Accuracy. Does the data describe the reality as it is? Accurate data describes the object represented in the database with the right values, both in form and format. A typical mistake regarding format accuracy is recording dates with wrong format. If the database format is MM/DD/YYYY and someone registers dates with the DD/MM/YYYY format, the data stored in the database won’t reflect reality correctly. Uniqueness. Is the data recorded with no redundancies? Avoid unnecessary duplication of information as much as possible. As an efficiency principle, each piece of data should be recorded once, which means that the number of objects in the real world matches the number of entities represented in the database. If the database registers victims of violent events by capturing biographical and socioeconomic characteristics, each victim should be recorded once. If the same victim suffers two different violent events and gets registered twice, there will be a duplicity. To ensure uniqueness, each entity —in this example, the victim— is identified with a primary key that can be related with various violent events. Timeliness. Is the data available when it is required? How long does it take from when an event is noticed until its data is properly registered? How much time passess from data collection to database recording? Completeness. Are all the required data items properly recorded? How many blank values are there in the database? Blank values are empty slots in the database, which means that there is no value for a given property. A high percentage of blanks in the same category might be a signal of a broader issue, as misunderstanding of its meaning or need of reformulation. If the database is supposed to help to provide telephonic assistance to victims but the telephone of a victim is not recorded, the database will fail in its mission due to lack of data. Consistency. Are there any contradictions between data? Does the data match across different data stores? If the database registers the victim’s date of birth and, also, the victim’s age within a range of ages, there should be no contradictions between both fields. Validity. Is the data valid according to the indexing rules? Databases often include syntax rules to set the data format, typology and range. Some common data types are text, 5