Broader / loose matches
When you scroll to the end of a strict result list, a third bucket auto-loads with the same primary filter but everything else relaxed. This is the loose tail.
Why it exists
Strict searches with tight filters and the default "currently recruiting, registered in the last 7 years" cap can return surprisingly little. A patient looking for "first-line EGFR-positive NSCLC trials in Mumbai with osimertinib, Phase 3, recruiting" can easily hit zero. Loose mode keeps you from leaving empty-handed.
What gets relaxed
Loose mode keeps only the highest-priority filter dimension in this fixed order, then drops the rest plus location and the tight defaults:
cancer_site > cancer_subtype > biomarker_required > drug_name > drug_class >
treatment_category > biomarker_expression > line_of_therapy > disease_stage > …
So for the example above (cancer_subtype=nsclc_adenocarcinoma + biomarker_required=EGFR + drug_name=osimertinib + city=Mumbai + line=first_line), the loose tail keeps cancer_subtype=nsclc_adenocarcinoma only, drops everything else, drops the recruiting-only + 7-year-recency + open-site defaults, and asks the database "show me any NSCLC adenocarcinoma trials we have".
Treatment intent stays — patients here are looking for treatment trials, not screening or observational. "Broader, not off-topic."
No repeats
Trials shown in the strict buckets above are never repeated in the loose tail. The frontend sends every shown registry ID as an exclude list; the backend filters them out. So the loose section is purely additive.
When you won't see it
- You have no filters set. Loose == strict; nothing to relax.
- Your only filter is already the highest-priority dimension and you have no location / free-text. Same reason.
- The strict result is small enough to fit on one page in Advanced Search — the trigger fires only on the last page.
- You're in the Guided chat variant. Guided is intake → hand-off; results live in Advanced Search where the loose tail will appear.