The first Scottish Survey of Achievement for pupils aged five to 14, published in full today, shows most are at or above the literacy and numeracy levels for their age.
The results give a snapshot of pupils' performance in reading and numeracy at both national and local authority levels. Schools are not identified.
But it is only half the picture, as the tests were carried out last year in only 16 education authorities (see table); figures from the other 16 will be available next year.
The data, based on testing more than 28,000 pupils in P3, P5, P7 and S2 in 1,300 schools, confirms trends evident from the 5-14 tests and the Assessment of Achievement Programme, both of which the SSA supersedes.
Once again, the picture is one of steady improvement, especially at the primary stages, and of a dip in performance in S2. But significant numbers are doing better than expected and attainment in some authorities is also bucking the trend.
Explanations for the variations in performance between levels and across the country are not readily apparent. As one official put it: "These results do not provide any answers, but they do provide schools with many questions to compare their own performance with the national and local authority picture."
The figures confirm that pupils hit their targets progressively less well as they become older - from 75 per cent at level A in P3 to 49 per cent at level E in S2 in reading, and from 91 per cent at level A in P3 to 45 per cent at level E in S2 in numeracy.
If, however, the number who are described as having made a "good start"
(answering more than half the test questions correctly) are added, the literacy results in P3 are 88 per cent and 71 per cent in S2, while the numeracy figures rise to 97 per cent in P3 and 68 per cent in S2 - although the progressive dip in performance through the stages is once again underlined.
Peter Peacock, the Education Minister, took some comfort from the fact that many pupils were performing at a level above what is expected. In reading, for example, 71 per cent of P3 pupils are "well-established" or better at levels B and C, while 30 per cent of P7 pupils are already at level E, two years early.
Individual education authorities follow suit: 43 per cent of East Renfrewshire's P7 pupils are at level E in numeracy, as are 47 per cent in literacy, for example.
The survey also notes the variations in performance between authorities at different stages. In reading, the range for P3 pupils turning in well-established or better results at level B in reading stretches from 40 per cent in North Ayrshire to 61 per cent in East Dunbartonshire.
While the links between attainment and deprivation are largely confirmed, there are exceptions. "In the three authorities with the highest levels of income deprivation, Inverclyde clearly stands out for its generally positive picture of attainment," the report states.
It also notes that, in other authorities with slightly higher levels of deprivation than the norm, reading results are better than expected - for P5 in Edinburgh, for example. Good performances were also seen from P3 pupils in Highland and P7 classes in Aberdeen.
Deprivation also plays its part where pupils get 50 per cent or less of their answers right - the lowest figures are in East Renfrewshire and East Dunbartonshire, while the highest are in North Lanarkshire in P3 and in North Ayrshire. But South Ayrshire in P3, Renfrewshire at all primary stages and Highland in S2 had fewer pupils in this group than would have been expected.
Generally, however, the report notes that "the results of the survey for some of the local authorities show a particularly encouraging picture in P3 and P5, suggesting that their recent approaches to raising attainment in the early years might be having a particularly positive impact on attainment in reading, and particularly for lower achieving pupils - 'closing the gap' at the earlier stages."
In numeracy, a similar picture emerges. Again, Inverclyde is singled out for doing well: the performance of its P5 pupils at level C is better than that of Perth and Kinross, one of the least deprived areas.
Pupils in Highland, South Ayrshire, South Lanarkshire and Renfrewshire did better than expected in the numeracy tests, while those in Edinburgh and Aberdeen did less well.
The executive is cautious about comparing these results with previous surveys, since the SSA is a new testing system and the results will be different. In reading, however, it has been possible to compare results for P7 and S2 with those from the Assessment of Achievement Programme five years ago. It shows that "attainment has improved since 2001 at both stages and at all levels, with the exception of level F at S2".
Comparing the SSA numeracy results with the AAP maths survey in 2000, the major change is the big improvement at level D in both P7 and S2.
Overall, the executive believes the results are a robust and accurate picture of pupils' performance at the key 5-14 stages, since the schools were selected to be representative of different types of school, the pupils were randomly selected according to birth date and the test questions were also allocated at random to each pupil.
The next SSA surveys, over the next two years, will cover the social subjects, science and maths.
The full SSA report and survey results can be found on The TESS website, www.tes.co.ukscotland