A record 16 students have achieved the perfect score in this year's Diploma of Secondary Education (DSE) exams.

A day ahead of the release of exam results, the Hong Kong Examinations and Assessment Authority (HKEAA) said on Tuesday that on top of getting 5** across six subjects and achieved "attained" in the citizenship and social development (CS) subject, one of them achieved the top score in two additional subjects.

The 16 were among around 18,200, or 42.5 percent of the 42,800 secondary school candidates who reached the minimum university admission requirement of "332A22".

This means that they obtained at least levels 3 in Chinese and English languages, a level 2 or above in the mathematics compulsory part and levels 2 or above in two electives.

CS has replaced liberal studies since last year.

"In terms of the number of top scorers, I think it's the record-breaking year, the highest over the history of the DSE examination," Wei Xiangdong, secretary general of the HKEAA, told a press briefing.

"However, I have to remind you that because of the change of subjects from liberal studies to CS, so maybe it's not directly comparable before 2024 and after 2024."

The top scorers – 11 boys and five girls – came from 14 schools across Hong Kong.

Choy Siu-kwan, HKEAA's head of assessment development, said the record-breaking figure of top achievers might be due to the replacement with CS, which had enabled students to take on additional subjects.

Separately, the authority said two elderly candidates, aged 66 and 71, took the exams, while the youngest was only 10 years old.

It also said that six candidates were found to have cheated. All but one of them have had all their results disqualified.