Skip to main content

Measuring Completeness: Understanding the PDCI Metric

· 3 min read

We've all been there, staring at thousands of records and wondering where to start. Cleaning data can often feel like a task that never ends, especially when you're juggling missing dates and coordinates. If that sounds familiar, you're definitely not alone!

That's where the Passport Data Completeness Index (PDCI) comes to the rescue.

What exactly is PDCI?​

Think of the PDCI as a friendly little score from 0 to 10. It gives you a quick snapshot of how complete an accession's passport data actually is, so you don't have to guess.

One thing to keep in mind: the PDCI measures presence, not correctness. For example, a record might hit a perfect 10 because every field is filled, even if there's a typo hidden in there. The PDCI doesn't tell you if the data is right, just that it's there.

Not All Fields Are Created Equal​

The best part about the PDCI is that it's context-aware.

It understands that a wild accession needs different information than a modern cultivar. For a wild sample, coordinates and collection dates are the stars of the show. For a cultivar, we care more about the breeder's name and the pedigree. Because the PDCI weights descriptors based on the accession's biological status (SAMPSTAT), every record can reach that perfect 10, whether it's a landrace or a breeding line.

How to Use PDCI to Improve Your Collection​

When you're looking at your collection's PDCI distribution, you might be tempted to just chase the zeros. But here's a pro-tip for making your curation a bit more rewarding:

  • Avoid the extremes: Records with very low scores might be missing information that's unfortunately gone for good. On the other hand, those with very high scores are already in great shape.
  • Target the "Middle": This is where the magic happens! You'll often find the most "improvement potential" in intermediate scores. These are the records where a bit of digging through the archives can really boost the value of your data.
  • Spot Patterns: If all your wild accessions have low PDCI but your landraces are high, you've just found your target; it's likely a gap in your collecting-site data.

Curation is a Journey​

At Genesys, we view the PDCI as a helpful diagnostic tool rather than a final destination. By tracking your average score over time, you can see your hard work paying off in real-time.

Is your collection as complete as it could be? We'd love for you to head over to Genesys, check your scores, and start your own journey toward a 10! And if you're one of our data providers, you can find a more detailed deep-dive in our curation and validation guide.