Good Clinical Laboratory Practices Improved Proficiency
Testing Performance at Clinical Trials Centers in Ghana
and Burkina Faso
Faisal Ibrahim1*, David Dosoo2, Karl C. Kronmann1, Issa Ouedraogo3, Thomas Anyorigiya4,
Haruna Abdul5, Sirima Sodiomon3, Seth Owusu-Agyei2, Kwadwo Koram5
1 United States Naval Medical Research Unit -3 Ghana Detachment, Accra, Ghana, 2 Kintampo Health Research Center, Kintampo, Ghana, 3 Center National de Recherche
et de Formation sur le Paludisme, Ouagadougou, Burkina Faso, 4 Navrongo Health Research Center, Navrongo, Ghana, 5 Noguchi Memorial Institute for Medical Research,
Legon, Ghana
Abstract
Background: The recent drive towards accreditation of clinical laboratories in Africa by the World Health Organization –
Regional Office for Africa (WHO-AFRO) and the U.S Government is a historic step to strengthen health systems, provide
better results for patients and an improved quality of results for clinical trials. Enrollment in approved proficiency testing
(PT) programs and maintenance of satisfactory performance is vital in the process of accreditation. Passing proficiency
testing surveys has posed a great challenge to many laboratories across sub-Saharan Africa. Our study was aimed at
identifying the causes of unsatisfactory PT results in clinical research laboratories conducting or planning to conduct malaria
vaccine trials sponsored by the National Institutes of Health (NIH).
Methodology: PT reports for 2009 and 2010 from the College of American Pathologists (CAP) for the laboratories were
reviewed as part of the process. Errors accounting for unsatisfactory results were classified into clerical, methodological,
technical, problem with PT materials, and random errors. A training program on good clinical laboratory practices (GCLP)
was developed for each center to address areas for improvement.
Results: The major cause of PT failure in the four centers was methodological. The application of GCLP improved the
success rate in the PT surveys from 58% in 2009 to 88% in 2010. It also decreased the error rate on PT by 35%.
Conclusion: A previous report from the CAP- PT participating laboratories indicated that the major causes of error were
clerical. These types of errors were predominantly made in laboratories in the US, with much more experience in quality
control, and varied significantly from what we found. In our centers in sub-Saharan Africa, methodological errors, and not
clerical errors, accounted for the vast majority of errors. A process was started for continuous improvement which has
decreased methodological errors by 35%, but more improvement is needed.
Citation: Ibrahim F, Dosoo D, Kronmann KC, Ouedraogo I, Anyorigiya T, et al. (2012) Good Clinical Laboratory Practices Improved Proficiency Testing Performance
at Clinical Trials Centers in Ghana and Burkina Faso. PLoS ONE 7(6): e39098. doi:10.1371/journal.pone.0039098
Editor: Clive Shiff, Johns Hopkins University, United States of America
Received November 23, 2011; Accepted May 18, 2012; Published June 29, 2012
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for
any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
Funding: This work was supported by the United States National Institutes of Health. The funders had no role in study design, data collection and analysis,
decision to publish, or preparation of the manuscript.
Competing Interests: The authors have declared that no competing interests exist.
* E-mail: faisali40@hotmail.com
Introduction health systems, provide better results for patients, and improve the
quality of results for clinical drugs and vaccines trials. Laboratories
There are, currently, a large number of clinical drugs and across Africa are making progress with the WHO-AFRO step-wise
vaccines trials being conducted in developing countries [1]. approach toward accreditation. Factors that contribute to a
Sponsors often face difficulties in maintaining quality system successful accreditation project are implementation of Good
activities in resource limited settings, and in locations where there Clinical Laboratory Practices (GCLP) and the application of a
are no official government or laboratory network standards, and Quality Management System. This includes the enrollment in
no third party responsible for inspections to maintain compliance approved proficiency testing (PT) programs and maintenance of
[1]. Laboratory auditing by monitors focused on compliance with satisfactory performance.
standard operating procedures (SOPs), will only reflect a ‘‘snap
In addition to the provision of equipment from the developed
shot’’ appraisal rather than providing continuous training and
countries, a resolute effort should be made to provide ‘‘hands-on’’
improvement of day to day activities [2].
