"Ambitious parents will look at every possible way to get their kids into those schools. Unethical consultants prey upon wealthy parents, assuring them they can get their kids into their dream schools," she said.

Rahul Choudaha, executive vice-president of research at Studyportals, a US company that recruits international students online, said the high demand and aspiration for admission to elite universities have opened the door for unscrupulous consultants to sell "shortcuts" to families and students.

"This is where some consultants are reverse-engineering the university admission process and selling it as a service to families," said Choudaha, an expert on international student trends.

He said many of these leading universities are very strong in terms of their appeal to families around the world, so they are likely to overcome any short-term reputational damage and continue to attract interest from students and families.

"But universities must move forward to enhance the transparency and availability of information about admissions processes so that intermediary consultants cannot take advantage of the information gap, Choudaha said.

Venturini said: "There are only 11 universities out of 4,298 degree-granting post-secondary institutions in the US that have been involved in the college admissions scandal. Don't get caught up in all the hysteria."

But Shen, the mother of the high-school student in Palo Alto, has had second thoughts about elite colleges.

"I would have spared nothing to get my daughter into Stanford before I came to the US," said Shen, who has lived in the city where Stanford University is located, for four years.

"I think the efforts (of the Zhaos) are not worth it. I've seen many Stanford professors' children attend a local community college, and they are happy with it. Now, I want my daughter to choose the college she likes."