'Are you sure?': Academics question claim mainland cities ahead of Hong Kong in English

Academics and politicians took issue with a global study of English-language skills that ranked Hong Kong adults marginally lower than residents of major mainland cities including Shanghai, Beijing and Tianjin.

The annual study, known as the English Proficiency Index, is compiled by the Swedish-owned global language instruction company EF Education First. This year's index is based on test results gathered last year from about 750,000 people across 63 countries and regions.

A local representative of US employers said the drop among Hongkongers could be due to public schools switching from English to Chinese as their language of instruction.

But critics of the study cautioned that the research samples in some of the regions might have skewed the results.

Professor Simon Haines, chairman of Chinese University's English department, asked people to "be cautious of rankings".

International publications had raised questions over the methodology used in such test-based rankings because the sampling base varied across different regions, he noted.