Laboratory quality can be defined as accuracy, reliability and timeliness of reported test results. The laboratory results must be as accurate as possible, all aspects of the laboratory operations must be reliable, and reporting must be timely in order to be useful in a clinical or public health setting1.

Laboratories produce test results that are widely used in clinical and public health settings, and health outcomes depend on the accuracy of the testing and reporting. In order to achieve the highest level of accuracy and reliability, it is essential to perform all processes and procedures in the laboratory in the best possible way. The laboratory is a complex system, involving many steps of activity and many people. The complexity of the system requires that many processes and procedures be performed properly. Therefore, the quality management system model, which looks at the entire system, is very important for achieving good laboratory performance

In India accreditation for medical laboratories is not mandatory. All laboratories only have to register themselves with the health departments in the respective states. The only accreditation agency that is authorized by the central government is the National Accreditation Board for Testing and Calibration of Laboratories (NABL). An estimate shows that there are about one lakh medical diagnostic laboratories are existing in the country. Enquiries reveal that NABL has accredited around 450 medical laboratories (0.45%), with the rest (99.5%) having only registered with the respective state health departments3.

The medical laboratories seeking accreditation from NABL are assessed in accordance with ISO 15189:2012. A laboratory wishing to be accredited by NABL must have a Quality Manual on its Quality System satisfying the requirements as described in the various clauses of ISO 15189:2012 standard. All applications for accreditation shall have to be in accordance with ISO/IEC 17025 or ISO 15189:2012 standard. Implementation of ISO 15189:2012 standards in help the clinical laboratory to show continual improvement, enhance confidence of the staff and to achieve patient satisfaction. So it would be beneficial for any clinical lab in India to get NABL accreditation4.

A quality management system can be defined as coordinated activities to direct and control organization with regard to quality. This definition is used by International Organization for Standardization (ISO) and by the Clinical and Laboratory Standards Institute (CLSI). Both groups are internationally recognized laboratory standards organizations5.

In a quality management system, all aspects of the laboratory operation, including the organizational structure, processes and procedures, need to be addresses to assure quality. There are many procedures and processes that are performed in the laboratory and each of these must be carried out correctly in order to assure accuracy and reliability of testing. An error in any part of the cycle can produce a poor laboratory result. A method of detecting errors at each phase of testing is needed if quality is to be assured6.

ISO standards group laboratory processes into pre-examination, examination and post-examination categories7. Comparable terms in current laboratory use include: pre-analytic, analytic and post-analytic processes; or pre-test, test and post-test processes.

ISO standards group laboratory processes into pre-examination, examination and post-examination categories. Comparable terms in current laboratory use include: pre-analytic, analytic and post-analytic processes; or pre-test, test and post-test processes.

In order to have a functioning quality management system, the structure and management of the laboratory must be organized so that quality policies can be established and implemented. There must be a strong supporting organizational structure—management commitment is crucial—and there must be a mechanism for implementation and monitoring.

The most important laboratory resource is competent, motivated staff. The quality management system addresses many elements of personnel management and oversight, and reminds us of the importance of encouragement and motivation.

A Prospective (Cross-Sectional) study will be conducted in laboratories to evaluate current quality practices in comparison to ISO 15189:2012. The Study will be conducted in clinical Laboratories i.e. Biochemistry, Microbiology and Pathology of Nizam’s Institute of Medical Sciences which is a Tertiary care teaching Hospital.

The gap analysis will be conducted based on laboratory work cycle starting from sample collection to issuing of reports, which includes observation of sample collection rooms, individual Laboratory Process and services and physical verification of all the records/documents for the period of six months related to Quality parameters involved in Laboratory standards.

The entire set of operations that occur in testing is called the path of workflow. The path of workflow begins with the patient and ends in reporting and results interpretation.

A checklist of 33 parameters based on ISO 15189:2012 standards is formulated for assessing the total processes involved in all the three laboratories (Biochemistry, Microbiology, Clinical pathology). The criteria employed to record the findings were “Yes”, “No” as the options. A total of 40 samples will be selected for each investigation considered for study in the individual laboratories (Biochemistry-16, Microbiology-13, Clinical Pathology-7). These 33 parameters were evaluated based on laboratory processes from sample collection to reporting. The data collected were analyzed using SPSS 24.0 where the percentage of the values were drawn and presented in the form of table.

