Concerned about Change in lab values.

I have gone through 3 d dimer test all due to random check, 2 from local lab and one from central lab With values and date Done from Local lab: 1 jun (d dimer - .62) 2 jun (d dimer - 1.7 ; crp- 6) After single dose of apixaban 2.5 (13 hour prior to test)and methylprednisolone 8mg ( 3 hour prior to test) Gone for test to cross check Done from Central lab: 3 Jun ( d dimer -.25;  crp-  .91) A single dose may change dimer from (1.7 - .25 ) Can this be possible? Can there be technical sensitivity in this test? Whom shall I trust central lab or local ? Presently consuming 2.5 mg OD Shall I unnecessaryly consume apixaban ? There where no symptoms and test was randomly done!! Which lab shall I follow up and how long shall i go for next test without medication?