### Duplicate patient IDs and collision detection

There are several scenarios that can lead to having duplicate patient IDs. The action you need to take depends on several factors:

Scenario 1: If you are merging two distinct databases that contain the same patient IDs, but these IDs belong to different patients:

• You need to turn on the Auto-increment patient identifier on collision setting in the Merge settings form.

1. To access the Merge settings form, click Data merge in the main menu, and then click Merge settings.

The default values usually work, but you may need to change these if you are doing multiple merges, for example.

Scenario 2: You really do have some duplicate data with the same patient records occurring more than once.

• In this case, make sure you turn off (clear) the auto-increment setting.

Any duplicates will not be uploaded.

Caution It is possible to get a situation where both scenarios are true in part. If this is the case, you can only make progress by examining each record in turn.

More:

Modifying settings

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