training to maintain a quality system [2]. Over the past few years,
The recent drive towards accreditation of laboratories in
the Division of Microbiology and Infectious Disease (DMID) of the
developing countries by the World Health Organization Regional
National Institutes of Health (NIH) in the United States has been
Office for Africa (WHO-AFRO) [3] is a historic step to strengthen
PLoS ONE | www.plosone.org 1 June 2012 | Volume 7 | Issue 6 | e39098
GCLP Improved PT Performance
working toward improving the performance of clinical research ensure that equipment is installed properly, operates as intended
laboratories of institutions conducting NIH-sponsored clinical by the manufacturer, and continues to be suitable for its intended
trials to ensure that results generated from studies will be reliable use. The procedures carried out IQ, OQ, and PQ included inter-
and acceptable to regulatory bodies. The ultimate goal of the equipment comparison, linearity, reproducibility & repeatability
Quality Assurance/Quality Control (QA/QC) activities described (R&R) and stability of control materials. Standard operating
in this paper is to achieve compliance with the College of procedures for using and maintaining the equipment were
American Pathologists (CAP) and WHO-AFRO checklists in prepared using information in the user manuals. Users were given
preparation for accreditation through the implementation of adequate training on operation and user maintenance. A full-time
GCLP and the improvement of PT performance. biomedical engineer was employed for servicing the equipment.
In PT or External Quality Assessment (EQA), samples are sent Levy-Jennings charts were reviewed to determine the proper
out periodically to registered laboratories to be analyzed and/or frequency of calibration intervals. To ensure reagents used for our
identified. Results from each laboratory are compared with those analysis were properly stored, surprise visits were paid to the
of the other participating laboratories in the group [4,5] for suppliers and the importance of storing reagents at the required
quantitative results like creatinine concentration, or with a pre- temperatures was explained to them.
determined correct response for qualitative answers such as blood Clerical errors. We designed a process to verify clerical
parasite identification. Among other benefits, PT enhances patient entries prior to final approval of PT results. The results were
care and safety through improved laboratory practice, helps in transcribed from instrument print outs to the PT answer sheet by
identifying clinical laboratories that are at risk of performing one of the laboratory staff. Then a second laboratory staff will
poorly, and satisfies accreditation and regulatory requirements [5]. record the results from the answer sheet to the CAP website.
Individual laboratories can use PT as an aid to a continual Subsequently, the unit head or designee reviewed the entered
improvement process, by analyzing any substandard results and results against the instrument print-outs.
instituting corrective actions. Laboratory staff were advised to (1) select appropriate reagents,
The laboratories of the Noguchi Memorial Institute for Medical instrument and method codes; and to modify them if change of
Research (NMIMR), Navrongo Health Research Center (NHRC) reagent, instrument or method occurred before the next PT
and Kintampo Health Research Center (KHRC) (all in Ghana) shipment, (2) select the correct unit of measurement for each result
and the Center National de Recherche et de Formation sur le entered, (3) select the correct code if the laboratory is not able to
Paludisme (CNRFP) in Burkina Faso have been collaborating with perform testing due to instrument malfunction or reagents
the DMID in epidemiological studies and/or vaccine trials. These shortage, and (4) ask for extension in rare occasions when the
laboratories have been registered with the CAP for hematology, laboratory is not able to meet the deadline.
clinical chemistry and blood parasite surveys as a step towards Technical errors. A one-week refresher training on prepa-
continual improvement and accreditation. However, the labora- ration of quality blood smears and identification of blood parasites
tories had difficulties in consistently obtaining satisfactory scores at was organized for all of our centers at the Malaria Diagnostic
the beginning. Our aim was to identify the causes of unsatisfactory Center, KHRC in Ghana. The malaria diagnostic center of
scores in the CAP PT surveys and to put in place measures to KHRC was established as a center of excellence in 2008 as
address these causes to improve performance in subsequent collaboration between KHRC, the Walter Reed project (Kenya)
surveys. and the Malaria Clinical Trials Alliance (MCTA). KHRC
conducted this training for the other centers before the first
Methods survey for blood parasites was received in 2010. During the
A QA/QC advisor was hired in September 2009 by the U.S training, microscopists shared their SOPs and discussed many
Naval Medical Research Unit No. 3 to coordinate the activities of issues related to malaria microscopy, such as QA/QC in the
all four trial centers. All PT results obtained in 2009 by the trial collection and preparation of blood smears, parasite identification
centers for General Chemistry, Hematology and Blood Parasites and quantification. Pre- and post- test performances for each
were reviewed, retrospectively. A standardized form was distrib- microscopist were evaluated.
