Analysis of Pre-Analytical Errors in the Clinical Biochemistry Laboratory of a Tertiary Care Hospital

Abstract

Background: Clinical laboratory investigations are essential for accurate diagnosis and patient management. Among the phases of the total testing process, the pre-analytical phase is most susceptible to errors, which can compromise test accuracy and patient safety. Identifying and analyzing these errors is vital for improving laboratory quality and healthcare outcomes.

Objectives: To determine the frequency, types, and sources of pre-analytical errors in the Clinical Biochemistry Laboratory of a tertiary care hospital.

Materials and Methods: This retrospective observational study was conducted in the Clinical Biochemistry Laboratory at Bhagwan Mahavir Institute of Medical Sciences, Pawapuri, Nalanda, over a one-year period from January 2024 to December 2024. A total of 20,000 blood samples received for routine biochemical investigations were analyzed. Pre-analytical errors were identified from laboratory records and sample rejection registers and categorized based on the nature and source of error. Data were analyzed using descriptive statistics and expressed as frequencies and percentages.

Results: Out of 20,000 samples analyzed, 1,420 samples were rejected due to pre-analytical errors, yielding an overall error rate of 7.1%. Hemolysis was the most common cause of sample rejection (36.6%), followed by insufficient sample volume (25.4%) and improper or missing labeling (15.5%). The highest proportion of errors originated from inpatient departments (43.7%), followed by outpatient (33.1%) and emergency departments (23.2%). Collection-related errors constituted the majority of pre-analytical errors.

Conclusion: Pre-analytical errors represent a significant challenge in clinical biochemistry laboratories and are largely preventable. Implementation of standardized sample collection protocols, regular staff training, and continuous monitoring of quality indicators can substantially reduce error rates and enhance patient safety.

Keywords: Pre-analytical errors, Clinical biochemistry, Sample rejection, Laboratory quality indicators, Tertiary care hospital