“…Most commonly, instruments included vein visibility (88%) and palpability (69%) as key indicators for identifying DIVA. Vein visibility was quantified as ‘not visible’, 13,29,35,43 ‘few visible’, 23,44 visible ‘with tourniquet’, 37,39 ‘vein easily seen’, 30 or in degrees of visibility 4,11,40,42 . Similarly, palpability was quantified as ‘not palpable’, 13,29,35,43 ‘few palpable’, 23,44 palpable ‘with tourniquet’ 37,39 or as degrees of palpability 4,11,40,42 .…”