The ground-breaking Edinburgh University studies on youth transitions and crime say truancy is more prevalent among teenage girls than boys in Scotland.
They found that just one in five truants at primary school was a girl but the corresponding figure in the third year of secondary school was three in five.
The truancy study suggests that "there is something about being a female or a risk factor to which girls are more prone, which is linked to truancy and which is not currently being measured. This would repay further investigation."
The report adds: "To be effective, policy requires greater awareness of sex differences in patterns of truancy, and should focus in particular on the needs and problems presented by teenage girls." One insight the study offers is that truants have particular personalities: they are impulsive and prone to risk-taking as well as having low self-esteem.
Exclusions appear to be a different story. Boys in this study were more likely to be excluded from school than girls, making up almost three-quarters of the third-year total. The most likely to be "consistently singled out" for exclusion are young males, those from deprived backgrounds and those not living with both parents.
The studies, hailed as of "major international significance" by the Economic and Social Research Council, which helped fund the work, tracked 4,300 young people who transferred to Edinburgh secondary schools in 1998.
Four reports issued this week examined truancy, parenting, gender and victimisation among young people and looked at the links to delinquent and criminal behaviour. The truancy report pointed to the link between negative experience of school and absenteeism, which suggested to the researchers that policy must concentrate on promoting discipline in schools and fostering "pro-school" attitudes among young people and their parents.
Many of the other findings will be unsurprising, such as the connections between truancy and deprivation, drugs misuse and offending - half of all 15-year-old truants reported using drugs in the previous 12 months.
The report also notes, however, that truancy is triggered by high volumes of bad behaviour at school and high levels of punishment meted out by the school. The "weakest link" in sparking truanting behaviour is poor relationships with teachers.
Parenting, however, is a major factor: truants tend to have less home supervision than others and to be in greater conflict with their parents.