Confirming results from other parts of the country, the 19 schools involved in early intervention strategies helped pupils make more advances than the other 40 that did not take part.
John Stodter, the city's director of education, said: "The good news is that although the actual early intervention scheme had only been running for a few months, it had made an impact."
Aberdeen has used baseline testing at the beginning and end of primary 1 in reading, numeracy and rhyme and teacher reports to assess progress in all 60 schools. The city has opted for Durham University's PIPS system (Performance Indicators in Primary Schools) to assess pupils. Tests are short and externally marked.
Dr Linda Croxford of Edinburgh University's Centre for Educational Sociology has been employed as an independent researcher. Her report, presented this week to the city's education committee, shows that in reading:
* Pupils who had high baseline reading attainment when they entered school made relatively more progress than children who started with low reading skills.
* Children who came from relatively poor home backgrounds made less progress on average than other pupils.
* Girls made more progress than boys.
In mathematics, however:
* Pupils with low baseline scores made relatively greater progress than pupils with high baseline attainment.
* Pupils from relatively poor backgrounds made as much progress as other pupils.
* Girls made less progress than boys.
Pupils involved in the first phase of the early intervention project made more progress in reading and there is "some evidence of catching up" by pupils whose initial attainment was low.
The results also suggest differences between schools in the rates of progress in primary 1. In some schools progress was significantly greater than average after taking all other factors into account. The relative progress of pupils with initially low or high attainment also differed among schools.
Some differences are likely to be attributable to the relative effectiveness of teaching and learning approaches, although the city is treating the data cautiously.
Mr Stodter said: "The report by Dr Croxford is very significant. It represents the beginning of a pupil-level information system which will enable us to evaluate the relative impact of different intervention strategies in different schools and on different groups of pupils.
"The real pay-off in providing performance information of this kind is in the insights gained into individual pupil progress, the discussion which is generated and the actions which follow."
Mr Stodter believes the findings beg a number of questions about improving attainment. Schools, as part of their self-evaluation processes, needed to investigate how to help disadvantaged readers catch up, how to push younger pupils and how to prevent gender differences in primary 1.
Among other findings, Dr Croxford concluded that younger pupils, children living in areas of deprivation and children with English as a second language made as much progress as other pupils but there was no evidence of them catching up from their initial lower attainment.
The age at which pupils enter primary 1 was also important. Pupils joining P1 in August 1997 ranged from 41 months to 79 months. Normally the average is between 54 and 65 months. But 11 per cent were younger than 54 months and 20.5 per cent older than 65 months.
A difference of one month in a child's age makes a difference on average of 0.3 per cent points on maths and reading scores, Dr Croxford notes.