
30). Clearly, since CHE is calculated based on the ability to pay, it is highly sensitive to the financial situation of a household. Only 2 studies revealed that the possibility of facing CHE was greater in high-income households (
16,
23). This could have resulted from the fact that poor families usually refrain from using health care services, or use cheaper services in the public sector, or it could be a result of protective policies that mostly cover poor households (
32).
The variable of female household head increased the possibility of facing CHE in 2 studies (23, 30) and decreased it in another (
18). Therefore, it seems more appropriate to consider this variable as interacting with other variables such as education or place of residence (city or village) (
33).
Low education level of the household head increased the possibility of facing CHE in some studies (
13,
15,
23,
28). The reason for this was that educated people take more appropriate care of their health. They also use health and preventive care services more effectively. Moreover, it can be stated that households with economically-active heads (with a lower possibility of facing CHE) are mainly educated (
32). However, the results of 1 study revealed that households with educated heads are more in danger of facing CHE (27). This can be a result of more awareness, more visits to health and medical centers, and more money spent on health care services.
In most of the studies, the higher number of household members increased the possibility of facing CHE (
14,
16,
20,
25,
27), yet the results of some studies showed a decrease in the possibility of facing CHE (
15,
18,
23). Therefore, the variable of household size should not be considered alone, when explaining the possibility of facing CHE; the variables such as average age of household members and the level of use of health care services need to be considered along with household size. Households with 1 and 2 members including single individuals or couples with an average age of 46 years or more should also be considered (
34). On the other hand, people in more crowded households take care of each other, and this leads to a reduction in use of health care services by household members (
35).
According to the results of several studies, the presence of a child (or children) increases the possibility of facing CHE (
13,
16,
23). Children are more vulnerable to diseases and injuries than other age groups. Conversely, some studies revealed that the presence of children in a household had a protective role in facing CHE (
20,
25). In a household with a preschool child, the parents are normally young, possibly healthier, and thus less likely to face CHE.
Various plans such as the health sector evolution plan (HSEP) (
36) since 2014 were implemented in the Iranian health care system to reduce OOP payments; thus, one of the interventions of HSEP was reducing OOP payments just for inpatient services, and this plan does not cover outpatient services, which according to the results of this research, can increase the probability of facing CHE. It seems necessary to investigate the effect of this plan on household facing CHE in Iran. In this study, only 1 survey had used cross- sectional data after HSEP plan, thus, we could not use subgroup meta-analysis to investigate the effect of this plan.
5.1. Conclusion
Policymakers should consider that researchers may use different instruments to calculate CHE and have different results. Decreasing CHE level to less than 1%, the objective of 2 Iran’s five-year development plans (2007 - 2015), was not met in Iran. This percentage may need to be reconsidered according to the pooled estimate of CHE. The determinant factors of facing CHE in Iranian households revealed that some socioeconomic variables increase the possibility of facing CHE by lowering one’s capacity to pay and increasing the need so that interventions to influence these variables are not solely in the domain of the health sector, and some intersectoral collaboration must be taken to improve the welfare of the vulnerable groups.
It is suggested that households that are simultaneously affected by several factors of CHE be given priority. It is also recommended that in future studies the interactive effect of these variables in facing CHE be investigated to provide detailed information to administrators.