The number of Otago secondary schools failing to meet the national average pass rate in all levels of NCEA continues to rise, recently released statistics from the New Zealand Qualifications Authority show.
This contrasts with the number of secondary school pupils gaining NCEA qualifications nationwide, which has increased at all three levels for the ninth consecutive year.
During the past five years (2009-2013), the number of Otago schools failing to match, or better, the nation's levels 1, 2 and 3 roll-based pass rates has grown from two to five in level 1, seven to nine in level 2, and nine to 12 in level 3.
However, Otago Secondary Principals' Association chairman Mason Stretch said drawing conclusions about a greater number of schools ''not at national figures'' was problematic.
He questioned how many were within 1% or 2% of the national figure.
''It could be as little as a 0.5% change for two or three schools that takes them into the red, when, in fact, there is little significant change in results.
''Counting up those schools below does not take into account the positive changes individual schools are making to raise achievement.
''I know of several schools on the list that have made improvements but they are still below for one or two NCEA levels.
''That progress is significant and important, but not shown in the results.''
Mr Stretch said all schools were looking critically at their NCEA results and aiming to provide the best opportunities for pupils.
''My quick look at the figures suggests that rural schools are doing well.
''There is clearly variation between schools but there are many factors that are not considered here, such as the socio-economic wellbeing of the school's community and school decile.''
He said it was also important to note how well pupils in the Otago region achieved nationally.
He believed it was one of the-best performing regions nationally for NCEA achievement.
''On the whole, students in this region benefit from well run schools, with committed boards of trustees and staff, and supportive communities.''
An NZQA spokeswoman said the statistics assisted schools and teachers in their planning and any comparisons made between schools should be treated with caution.
Schools designed their courses and qualifications for pupils differently and the public should be aware of factors such as decile, roll numbers and courses offered, which would influence statistics, she said.