More than 10 million Chinese high school students on Sunday started their three-day "battle to determine their fate," as the national college entrance exam is commonly known, amid concerns over flu and test cheating.

Although the number of candidates was down 3.8 percent from last year, the first decline in seven years, the college entrance examination, or "gaokao", is still the world's largest.

The fiercely competitive annual examination is widely regarded as the make-or-break test for university admission by the Chinese.

A battle for the future

Across China, parents prayed outside more than 8,000 test centers.

Although this year's admission rate is around 62 percent, 12 times higher than in 1977 when China resumed the college entrance exams after the 10-year-long Cultural Revolution, competition is still fierce.

"It was like thousands of people squeezed on to a narrow bridge where only a few could get to the other side 20 years ago when I sat the exam," said Zhang Xiuqing, a father waiting for his daughter outside a test center in downtown Beijing.

"Now it's the same because everyone wants to enter prestigious universities like Peking and Tsinghua," he said.

In a country where a college diploma can help secure a decent job, the annual college entrance exam is considered decisive in determining a student's future career opportunities.

However, at least 1 million graduates of the 5.6 million fresh out of university in 2008 failed to find employment as the job market shrank because of the global economic downturn.

They joined graduates from previous years who were still unemployed.

But still Zhang believed odds were still better for them than for those with no university qualifications.

"Whenever it is, success in the gaokao is a key to social mobility in China," he said.