uted to assist the centers with the investigational process (Table 1) The need to follow specimen handling instructions that come
[6]. PT failures were classified into five main categories: clerical, with the PT kit, use of calibrated pipettes and high purity water in
methodological, technical, PT materials stability, and random preparation of chemistry reagents, calibrators and control
errors, according to criteria published by the CAP (Table 2) [6]. materials was discussed with laboratory staff. For quantitative
The contributing causes of unsatisfactory results in 2009 and 2010 tests, we monitored the standard deviation index (SDI) from the
are compared with CAP overall PT Surveys of discordant results PT summary and Participants’ Summary in relation to our test
[6]. results. We aimed at having the SDI as close as possible to zero
and our QC results as close as possible to the mean. If both SDI
QA/QC Activities and QC results indicate high or low results then calibration or
In order to improve the PT performance for the calendar year adjusting the calibration factor can resolve the issue. A high QC/
2010, the following GCLP and quality systems measures were SDI result means a QC value above +1SD and all five PT samples
taken: yielding positive SDI. A negative QC/SDI means a QC value
Methodological errors. We consulted users of various below -1SD and all five PT samples yielding a negative SDI.
chemistry equipments in our countries and evaluated their However, if there was a positive SDI with a low QC results, the
performance in PT schemes, ease of use and maintenance prior biomedical engineer and supplier were consulted, and they
to the purchase of new equipment. Uninterruptible Power Supply performed careful investigation. With the blood parasites PT, we
(UPS) systems were installed for all equipment to ensure stable redistributed misidentified slides or photographs to the micro-
power during operation. Subsequently, installation qualification socopists after grading of the challenge to allow them to have a
(IQ), operator qualification (OQ) and performance qualification second look. The participants’ summary discussion was used as an
(PQ) were performed. The equipment qualification processes in-service training aid.
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GCLP Improved PT Performance
Table 1. PT investigation aid.
Checklist of items for possible review
1 - Instrument printouts/sheet agrees with submitted information?
2 - Correct unit of measurement and decimal point?
3 - Correct user group/method listed on submitted information/report?
4 - Previous PT results show similar problem/shifts/trends?
5 - QC result for 1 month before and after PT event show evidence of problems/shifts/trends?
6 - QC record show changes of reagents, lot numbers or controls around the time of the survey?
7 - Reagent and controls within expiration date?
8 - Any other failures in this set?
9 - Any training needs identified during discussion?
10 - PT materials were retested and found to be accepted?
11 - Consultation with manufacture indicates matrix effect on the samples?
12 - Tech. re-read SOP (test method + Q.C procedure + reagent Handling) to confirm test method validity?
13 - Follow maintenance table?
14 - Last linearity of device was accepted?
15 - PT materials investigation (handling, storage, analysis sequence, re-constitution and matrix effect)?
doi:10.1371/journal.pone.0039098.t001
Extensive reviews of the user manuals for our equipment were PT stability. Our laboratories communicated with the
performed. In addition, SOPs for the maintenance and daily airport officials the importance of keeping our samples at
operation of the equipment were written and made available to all acceptable temperature during the paperwork clearance process.
personnel. Moreover, if a shipment did not arrive within five days of the
scheduled shipping date, a follow up process would be initiated.
Table 2. Classification of errors.