During the study the individual Laboratories and Sample collection rooms (i.e. Biochemistry, Microbiology and Clinical Pathology) will be visited multiple times to observe the collection, processing, Interpretation, documentation and reporting of samples. The gap analysis will be conducted based on laboratory work cycle which is divided in to 2 phase

Data collection and analysis

The data for Gap analysis study will be collected and documented from individual clinical laboratories and sample collection rooms by using data collection form in Microsoft Word document for all the 16 Parameters mentioned above. The collected data of current practices on individual parameter will be compared to ISO 15189 standards (best practices) based on which it will be decided whether the particular Quality parameter is Compliant or Non-Compliant in accordance to ISO 15189: 2012(E), and also possible to derive appropriate suggestions and improvements to meet the standards. The entire study data

will be presented in descriptive statistics based on Gap Analysis

Table 1 shows the analytical parameters used to evaluate 16 investigations (n=16) of 40 samples which represents the                  Compliance and Non-Compliance percentages of parameters against ISO 15189: 2012 standard.

Department of Microbiology

1. Examination Process- Technical Requirement.

1. Scope:

The tests included in the scope of accreditation for Microbiology are:

1. Staining Procedures - Grams stain, Z-N Stain, GEIMA'S, Indian ink preparation Wet film for Ova/Cyct, Tzanck smear, Dark field Microscopy
2. Aerobic Culture & Sensitivity test on various body fluids
3. Blood Culture & Sensitivity - both Aerobic and Anaerobic
4. Catheters/Tips/Shunts-Arterial cannula -Cavofix tip - Central Line Tip -Endotracheal tube -Ventricular Shunt
5. Fluid Aspirates - Bronchial wash - Bronchial Aspirate - Trans Bronchial - C.S.F Drain Fluid - Synovial fluid - Tracheal Aspirate - Tears
6. Aerobic and Anaerobic culture and sensitivity -Ascitic Fluid - Peritoneal fluid - bile Pericardial fluid - Pleural fluid - bone Marrow - Pus – Semen.
7. Tissue (Aerobic, Anaerobic fungal & TB culture)
8. Faeces Culture Aerobic culture and Sensitivity
9. Skin/Hair/Nails for Fungus
10. Sputum Aerobic Aerobic culture and Sensitivity
11. Swabs Aerobic culture and Sensitivity -WOUND - Eye/Conjunctiva - Ear -Nasal Throat-Cervical -Urethral -Any other (Specify)
12. Urine Clean catch - Catheter Catch - Cystoscopic - Suprapubic
13. Mantoux Test.
14. Infrastructure Space:
15. The laboratory is not been designed for the efficiency of its operation, to optimize the comfort of its occupants and to minimize the risk of injury and occupational illness to patients, employees and visitors There is no proper partition for the Adjacent procedures(Bacteriological, Myco-bacteriological and Mycology).

3. Accommodation and Environment:
4. Culture Media are prepared in the separate area.
5. The Microbiology department (only automated equipment room) is Air-Conditioned and functions for 24 Hours. Temperature monitoring is not being done for the entire laboratory i.e. daily in the morning or evening.
6. Temperature monitoring is being done for the Refrigerators and Deep Freezers i.e. daily in the morning or evening.
7. The microbiology department is not equipped with Fire Extinguisher.
8. Technicians were wearing Lab coats, face mask and Disposable Safety Gloves while processing the test samples.
9. Facilities like hands-free eye wash is not available.
10. Currently, power cords and power plugs in the laboratory are not identified.
11. There is no system of recording and reporting minor accidents / incidents (electrical, fire, fall, needle prick, etc.,) taking place in the laboratory.

