In another mark of the increasingly digital life of teenagers, more than 25 percent of those who dated said their love interests threatened or harassed them online or using texts, according to a new study that is touted as the most comprehensive look at the phenomenon.

Teenagers reported that their social networking accounts were hacked without permission, that they were texted about unwanted sex and that they were pressured to send sexual or naked photos of themselves.

In the study, published online Wednesday in the Journal of Youth and Adolescence, researchers concluded that digital technology was not the cause of abuse by teens in a relationship, but that it provided a platform for abuse, often outside the view of adults.