Reading Results
How to interpret the results, evidence and counts shown across PlasticDB.
Degradation results: positive, negative, inconclusive
Every entry in PlasticDB comes from an experiment in which a microorganism or a protein was tested against a plastic. PlasticDB records the reported outcome of that test, not just the fact that it happened. Each test has one of three results:
- Positive — degradation of the plastic was observed.
- Inconclusive — the test was run but the outcome was ambiguous or could not be clearly interpreted.
- Negative — the organism or protein was tested and no degradation activity was detected.
Negative and inconclusive results are valuable: knowing that a candidate did not degrade a plastic helps avoid repeated experiments and sharpens the picture of what truly works. Because of this, PlasticDB is careful never to present a negative result as if it were evidence of degradation.
“Degrading”, “inconclusive”, “no activity”
On a plastic page, microorganisms and proteins are split into separate tables by how they performed against that plastic:
| Table | Meaning |
|---|---|
| Degrading | At least one study reported a positive result. |
| Inconclusive | No positive result, but at least one inconclusive test. |
| Tested — No activity | Tested one or more times, and every result was negative. |
An actor is placed in the best bucket it qualifies for: a single positive result is enough to list it as degrading, even if other papers disagree.
When papers disagree
Sometimes different studies report different outcomes for the same pairing. The small badges next to a result tally the supporting papers on each side:
Positive 3+ 1? 2−
This example means three papers reported degradation, one was inconclusive, and two reported no activity. On microorganism and protein pages a pairing with more than one polarity is flagged Mixed so you can see the disagreement at a glance.
What the counts mean
Headline counts across the site — the “Degrading Microorganisms” / “Degrading Proteins” numbers on plastic pages, the per-plastic counts in the plastics table, the totals on the statistics page, and the country map — count degraders only: distinct microorganisms or proteins with at least one positive result.
Entities whose only evidence is negative or inconclusive are not included in these totals; they still appear in the relevant “inconclusive” or “tested — no activity” tables on the plastic page, and every record remains searchable.
The evidence behind each entry
Expand the Evidence section on any microorganism, protein or plastic page to see the underlying tests — one row per experiment with its result, the source paper, and a drawer of experimental conditions and observations.
Every result in PlasticDB is traceable to published literature with a DOI. Unlike databases that include computationally predicted activity, each entry here is backed by a published experiment. The Data Model page explains how these records connect, and the About page covers data provenance.