4. Equipment:

The following Equipment’s are available in the Medical Laboratory:

• Bacteriology, Myco- Bacteriology and Mycology
• Bio satety hood Level II A (3 No)

2. BacTec Blood culture analyzer (2 no)
3. Incubator (MuItl cabinet)
4. Autoclave (2No)
5. BOD incubator (Multl Cabinet)
6. Hot air oven
7. Deep Freezer (Multi Cabinet)
8. Weighing balance
9. Parasitology
10. Binocular Microscope - 3 Nos
11. Florescent Microscope -1 Nos
12. Digital Microscope with camera-1 no
13. At present sample processing done by using Biosafety cabinet - Level II A which is not acceptable.
14. Equipment Maintenance Log is not available for the Bio safety cabinet. Equipment used in the laboratory are not labeled and identified.
15. There are no instructions regarding the operation of the major equipment’s.
16. Training certificate on the operation & maintenance of automated equipment’s (Bact alert) is not available for all staff.
17. Equipment Breakdown / maintenance record is maintained but some of the information are not recorded as required by ISO 15189:2012 requirements.

5. Calibration:
   1. Calibration certificate is not available for Bac Alert Systems, Autoclave (pressure gauge needs to be calibrated), Bio safety hoods, Centrifuge, Refrigerator, deep freezer (thermometer needs to be calibrated) & Micropipettes.

6. Calibration Frequency:

1. Frequency of calibration as per ISO requirements
   1. Centrifuge - once in six month
   2. Water bath - once in six month
   3. Incubator - once in six month
   4. Fridge - Once in a year
   5. Microscope - Yearly calibration / Service for every 6 months
   6. Bio safety cabinet - Once in a year
   7. Autoclave - Once in a year
   8. Hot Air Oven - Once in a year
   9. Weighing balance - Once in a year
   10. Micropipettes - Once in a year

7. Sample Receiving:

1. Sample receipt time is not recorded in the Bacteriology, Mycology & Myco Bacteriology registers

8. Testing Methodologies:
9. Only validated and approved test methodologies are used for various stains and C & S tests. Antibiotic sensitivity results interpretation is based on BSAC guidelines.
10. 6 Ab discs are placed in every plate (90 mm) during routine & QC testing.
11. The actual size zone of inhibition (in mm) obtained for Antibiotic sensitivity is not recorded in the bacteriology results register.
12. All Culture Media are prepared in house. They are given a batch number but the pH of the media not identified in the Media register.
13. A bench manual is not available for the technical staff on the work table.
14. Non-disposable inoculation loops are being used which need be calibrated whenever a new lot is put in to use.
15. At present all individual test results are not being approved by the HOD/designee but the technical staff that has processed the sample is not identified.

9. Internal Quality Control:
10. . At present antibiotics are subjected to QC check every 15days but the Lot No and Expiry date Ab discs checked for QC is not recorded in the Ab QC Register.
11. There is no practice of monitoring the sterility of laminar air flow chamber.
12. 10% of every batch of media prepared in house is subjected to QC check using of strains with negative and positive controls and the results recorded.
13. Details of media prepared are recorded in the Media Sterility Register. The pH of media is not checked using pH paper after preparation.
14. 10% of media prepared is subjected to sterility and QC check before being put in to routine use.
15. At present effectiveness of autoclaving is checked using thermal indicator strips only. Biological indicators for checking the effectiveness is not used.

10. External Quality Assurance Scheme (EQAS):
11. At present the lab participate regularly in EQAS / PT program for Microbiology.
12. EQAS samples should not be given special treatment and should be processed in between patient samples.
13. EQAS samples have to be processed in between patient samples. Evidence of having done so to be made available. The details of processing of EQAS samples have to be recorded.

1. post-examination process: Technical Requirement

1. Reporting of Results:
   1. After approval of individual tests results a test report is generated in the department which is signed by the authorized signatory
   2. All positive are considered critical but there is no document for critical alert values for all parameters.
   3. The lab informs the referral Doctor regarding critical results that are obtained but there is no traceability for the same.
   4. Also the department should randomly monitor TAT (Turn Around Time) of tests on a daily basis by randomly taking 1 request and tracing the time taken from Sample Receiving to generation of Test Reports/Preservation Certificate.

