Which microcollection tube should be filled last for capillary blood collection?

In capillary blood collection, the microcollection tube that should be filled last is typically the tube containing an additive, such as a gel separator or anticoagulant. This helps to prevent contamination of the sample with other additives from previously filled tubes. Often, the tube for hematology tests, which does not contain additives, is filled first, followed by tubes for biochemistry or other analyses.