In contrast to the HI system established within the United States, China’s social HI system is provided by and paid for by the state [27,28,29]. China’s multi-level social HI system includes urban employee basic medical insurance (UEBMI) for the urban employed population and retirees, urban resident basic medical insurance (URBMI) for the urban unemployed population, and the new cooperative medical scheme (NCMS) for the rural population . The UEBMI is considered most generous and, along with government medical insurance for government employees and private medical insurance either purchased by work unit or individuals, cover about 80% of the cost of medical care. URBMI is considered a moderate-coverage HI and, along with urban and rural resident medical insurance developed in advanced communities, cover 50–80% of the cost of medical care. NCMS is considered low-coverage HI and, along with the new rural cooperative medical insurance (he-zuo-yi-liao), cover less than 50% of the cost of medical care.
Our study analyzed data from CHARLS 2018 survey and found that the majority of Chinese adults had some HI coverage. In 2018, 3.15% of Chinese adults were uninsured, compared to about 13% of US adults who were uninsured in the same year .
One important finding of our study was that HI coverage was significantly and positively associated with access to care. Specifically, we observed that Chinese adults with HI were more likely to have physical examinations, office visits, and inpatient care than those with no insurance- a finding which was similar to studies of the US [16, 17, 20, 30] and India , even though these latter studies examined different indicators related to access to care [16, 30, 31]. Researchers in the US  showed that CHC patients with insurance coverage were more likely to have access to necessary medical care (OR = 2.12), see a recommended specialist (OR = 2.73), see a mental health professional if advised to do so (OR = 1.74), receive recommended follow-up care after an abnormal pap smear (OR = 3.44), and obtain necessary prescription medications (OR = 2.10) (particularly high cholesterol medications (OR = 2.25), compared to similar CHC patients without insurance. Among privately- and publicly-insured cancer survivors, those with coverage disruptions were less likely to report all preventative service use (16.9% vs. 36.2%; 14.6% vs. 25.3%, respectively) and more likely to report problems with care affordability (55.0% vs. 17.7%; 71.1% vs. 38.4%, respectively) and cost-related medication nonadherence (39.4% vs. 10.1%; 36.5% vs. 16.3%, respectively), compared with those continuously insured . The results from another US study suggested that the high uninsured rate among Mexican migrant workers in the US contributed to inadequate access to care in the country overall . A further US study noted that the Medicaid expansion resulted in substantial increases in insurance coverage and was associated with significant reductions in delaying care . In the study from India , researchers found that individuals enrolled in HI specified for the poor had 1.21 times higher odds of hospitalization incidences when compared to poor individuals without HI coverage. Researchers analyzed the piloting of a preferred provider system (PPS) for rural members of Vimo SEWA, a fixed-indemnity, community-based HI (CBHI) scheme in India  and showed that it successfully directed members to inpatient facilities with acceptable level of technical quality . A study from P.R. China showed that compared with the insured, the respondents without medical insurance had 73% less probability of using outpatient services in the past month, 49% less probability of hospitalization in the past year,67% less probability of receiving routine physical examination in the past 2 years, and 84% less probability of receiving other treatment in the past month .
In this study, we also found that Chinese adults with HI were more likely to be satisfied with quality of care than those with no insurance, which was different from previous study findings from Ghana . The definition of satisfaction may have varied, affecting the results of our study. For example, satisfaction was measured from the following domains in a Nigerian study : accessibility, patient waiting time, patient–provider communication, patient–provider relationship, hospital bureaucracy, and hospital environment. Patients were then categorized in the binary, with those who scored 50% and above in the assessed domain were considered satisfied, while those who scored less than 50% were dissatisfied . In our study, Chinese interviewees were simply asked if they were satisfied with “the quality, cost, and convenience of local medical services.” However, the result of our study was consistent with another China study which showed that community elderly chronic patients with medical insurance were more satisfied with service quality and medical expenses than patients without medical insurance (76.28% > 61.11%, 81.01% > 59.30%, respectively) .
Perhaps the most important finding of our study was that there was a significant gradient association between extent of insurance coverage and access to care. We found that adults with high-coverage HI had much higher odds of having regular checkup when compared to adults with moderate-coverage or low-coverage (ORs with 95% CI: 5.464 [4.370–6.831] > 2.462 [1.983–3.057] > 1.819 [1.485–2.229]). Likewise, when compared to adults with moderate-coverage or low-coverage, those with high-coverage HI had higher odds of having physician office visits (ORs with 95% CI: 1.496 [1.125–1.990], 1.398 [1.056–1.852],1.344 [1.040–1.752]) and inpatient care (ORs with 95% CI: 2.572 [1.862–3.552], 2.065 [1.498–2.846], 2.068 [1.520–2.812]). This result implies that while HI is important in general, adequate coverage is also essential to improve access to care particularly preventive care (our checkup measure), primary care (our physician office visit measure), and tertiary care (our inpatient care measure). Alternatively, this finding could also indicate the presence of a sizable number of Chinese individuals who remain under-insured and thereby experience barriers to and inaccessibility of healthcare.
There were a number of limitations with this study. The cross-sectional nature of the data makes it impossible to assess causality. Therefore, our findings demonstrated associations rather than causal relationships. We were also limited by the number of measures within CHARLS which restricted the analyses performed. Noticeably absent were quality of care and cost of care measures, both critical in assessing the impact of HI. Finally, the impact of COVID was not assessed by the dataset. Under COVID type of insurance coverage and payment could greatly affect access to healthcare. Future research should look at longitudinal effect of extent of insurance coverage on access, quality, and cost of healthcare and under circumstances like COVID.
Insurance status in China is also tied to patient satisfaction, the standard by which healthcare quality is assessed. Patients with adequate insurance and fewer incidences of catastrophic hospital costs are more satisfied. Higher satisfaction rates have also been observed in patients with UEBMI insurance status [32, 33]. The fulfillment of patients’ expectations of insurance benefits and coverage was the major predictor of patient satisfaction. However, this expectation of insurance benefits varies from rural to urban populations. In a 2016 study of 1200 respondents, rural patients were noted to have lower expectations for the insurance plan and as a result, significantly higher levels of satisfaction with care received when compared to their urban counterparts. Beyond expectations for insurance coverage, urban patients’ levels of satisfaction was also tied to convenience of hospital location, more choices of treatments, and more thorough physical check-ups [32,33,34].
In sum, our study is one of few recent studies that used a country’s representative sample survey to study the association between extend of HI coverage and access to needed healthcare (preventive, primary, and tertiary). We showed that not only HI mattered in enhancing access to care but that there was a significant gradient association between extent of HI coverage and access to care with higher coverage relating to better access.