Unsurprisingly, water pollution was negatively associated with health outcomes, and the common pollutants in industrial wastewater had differential impacts on health outcomes.

The effects were stronger for low-income respondents. Water environment treatment led to improved health outcomes among Chinese people.

Reduced water pollution mediated the associations between water environment treatment and health outcomes. The results of this study offer compelling evidence to support treatment of water pollution in China.

Since the 1970s, China has experienced dramatic environmental degradation, including water pollution, as a by-product of rapid economic development and industrialization (Ministry of Environmental Protection, 2015). Pollutant discharge causes widespread organic pollution, toxic pollution, and eutrophication, along with severe ecological destruction (Miao et al., 2012). For example, the latest review showed that the Tonghui River and Guanting Reservoir of Beijing, Minjiang River Estuary and Wuchuan River in China had comparatively higher ranges and mean values of dichlorodiphenyltrichloroethanes (DDTs) and hexachlorocyclohexanes (HCHs) in water (Ahmed et al., 2015). Concurrent with the water pollution, the country has also experienced an increase in health risks (Lu et al., 2015). Approximately 190 million people fall ill and 60,000 people die from a range of other diseases and injuries associated with water pollution each year (Tao and Xin, 2014).

The health impacts of water pollution are of increasing concern for Chinese citizens and policymakers, and the unaddressed health consequences at regional and global levels pose major policy challenges (Lu et al., 2008 and Miao et al., 2015). Over 70 percent of Chinese people feel threatened by water pollution (China Youth Daily, 2013). The country has stepped up its efforts to tackle the problem (Zhang et al., 2012 and Zhang et al., 2013). Generally, increasing environmental awareness coupled with more stringent regulation standards has triggered various industries to challenge themselves in seeking appropriate wastewater treatment technologies (Teh et al., 2016a).

As is well known, there are substantial differences in smoking behavior in China with Chinese men smoking at vastly higher rates than Chinese women. In the CHARLS age group Chinese men smoke at a ten times higher rate than women (73% compared to about 8% for women). The age pattern of smoking behavior in the CHARLS cohort documents the secular trend towards increased levels of smoking in China by younger cohorts particularly Chinese men (Yang et al., 1999). While a comparison of ever and current smoking behavior does indicate that there was some quitting behavior among smokers it is nowhere near what took place in many developed countries such as the United States (Preston et al., 2010). The negative consequences of this widespread smoking behavior lie in the future and will undoubtedly make healthy aging the far more difficult particularly for Chinese men.

A similar concern comes from the overweight data in Table 2 as we see high levels of being overweight now for both men and women alike with particularly high rates among the youngest age group where 38% of the Chinese women and 28% of the Chinese men are over-weight.

Up to 2003 the majority of Chinese population did not have access to health insurance and only the urban employees were covered. Since 2003 New Cooperative Medical Scheme (NCMS) was introduced to cover rural residents and since 2008 Urban Resident Medical Insurance was implemented to insure non-workers, i.e., children and the elderly. The government has been subsidizing both of the new medical insurance schemes by paying 3/4 of the insurance premiums. The NCMS, the largest insurance scheme in China, started with extremely low premiums, at 30–40 yuan in 2003, and reimbursed very little of the medical costs. Attracted by the large government subsidy, the insurance expanded rapidly and covered most of the rural population by 2008. In 2011, around 93% of Chinese 45 and older have health insurance (Table 2). The premium and reimbursement rates steadily increased year by year. In 2014, premium has reached nearly 400 yuan. Correspondingly, reimbursement rate has increased significantly.

The NCMS insurance pools are operated at the county level. They discourage medical treatment at higher-level hospitals. Take inpatient care, for example, a typical policy is as follows: copayment/reimbursement at local township hospital is 200 yuan/85% while at tertiary hospital is 700 yuan/55% (city hospital) or 1000 yuan/50% (provincial hospital). Living out of one’s county of registration is universally penalized. Co-payment is higher and reimbursement is 10% lower than in one’s own county. In addition, patients need the referral from own county hospital in order to get treatment elsewhere. This is costly for a patient living away from home.

Living arrangements of the Chinese elderly
Family has been the traditional source of elderly support in China for economic assistance and for elderly care. This arrangement is facing unprecedented challenges due to a drastic decline in the numbers of and out migration of children. To illustrate the fertility decline, Chinese women older than 74 have an average of 4.6 children ever born, those between 60 and 75 have 3.4 children while those between 45 and 59 only have 2.2 children (second to last column, Table 2). The number of living children is slightly lower, but the pattern remains (last column, Table 2).

At the same time, adult children are increasingly moving away from their parents. This out-migration is fueled by large and persistent income gaps between urban and rural areas and between inland and coastal regions. Younger people are more likely to migrate due to lower psychic cost associated with changing living environment and higher future returns from investing in migration (Sjaastad, 1962). The pattern is observed in China as well (Zhao, 1999).

Another driving force behind migration of young adults in China is the significant increase in education in younger generations. Education gives rise to information advantages that reduces search costs. Additionally, most higher education institutions in China are located in developed urban areas so that younger generations often must move to attend school.

Criteria for use of Composite Endpoints for Competing Risks – A Systematic Survey of the Literature with Recommendations

Background

Composite end points are frequently used in reports of clinical trials. One rationale for the use of composite endpoints is to account for competing risks. In the presence of competing risks, the event rate of a specific event depends on the rates of other competing events. One proposed solution is to include all important competing events in one composite endpoint. Clinical trialists require guidance regarding when this approach is appropriate.

Objectives

To identify publications describing criteria for use of composite endpoints for competing risk and to offer guidance regarding when a composite endpoint is appropriate on the basis of competing risks.

Data Sources

We searched MEDLINE, CINAHL, EMBASE, The Cochrane’s Central & Systematic Review databases including the Health Technology Assessment database and the Cochrane’s Methodology register from inception to April 2015, and candidate textbooks, to identify all articles providing guidance on this issue.

Study Selection and Data Extraction

Eligible publications explicitly addressed the issue of a composite outcome to address competing risks. Two reviewers independently screened the titles and abstracts for full text review; independently reviewed full text publications; and abstracted specific criteria authors offered for use of composite endpoints to address competing risks.

Results

Of 63645 titles and abstracts, 166 proved potentially relevant of which 43 publications were included in the final review. Most publications note competing risks as a reason for using composite endpoints without further elaboration. None of the articles or textbook chapters provide specific criteria for use of composite endpoints for competing risk. Some advocate using composite endpoints to avoid bias due to competing risks and others suggest that composite endpoints seldom or never be used for this purpose. We recommend using composite endpoints for competing risks only if the competing risk is plausible and if it occurs with sufficiently high frequency to influence the interpretation of the effect of intervention on the endpoint of interest. These criteria will seldom be met. Review of heart failure trials published in the New England Journal of Medicine revealed that many of them use the composite endpoint of death or hospitalization; none of the trials, however, satisfied our criteria.

Conclusion

The existing literature fails to provide clear guidance regarding use of composite endpoint for competing risks. We recommend using composite endpoints for competing risks only if the competing risk is plausible and if it occurs sufficiently often.

This is a serious topic