Suggested use case: how to use barcodes to keep data secure

One question we often get from clients is how best to maintain anonymity of the people they’re interviewing and tracking via Secure Data Kit. The answer we almost always come back to a relatively straightforward solution: bar codes. Here’s how it works:

  1. When setting up your forms, instead of putting in any personally identifiable information into your form, you’ll simply put “bar_code_id” (or something similar)

  2. You’ll set up a system **external** to SDK that tracks the personal information and the bar_code_id. Personal information might be a name, address, a village, a community, etc. These two systems will remain separated by the bar_code_id will act as what we might call a “foreign key”: a way for the two systems to be linked at some point down the road.

  3. At this point you can either print bar codes (if you’re sending lab samples off) or you can auto generate a bar code id via any number of bar code generation tools.

  4. When using Secure Data Kit, you can open a 3rd party tool such as Barcode Scanner in the google play store to scan the bar code. This will auto populate the form with the bar code id. Or you can manually enter the bar code id. Either works.

  5. You’ll input any information you’d like to keep outside of SDK into another tool and as previously mentioned, the bar code id into SDK.


This relatively straightforward process is one way to ensure that personally identifiable information never makes it into the system of record. It is worth noting that we encrypt all data in transit as well as at rest so you could absolutely use us to store your PII.