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Frequencies and causes of pre-analytical errors in a tertiary care hospital laboratory in Saudi Arabia
Nasser Thufayl Alenezy1, Shoukat Ali Arain2, Amir Omair3
1From the Clinical Laboratory, Diriyah Hospital, Riyadh, Saudi Arabia.
Background:
Errors in clinical laboratory tests can have a detrimental effect on healthcare delivery. The pre-analytical phase accounts for most laboratory errors, known as pre-analytical errors (PAEs).
Objective:
This study investigated the causes and frequencies of PAEs occurring within a laboratory of a tertiary care hospital.
Design:
A single-center, retrospective, observational study.
Setting:
King Abdul-Aziz Specialist Hospital, Taif, Saudi Arabia.
Materials And Methods:
All laboratory test orders and repeated or rejected specimens in the Laboratory Information System (LIS) during 2021. The data consisted of the types of PAEs, their distribution across laboratory sections, the patient source among hospital departments, and the working shift during which PAEs were recorded.
Main Outcome Measures:
The causes and frequencies of PAEs across laboratory sections, hospital departments, and work shifts were analyzed.
Sample Size:
2104 PAEs from a total of 3 346 199 test orders.
Results:
Of the 3 346 199 test orders, 3137 were recorded as either repeated or rejected. Of these, 2104 (67.1%) were attributed to PAEs, representing a rate of 0.063% (95% CI: 0.060-0.066%) of the total test orders. 'Clotted specimens' (32%) and 'insufficient quantity' (31%) were the most frequent PAEs. Significant differences were identified in the error rate and type of PAEs across laboratory sections, hospital departments, and working shifts (P<.001 for each). The highest error rate was in the blood bank (0.4%). The hematology section accounted for the largest proportion of errors (48.4%). Most PAEs were test orders from the inpatient department (47.3%), with a majority occurring in the morning shift (58.2%).
Conclusion:
Our study revealed a low overall PAE rate of 0.063%. 'Clotted specimens' and 'insufficient quantity' were the most frequent errors. Importantly, we identified significant differences in the types of PAEs across laboratory sections, hospital departments, and working shifts, indicating their multifaceted and context-dependent nature.
Limitations:
A retrospective, single-center study.
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