Victimization studies attempt to fill in where police reports are missing by asking people if they have been a victim of a crime in a given year, reported or not. The National Crime Victimization Survey (NCVS) is the primary source of information on criminal victimization in the United States. The NCVS helps fill in gaps that the UCR and NIBRS cannot fill in because that data is only crimes known to police. Every year the U.S. Census Bureau administers the survey and gathers data on frequency, characteristics, and consequences of criminal victimization from approximately 135,000 households, composed of nearly 225,000 persons. The NCVS collects information on nonfatal personal crimes (i.e., rape or sexual assault, robbery, aggravated and simple assault, and personal larceny) and household property crimes (i.e., burglary, motor vehicle theft, and other theft) both reported and not reported to police.  It is important to help fill in the gap of the dark figure of crime previously discussed.
The NCVS collects information on age, sex, race and Hispanic origin, marital status, education level, and income, and whether they experienced victimization. Additionally, the NCVS collects information about the offender about age, race and Hispanic origin, sex, and victim-offender relationship, characteristics of the crime (e.g., time and place of occurrence, use of weapons, nature of injury, and economic consequences), whether the crime get reported to police, reason(s) the crime was or do not get reported, and victim experiences with the criminal justice system.  See the link below to explore the NCVS https://www.bjs.gov/index.cfm?ty=dcdetail&iid=245
See the report below on findings of repeat victimization from the NCVS: https://www.bjs.gov/index.cfm?ty=pbdetail&iid=6046
Go to the NCVS page and use the analysis tool that allows you to examine the National Crime Victimization Survey (NCVS) data on both violent and property victimization. You can select the victim, household, and incident characteristics.
You can instantly generate tables with national estimates of the numbers, rates, and percentages of victimization from 1993 to the most recent year that NCVS data are available. The pre-set Quick Tables show you trends in crime and reporting to the police. If you would like more detail, use the Custom Tables analyze victimization by excellent characteristics.
As with any data source, there are challenges and limitations to victimization surveys. Respondents may have issues recalling victimization, which can lead to underreporting or overreporting. If an individual was traumatized the event may blur together, and it may have occurred in 2017 rather than 2018, but gets reported as 2018. Other times respondents may lie or omit information for various reasons such as shame, fear, confusion, and a lack of trust. If the respondent is uncomfortable with the interviewers, they may not want to tell them that their partner abused them out of fear it will get reported to police. However, methodological techniques can attempt to minimize these challenges buy bounding to mitigate the chances of this happening.