"One of the results was that adverse effects were more common for girls than for boys.

"Another intriguing result was that for boys, adverse effects were correlated with consent. But for girls, consent did not have an effect, which lends minor support to the idea of later perceived betrayal being the issue for girls. It was a small effect, as I recall."

Adverse effects were very small for both boys and girls, and though adverse effects were greater for girls the difference was still very small.

While we don't know the exact cause for these effects, it is worth keeping in mind that there is some degree of cultural approval for boys who seek out sex and some degree of cultural condemnation for girls who enjoy sex. Whereas cultural attitudes influence individuals, it is not at all surprising that there are adverse effects - the surprise is that given these cultural influences the adverse effects are so small.