Reducing sample rejection in Durban, South Africa

Rejections of clinical chemistry specimens delays the availability of results, which may impact patient management. The study aims to measure sample rejection rate, identify reasons for sample rejection, evaluate the effect of a campaign to reduce rejection rates and discover which clinical units produced the most insufficient specimen.

The study measured specimen rejection rates and the contributions of different rejection reasons in calendar 2016 and April 2018-March 2019. The study undertook a 7-intervention campaign to reduce specimen rejection during the 2018-2019 intervention period. It compared rejections rates, number of months with rejection rates ≤1.2%, and distribution of rejection reasons between the two year-long intervals. The study also determined the origin for specimens rejected for the most common rejection reason during one month in the second period.

The overall rejection rate fell significantly from 1.4% in pre-intervention period to 1.2% in the intervention period. The number of months with rejection rates within the target range increased significantly from 2 in the post-intervention period to 6 in the intervention period. Insufficient, hemolysed, and 'too-old' specimen decreased significantly, however, insufficient specimen remained the most frequent rejection reason. In February 2019, one-third of all insufficient specimen came from neonatal units and 24% from the pediatric units.

Interventions decreased significantly both overall and monthly rejection rates above target levels. Insufficient, hemolysed, 'too-old' specimen, became significantly less frequent, however, insufficient specimen remained the most frequent rejection reason. Over a month, most insufficient specimen came from neonatal and pediatric sites.