Objectives: To determine the rate with which blood collection is successful on the initial phlebotomy encounter, the rate with which laboratory personnel judge specimens unsuitable for analysis, and the practice characteristics associated with fewer unsuccessful collections and fewer rejected specimens.
Design: Clinical laboratories participating in the College of American Pathologists Q-Probes laboratory improvement program prospectively characterized the outcome of outpatient phlebotomies for 3 months or until 20 unsuccessful phlebotomy encounters occurred. By questionnaire, participants provided information about test ordering, patient preparation, and specimen collection.
Setting and participants: Institutions in the United States (n = 202), Canada (n = 4), Australia (n = 3), and South Korea (n = 1).
Main outcome measures: Percentage of successful encounters and percentage of unsuitable specimens.
Results: Of 833289 encounters, 829723 were successful. Phlebotomies were unsuccessful because patients were not fasting as directed (32.2%), phlebotomy orders were missing information (22.5%), patients specimens were difficult to draw (13.0%), patients left the collection area before specimens were collected (11.8%), patients were improperly prepared for reasons other than fasting (6.3%), patients presented at the wrong time (3.1%), or for other reasons (11.8%). Only 2153 specimens (0.3%) were unsuitable; these samples were hemolyzed (18.1%), of insufficient quantity (16.0%), clotted (13.4%), lost or not received in the laboratory (11.5%), inadequately labeled (5.8%), at variance with previous or expected results (4.8%), or unacceptable for other reasons (31.1%). Facilities staffed by laboratory-administered phlebotomists reported higher success rates than facilities staffed by nonlaboratory-administered phlebotomists (P =.002).
Conclusions: Most outpatient phlebotomy encounters are successful and result in specimens suitable for laboratory analysis.