Analysis of laboratory sample rejections in the pre-analytical stage at an oncology center.

BACKGROUND

Effective patient management depends on the accuracy of laboratory results. Sample collection errors constitute an important reason for repeat collections. This study was conducted at the laboratory diagnostic services of a tertiary care oncology center with a hematopoietic stem cell transplant unit to determine the common causes of sample rejections and see the effects of corrective action.

METHODS

A retrospective, intervention and prospective analysis of the samples rejected from the total samples received in our laboratories, during a nine month period from January to September 2011 was undertaken. Causes of sample rejections were determined and intervention in the form of training relevant staff was instituted.

RESULTS

Out of 32,548 samples received during Jan-Sep 2011, 177 samples (0.54%) were rejected. The most common reasons for rejection in hematology and biochemistry areas were clotted blood specimen (51.2%), improperly labeled specimen containers (14.46%) and hemolyzed blood samples (11.45%). For microbiology these included labeling errors, collection of specimen in wrong containers and specimen collection date and time not being entered, unacceptable specimen source and delayed transit time (18.2% each).

CONCLUSIONS

Directed interventions may help reduce the incidence of sample rejections.