2. Test Report Format:

It is mandatory that the laboratory generate a final Test Report and should be readily available for the users of the laboratory upon request as per the requirement of ISO 15189:2012.

3. Bio-Safety and Waste Management:
4. Color coded system of segregation and disposal of waste is being practiced and charts are displayed but the containers are not used properly.
5. Yellow bag was not available in the department. Makeshift containers (used reagent containers) are being used for work bench hypochlorite solutions but are not identified with proper labeling. All technical / housekeeping staff are not aware of the preparation of the hypochlorite solution from the commercially available Hypochlorite solution.
6. The lab staff is not aware whether the biomedical waste is disposed in house or through an external agency.
7. Practice of disposing the waste using color coded bags was not appropriate.

Table 2 shows the analytical parameters used to evaluate 13 investigations (n=13) of 40 samples which represents the Compliance and Non-Compliance percentages of parameters against ISO 15189: 2012 standard

Department of Clinical Pathology

1. Examination Process- Technical Requirement

1. Scope:
2. The department works 24 hours and 7 days a week and receives more than 100 samples per day.
3. Routine urine analysis by Dip stick Method.
4. Routine urine analysis by Manual Method.
5. Urine deposit by manual method.
6. Urine Metachromatic Granules
7. Stool - Reducing Substances
8. Stool occult Blood
9. Semen Analysis

2. Personnel Qualification:

1. Authorized signatory available and they are qualified to sign all reports as per ISO 15189 document (Specific criteria for Accreditation of Medical Laboratories).
2. All technical staff possesses the requisite qualification (B.Sc./D.M.LT) and satisfies the qualification norms as per ISO 15189 document "Specific criteria for accreditation of medical laboratories.

3. Infrastructure Space:
4. Urine examination is done in a separate room.
5. The space is sufficient for performing Clinical Pathology tests.

4. Accommodation & Environment:
5. The laboratory is not Air-Conditioned and the temperature is not monitored in the department.
6. There is no First Aid box available in the department to meet the emergency and accidents.
7. Fire Extinguisher is not available in the department and the lab staffs are not aware of the usage of Fire Extinguisher.
8. At present areas in the department are not differentiated as Infective and Non- Infective areas.
9. Currently, all the laboratory staffs are wearing street shoes/slippers inside the laboratory.
10. There is no system of recording and reporting minor accidents/ incidents (electrical, fire, fall, needle prick, etc.) taking place in the laboratory.
11. At present reference materials (atlases, charts or photomicrographs) are not available and displayed to assist in the identification of routine microscopic examination.

5. Equipment’s:

The following Equipment’s are available in the Clinical pathology department.

1. Light Microscopes
2. Remi Centrifuge
   1. None of the equipment’s used in the department are labeled and identified.

6. Calibration and Calibration Frequency:

1. Calibration certificate is not available for Remi Centrifuge.
2. Currently Microscopes are cleaned and there is no documentary evidence.
3. Suggested frequency of calibration as per requirements.

Centrifuge - once in six month

Microscope - Service Report for every 6 months

7. Sample Collection and Labeling:
8. Capped disposable plastic containers are used for collection of urine, stool and semen samples.
9. The sample labeled manually Patient name, Lab No., Patient Hospital No., Ward No in case of IP.
10. A Reference Number is created for all patients received at the Front Office which is a running number. When patient comes for the second time different Reference Number is given. There is no traceability of patient's history.
11. Samples are received from Collection center (both IP & OP) which is near the laboratory within Hospital Premises. The technicians or person in charge in the department for receiving samples are entering the sample Received Time properly in the Register (Both for IP and OP).
12. It was observed that the samples are submitted with bare hands by the Health Care Assistants to the Sample Receiving Area, and the same was received without gloves.
13. At present stool samples are received from collection area by the department attender for OP. For IP the stool samples are received by the department from Ward Nurses and Attenders.
14. Semen samples are received directly from the Patients by the department. There is no written instruction for semen sample collecting.
15. Samples are sometimes rejected but Details of Samples rejected are not available.
16. There is no proper transport of samples from collection area to laboratories.
17. Samples are transported in trays from the collection area to the concerned departments.

