Teenagers who have committed knife possession offences achieve poorer results at GCSE or equivalent level compared with the entire pupil population but also with other types of offenders, official analysis has revealed.

Just under 50% of young offenders who have committed knife possession offences attained five or more GCSEs with an A* to G grade, compared with 90% of all pupils, just over 60% of all offenders and 55% of theft offenders, according to a report from the Ministry of Justice and Department for Education.

The study also found that more than 40% of knife possession offenders were eligible for free school meals, compared with 15% for all pupils, just under 35% for all offenders and just over 35% for theft offenders.

The study, based on a group of pupils in England who reached the end of key stage 4 in 2012-13, aims to provide greater insight into the backgrounds of offenders. But it made clear the analysis did not imply a link between educational outcomes and offending.

The study also revealed that cases of persistent absence and temporary or permanent exclusions from school among those with knife possession offences was greater than among all comparison groups.

Eighty-three percent of knife possession offenders were persistently absent from school in at least one of the five academic years from 2008-09 to 2012-13, compared with 82% of theft offenders and 78% of all offenders.

A separate batch of Ministry of Justice figures revealed that in the year ending in March the criminal justice system dealt with 21,045 knife and offensive weapon offences – the highest number since the year ending March 2012.

There has been a surge in knife and gun crime this year, particularly in London. The former home secretary Amber Rudd launched a serious violence strategy in April amid controversy over the potential link between dwindling police numbers and the rise in crime. The strategy is to be backed by £40m of Home Office funding and a new offensive weapons bill to ban the sale of corrosive liquids to under-18s and introduce tougher restrictions on buying knives online. It will focus heavily on the links between illegal drug markets, particularly for crack cocaine, and violent crime.