# How does secondary attributes-matching work?

Matching named entities requires algorithms to determine how data should be matched. In this regard, we distinguish [**name-matching algorithms**](https://developer.screena.ai/#name-matching-algorithms) from **secondary attributes-matching algorithms**.

Matching names requires a **threshold value** between 0 and 100%. This value helps to determine the point where it becomes highly probable that two names are the same.

In addition to name matching, it is also possible to apply specific [**matching algorithms**](https://developer.screena.ai/#algorithms) to secondary attributes (e.g., date of birth, address, nationality). Using secondary attributes-matching algorithms helps to automatically discard irrelevant matches (i.e., false positives) by leveraging more data points than names alone.

{% hint style="info" %}
You can check [Screena Plus endpoints](https://developer.screena.ai/#screena-plus) to find out all secondary attributes available per type of entity (i.e., individuals, organizations, vessels).
{% endhint %}

Here is a code example of how to search an individual with date of birth as a secondary attribute.

This request uses the [date-matching algorithm](https://developer.screena.ai/#date-matching-algorithms) `dateOfBirthAlgo` to match dates of birth within the same year:

{% code lineNumbers="true" %}

```json
{
	"queries": [{
		"sourceData": [{
			"names": [{
				"fullName": "Adan Antonio Blanco Rodriguez"
			}],
			"datesOfBirth": [{
				"date": "1968-03-18"
			}]
		}],
		"targetData": [{
			"datasets": [{
				"label": "USA"
			}]
		}],
		"threshold": 0.8,
		"dateOfBirthAlgo": {
			"type": "same_year"
		}
	}]
}
```

{% endcode %}


---

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