8. Testing Methodologies:
9. There is no traceability of time of processing of samples
10. The department has a practice of confirming all positive results for Routine urine analysis by manual methods but documentation for the same was not available.
11. The department has a practice of confirming all positive results for Occult blood and reducing sugar for Stool analysis by manual methods but documentation for the same was not available.
12. Urgent requests are communicated orally or through telephone to the laboratory and by indicating as urgent request in the test requisition form (TRF).
13. The lab has the practice of repeating Clinical Pathology Tests and records only the repeated values/results in the Clinical Pathology work book. At present the department does not maintain repeat test register.
14. The technical staff that processed the sample is not identified. Technicians are not authorized to approve test results.
15. The Lab informs the referral physicians regarding critical results that are obtained but there is no traceability for the same.
16. At present the processed sample and to be processed samples are kept together on the work table.
17. At present the department maintains work book for routine Urine and stool examinations separately for IP and OP. The department also maintains workbook for Semen samples for IP/OP. There is no traceability of person who has processed the samples, Time of processing and the time of completion of the test.

9. Internal Quality Control:
10. At present the department does not have the practice of running Positive Control and Negative Control for routine urine analysis. b. Internal Quality Control should be run based on the sample load. The average number of samples received per day is more than 100.
11. Post-Examination Process- Technical Requirement

1. Reporting of Results:
2. The test reports are fed in the computer manually once the technician documents the test report values of the concerned Patient Id. The hard copies of lab reports are approved by the Pathologist.
3. Some OP test reports are delivered by the technicians in the department itself.
4. There is no availability or traceability of Report dispatch Time, Delivered by, Received by etc. in the Report Dispatch Register (IP & OP).
5. There is no availability or traceability of Report dispatch Time, Delivered by, Received by for the reports dispatched by the technician to the out patient directly.
6. There is no monitoring of delayed issue of test reports, which is one of the requirements of the standard (continual improvement).
7. Also the department should randomly monitor TAT (Turn Around Time) of tests on a Daily Basis by randomly taking 1 request and tracing the time taken from Sample Collection to Generation of Test Reports.

2. Sample Storage/Discard:
3. At present the samples (Urine, Stool, & Semen) are discarded as soon as the test is completed.
4. Stool samples are disposed as such into the dustbin provided in the department.

3. Bio Safety and Waste Management:
4. It is ensured that the MOU should be available for Bio-medicat Waste Management. The lab staffs are not aware whether the biomedical waste is disposed in house or through an external agency.
5. Practice of disposing the waste using color coded bags was followed but was not appropriate.
6. At present waste containers with Hypochlorite solution are available, But the container used is not identified with proper labeling. The technical staffs are not aware of the preparation of the hypochlorite or the commercially available percent

Table 3 shows the analytical parameters used to evaluate 7 investigations (n=7) of 40 samples which represents the Compliance and Non-Compliance percentages of parameters against ISO 15189: 2012 standard.

The study on laboratory quality compliance at a tertiary care teaching hospital revealed areas of success and improvement across three departments—Biochemistry, Microbiology, and Clinical Pathology. Out of 33 parameters based on ISO 15189:2012 standards, Biochemistry showed 13 parameters with full compliance, Microbiology demonstrated 10, and Clinical Pathology achieved 9. High compliance was observed in areas like infrastructure, emergency backup, waste disposal, quality assessment, and confidentiality. However, several areas, including internal audits, documentation, equipment calibration, and waste management practices, showed gaps. Recommendations for improvement include enhancing compliance in these areas, implementing routine audits, and strengthening staff training to ensure continuous quality enhancement in laboratory services. Investigate the impact of hormonal therapy on menopausal symptoms, bone density, and cardiovascular health.

Key findings

Significant relief from vasomotor symptoms, improved bone density, and favorable cardiovascular outcomes in HT users.

Newer findings

This study highlights the importance of early HT initiation and suggests cultural and geographic factors may influence outcomes. The study also emphasizes the safety of short-term HT use in Indian women.

Funding: No funding sources

Conflict of interest: None declared

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