Data quality

Some important things to know:

• Quality does not make sense for itself: quality depends on usages.
• No database at all can pretend to zero-default.
• With more than 2 600 000 products, there are quality concerns: our goal is to lower the impacts of the issues.

Data quality: how to help?

Nutrition values issues

Open Food Facts identifies some issues related to nutrition values. Some of them are very easy to solve:

• Energy value in kcal greater than in kJ
• Nutrition Salt is higher than 100g per 100g
• Carbohydrate is higher than 100g per 100g
• Fat is higher than 100g per 100g

Nutri-Score quality

Some products now have Nutri-Score printed on the front of pack. Some differs from our Nutri-Score calculation. We should take care about that:

• Nutri-Score printed A but calculated E
• Nutri-Score printed A but calculated D
• Nutri-Score printed A but calculated C
• Nutri-Score printed E but calculated A
• Nutri-Score printed E but calculated B
• Nutri-Score printed E but calculated C
• Nutri-Score printed D but calculated A
• Nutri-Score printed D but calculated B
• Nutri-Score printed D but calculated C
• Nutri-Score printed B but calculated E
• Nutri-Score printed B but calculated D
• Nutri-Score printed B but calculated C

There are many reasons why it can differ:

• the label in Open Food Facts does not represent the label printed on the package (easy to solve)
• the label is correct, but our calculation doesn't provide the same result:
  • check the category,
  • then check the nutrition facts: the issue is sometimes the lack of "fibers" information or the lack of "Fruits, vegetables, nuts and rapeseed, walnut and olive oils" percentage.
• it can be a software issue (quite rare but possible).

Issue	Rationale	How to fix
The Nutri-Score displayed by the producer is different from the Nutri-Score Open Food Facts computes	The label in Open Food Facts does not represent the label printed on the package	Change the label
idem	The category is wrong	Change the category and see if it's modifying the Nutri-Score
idem	The nutrition facts are wrong	Update it If the product's nutrition facts has evolved from a previous version, you can add it to the products whose recipe has changed or even better, if it's the case, the products with a Nutri-Score that has improved over time.

Cleaning up the consequences of an old Android bug

The word "Loading…" replaced the correct product name. 99% of phones have been updated with the fix, but we still have some unfixed products.

• Italian
• English
• French
• German

Non-Food Products

Some people are adding products which are not food: beauty products, books, pet food, etc. These products have to be moved to Open Food Facts side projects. Our AI (artificial intelligence) already identifies many cases. These cases are published in the #bot-image-alerts channel on our slack space.

How to move these products?

• identify a product in the #bot-image-alerts channel
• clic on the link after "edit:"
• if you have the rights to so, you will see "If the barcode is not correct, please correct it here"
  • enter "obf" to move beauty products to Open Beauty Facts
  • enter "opff" to move products to Open Pet Food Facts
  • enter "opf" to move products to Open Product Facts
• save (if "A product already exists with the new code" message appear, move it manually, and delete it)
• in #bot-image-alerts channel, annotate the product with a "checked" icon to tell others that the product has been moved

Data quality measurement

We have started an initiative to measure and publish continuously some data quality stats. We have created a specific page dedicated to data quality stats.

Helping technically with data quality

• If you have technical skills, you can also do your part for data quality. Head over to our tracking issue on GitHub