How are UK Biobank study traits identified in the Genetics Portal?

An Open Targets Genetics Portal user recently contacted the Open Targets helpdesk to ask:

In the Open Targets Platform, NEALE2_6152_9 is given as “Hayfever, allergic rhinitis or eczema | blood clot, dvt, bronchitis, emphysema, asthma, rhinitis, eczema, allergy diagnosed by doctor”. Which condition does this refer to?

Is there a major category called "blood clot, dvt, bronchitis, emphysema, asthma, rhinitis, eczema, allergy diagnosed by doctor” that people could fill in, and an undercategory "Hayfever, allergic rhinitis or eczema” to get more specificity?

How the Portal showcases studies with multiple traits

The study in question is from the UK Biobank (NEALE2_6152). In the Portal, we dissect each study in such a way that our study IDs — in this case, NEALE2_6152_9 — always refer to one of the observed traits.

The UK Biobank reports a number of traits (e.g. blood clot, dvt, bronchitis, emphysema, asthma, rhinitis, eczema, allergy diagnosed by doctor) for NEALE2_6152.

In NEALE2_6152_9, we are only referring to the trait given before the pipe (|): hayfever, allergic rhinitis or eczema.
So for example, NEALE2_6152_7, in the same study, specifically refers to Blood clot in the lung.

In this way, data is annotated on a per trait basis.