Related Experiment Video

Updated: Aug 29, 2026

The Cultivation, Growth, and Viability of Lactic Acid Bacteria: A Quality Control Perspective
04:40

The Cultivation, Growth, and Viability of Lactic Acid Bacteria: A Quality Control Perspective

Published on: June 16, 2022

Exploring the links between quality assurance and laboratory resources. An audit-based study

Navjeevan Singh1, Aru Panwar, Vipin Fazal Masih

  • 1Cytopathology Section, Department of Pathology, University College of Medical Sciences, Guru Tegh Bahadur Hospital, Delhi, India.

Acta Cytologica
|December 17, 2003
PubMed

Insights

Implementing corrective measures significantly improved Ziehl-Neelsen (Z-N) staining for acid-fast bacilli (AFB) detection in cytology. This quality assurance initiative enhanced diagnostic accuracy for tuberculosis, benefiting laboratory workflow and personnel performance.

Area of Science:

  • Medical Laboratory Science
  • Microbiology
  • Cytopathology

Background:

  • Ziehl-Neelsen (Z-N) staining is crucial for diagnosing tuberculosis (TB) in cytology.
  • Quality assurance is essential to maintain the accuracy of Z-N staining.
  • Previous laboratory practices may have led to suboptimal diagnostic yields.

Purpose of the Study:

  • To identify and resolve issues affecting Ziehl-Neelsen (Z-N) staining quality.
  • To improve the accuracy of acid-fast bacillus (AFB) detection in fine needle aspiration cytology.
  • To enhance overall laboratory quality assurance for TB diagnostics.

Main Methods:

  • An audit-based quality assurance study was conducted on 1,421 patients with suspected tubercular lymphadenopathy.
  • Laboratory practices for Z-N smear selection were evaluated over an 8-month period (Group 1).
  • A two-step corrective intervention was implemented and assessed over 2 months (Group 2), with statistical analysis using the chi-squared test.

Main Results:

  • In Group 1 (n=1,172), 368 diagnoses were not tuberculosis, and overall AFB positivity was 42%.
  • Following corrective measures in Group 2 (n=249), AFB positivity dramatically increased to 89%.
  • The observed improvement in AFB positivity was statistically significant (P < .0001).

Conclusions:

  • Laboratory quality assurance issues directly impact the effectiveness of Z-N staining.
  • Addressing routine laboratory problems yields substantial benefits for personnel, resource management, and workflow efficiency.
  • The implemented corrective measures significantly enhanced the diagnostic yield of AFB detection through Z-N staining.
Abstract

Related Concept Videos

Quality Assurance01:19

Quality Assurance

Quality assurance is the overarching term used to describe the activities employed to ensure the proper performance of a system. These activities can be classified into three categories: quality control, quality assessment, and internal corrective measures. Typically, these activities work cyclically: quality control is performed before and during the analysis, while quality assessment occurs during and after the investigation. Internal corrective measures are implemented based on the findings...
Quality Control01:05

Quality Control

Quality control is one of the three cyclical quality assurance activities that help keep a system under statistical control. Typical quality control activities include creating quality control charts, conducting proficiency testing, and documenting and archiving results.
Quality control helps track data, visualize trends, and identify variations, making it easier to detect deviations that may affect the accuracy of an analysis. One way to do this is by generating a quality control chart, which...
Data Validation01:15

Data Validation

Method validation is a crucial process in analytical chemistry designed to confirm that a given method consistently produces reliable and high-quality results. This process is essential when a method is applied to different sample matrices or when procedural modifications are made, ensuring that the results meet acceptable standards across various applications.
Key parameters for method validation include:
Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches01:23

Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches

Biopharmaceutical studies constitute a vital field aiming to enhance drug delivery methods and refine therapeutic approaches, drawing upon diverse interdisciplinary knowledge. In research methodologies, the choice between controlled and non-controlled studies significantly influences the study's reliability and accuracy.
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast, controlled...
Introduction to Statistical Process Control01:15

Introduction to Statistical Process Control

Statistical Process Control (SPC) is a method used to monitor and control quality within processes, particularly in manufacturing and service delivery, by employing statistical methods. SPC aims to distinguish between natural (common cause) variation and variation due to specific changes or events (special cause), allowing for timely improvements and sustained quality. The control chart, a pivotal tool in SPC, visually displays data over time alongside a central line of upper and lower control...
Systematic Error: Methodological and Sampling Errors01:15

Systematic Error: Methodological and Sampling Errors

In the case of systematic errors, the sources can be identified, and the errors can be subsequently minimized by addressing these sources. According to the source, systematic errors can be divided into sampling, instrumental, methodological, and personal errors.
Sampling errors originate from improper sampling methods or the wrong sample population. These errors can be minimized by refining the sampling strategy. Defective instruments or faulty calibrations are the sources of instrumental...