There are several long-term developmental studies, eg Millennium Cohort, which have had to ask such questions to whole populations and are familiar with the ethical problems.

Dear Sarah

Caroline Øverlien is one researcher in Norway that have been working in violence against children. Probably will be helpful to read her work https://www.researchgate.net/profile/Carolina_Overlien

Best

Dear Sarah, Check the CTS-PC of Murray Straus. 

Hi Sarah,

although they are not specifically designed for sexual abuse, you might try the J-NAAP and the LSC-R.

• Jacobs Neglect, Abandonment, and Abuse Protocol (J-NAAP): a self-report measure that assesses traumatic or stressful life events such as loss or abandonment, serious neglect, physical abuse, emotional abuse, and sexual abuse.
• Life Stressor Checklist—Revised (LSC-R):

a self-report measure that assesses traumatic or stressful life events. The measure has a focus on events relevant to women such as abortion, and can also be used with men. The questionnaire includes 30 life events, including experiences with natural disasters, physical or sexual assault, death of a relative, and other events, following a yes/no response format. For endorsed events, respondents are asked to provide: age when event began, age when event ended, belief that they were in harm ("yes" or "no"), and feelings of helplessness ("yes" or "no"). In addition, effect on life and how upsetting event was at the time are rated on a five-point intensity scale (1 = "not at all or never" to 5 = "extremely"). Respondents are asked to identify the three events that currently have the greatest impact on them. 

LSC-R – survey: http://www.ptsd.va.gov/professional/pages/assessments/assessment-pdf/LSC-R.pdf

LSC-R – scoring: http://www.ptsd.va.gov/professional/pages/assessments/assessment-pdf/LSC-R-Scoring.pdf