could anybody tell me how to understand the following sentence? It is taken from a questionnaire in a clinical study and I suppose it is UK English. I am confused about "through". Does it mean that the screening was completed on/during the 4-week follow-up visit?
The sentence is: Record all medications including antibiotics and bronchodilators, vitamins and supplements that the subject has taken within 30 days before Screening through the 4-week Follow-up Visit.
I think the screening is a single event and 4 weeks later there is a visit, so through links the two- thirty days before + 4 weeks after.