/diseases/case-series/filter-options

Returns **distinct filter values** for case-series UIs. Uses the same **camelCase** query parameters as **`GET /diseases/case-series/filter`**. With **no** parameters, a faster path loads options from the full case-series set. With **any** of `disease`, `country`, `startYear`, `endYear`, `setting`, `population`, `parameter`, or `region`, options for each facet are built with that facet’s own filter relaxed. - **`regions`** — Populated only when **`country`** is set and subdivision-level rows exist; items use `region_id` and `region_name`. - **`years`** — Keys are `survey_start_years` and `survey_end_years` (naming mirrors surveys; values are case-series start / derived end years, with publication years merged into the start list). #### **Query parameters** | Name | Description | | --- | --- | | `disease` | Disease id. | | `country` | Country code. | | `startYear` / `endYear` | Year overlap filters. | | `publicationYear` | Exact publication year. | | `setting` | Setting id. | | `population` | Population id. | | `parameter` | Parameter id. | | `region` | Region id. | #### **Response** `data` contains `diseases`, `countries`, `settings`, `populations`, `parameters`, `regions`, `years`. The saved example trims each facet to one item (and a few sample years); live responses list every distinct value.