In research published January 10 in Science, Professors Lisa Cameron and Lata Gangadharan from Monash University, Professor Xin Meng from the Australian National University (ANU) and Associate Professor Nisvan Erkal from the University of Melbourne examined cohorts of children born just before and after the OCP was introduced. They assessed social and competitive behavioural attributes such as trust and risk-taking.

The researchers conducted a series of economic games on more than 400 subjects. The imposition of the OCP allowed them to identify individuals who grew up as an only child because of the policy and who would have grown up with siblings in the absence of the OCP.

Comparing this group with those who were born before the OCP, they isolated the causal impact of growing up as single children. Results indicated that individuals who grew up as single children as a result of China's OCP were significantly less trusting, less trustworthy, more risk-averse, less competitive, more pessimistic, and less conscientious individuals.

Professor Cameron, of the Monash Centre for Development Economics, said effects were observed even if single children had significant contact with social peers.

"We found that greater exposure to other children in childhood -- for example, frequent interactions with cousins and/or attending childcare -- was not a substitute for having siblings. There is some evidence that parents can influence their children's behavior by encouraging pro-social values," Professor Cameron said.

The researchers considered a number of possible other factors such as participants' age and whether they might have become more capitalistic over time. They found that being born before or after the introduction of the OCP best explained the results.

The research may also have economic implications.

"Our data show that people born under the One Child Policy were less likely to be in more risky occupations like self-employment. Thus there may be implications for China in terms of a decline in entrepreneurial ability," Professor Cameron said.

A radical tool of population control, the OCP was introduced in 1979 and strictly enforced in urban centres using economic incentives. In 2011 an official Chinese outlet cited the numbers of births prevented at 400 million.

Reports indicate that the Chinese government is currently considering whether to relax the OCP and these findings are relevant to those deliberations.

Note: If no author is given, the source is cited instead.

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