I am worried by the trend of ever-improving O-level results ("Best O-level results since 1978"; Jan 12).

I first observed this trend when my brother, who was in the first batch of O-level students after the Integrated Programme was introduced, told me how students at his school apparently scored the best O-level results in years.

Subsequent stories from friends at other schools reinforced the idea that grades were generally inflated after the introduction of the Integrated Programme.

The recent news that this year's results were the best in so many years, even after most of the cream of the crop had been siphoned away into the Integrated Programme, strikes me as unbelievable.

Are we suffering from grade inflation? Grade inflation is a phenomenon where an ever-larger proportion of students score better results.

The Primary School Leaving Examination, by nature of its T-score system, is immune to inflation because the T-score reflects a pupil's ability relative to his peers.

However, the O- and A-level grades are given arbitrarily, with no known quotas, so "record-best" scores may simply reflect generosity on the part of the exam board rather than the genuine ability of students.

In severe cases, as happened in Britain, so many students received As that grades lost the ability to distinguish the more able students from the weaker ones, complicating university entry and making a farce of the exams.

In short, while we must continue to improve the education system, we cannot rely on grade distribution as an indicator, or we will simply be deceiving ourselves.

Sum Siew Kee