Error Cause(s)
Clerical 1 - Erroneous transcription of results from an instrument print-out or manual log
2 - Reporting an incorrect unit of Measurement
3 - Reporting of an incorrect method or instrument
4 - Misplacement of a decimal point
5 - The selection of an incorrect reporting code
Methodological 1 - Inappropriate use of QC materials
2 - Using QC limits that are too wide
3 - SOP lack guidance on frequency of calibration
4 - Instrument used without performing test method validation
5 - Reagent problems
6 - Poorly written SOPs
7 - Procedure not in accordance with current standard of practice
8 - Lot-to-lot variation
9 - Inadequate maintenance
Technical 1 - Inappropriate sample handling
2 - Failure to calibrate pipettes
3 - Inappropriate dilution
4 - Water quality issues
5 - Improper reconstitution, preparation or mixing of PT materials
6 - Microscopic misinterpretation
Stability of PT 1 - Improper storage conditions and/or delay in receiving
Random 1 - Any error that does not fall into any of the above categories
doi:10.1371/journal.pone.0039098.t002
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GCLP Improved PT Performance
Usually, the PT vendor provided our laboratories with a tracking Table 3. PT error rates in 2009–2010 for all centers.
number to locate the shipment during transit. Once the shipment
arrived, it would be analyzed as soon as possible.
Random errors. When all the aforementioned causes of PT
errors were excluded, we would classify the cause of failure as Year Methodological Technical Clerical Stability Random
random error, especially when repeat testing indicated an
2009 73% (131) 4% (8) 17% (31) 0 6% (10)
acceptable performance. Our laboratories would not perform
2010 72% (115) 4% (6) 6% (10) 16% (25) 2% (3)
any corrective actions when random error was identified.
Adjusting the testing system due to random errors can lead to 2009/2010 73% (246) 4% (14) 12% (41) 7% (25) 4% (13)
average
future failures.
CAP (2007) 12% 24% 51% 7% 6%
Results doi:10.1371/journal.pone.0039098.t003
Methodological errors accounted for the majority of unsatisfac-
tory results for both years in our laboratories (Figure 1). There was
performance. There was no data for KHRC in 2009 because
a 33% increase in PT conducted by the four centers (24 in 2009,
testing began 2010.
32 in 2010), and therefore more opportunities for error. However,
Figure 4 shows the average correct identification of malaria
despite the increase in testing, there was a 12% decrease in the
parasites, other blood parasites, and negative slides for all sites.
absolute number of errors, from 180 in 2009 to 159 in 2010, and
Both malaria parasites and the other blood parasites improved
the error rate per survey decreased by 35%. The greatest
significantly between 2009 and 2010 (57% to 83% and 56% to
reduction in the number errors was for clerical errors, from 31
86% respectively). All negative slides were identified correctly in
errors in 2009 to 10 errors in 2010, while methodological errors
both years.
decreased from 131 to 115 (Table 3). Most of the methodological
Our surprise visits to reagent suppliers revealed poor storage
errors were from quantitative test results. The majority of
conditions. Of the four suppliers visited, only one had temperature
quantitative errors occurs due to inappropriate or lack of
records. The recorded temperatures for the refrigerators were
calibration. However, while there was no error due to PT stability
higher than the recommended 2–8uC due to overloading of the
in 2009, this increased to 16% (n = 25) in 2010 (Table 3). Overall,
refrigerators. Room temperatures were higher than the recom-
the error rate per survey dropped from 7.5 error/survey (180/24) mended 20–25uC, as there was no air-conditioning in the reagent
in 2009 to 4.9 errors/survey (159/32) in 2010, a 35% reduction. storage rooms.
PT survey success rate in 2009 was 58% (14 of 24 PT
shipments) while in 2010 the rate increased to 88% (28 of 32 PT
Discussion
shipments) (Table 4). Average performance scores for all centers in
2009 and 2010 (Figure 2) were 77% and 90%, respectively (CAP Investigating causes of unsatisfactory performance and the
cutoff for satisfactory results is 80%). Site-specific average immediate application of interventions are crucial steps in
performances are shown in Figure 2. preventing future occurrences. Methodological errors were the
Figure 3 shows how each site performed in the different areas of major cause of unsatisfactory results in our laboratories. A
testing in 2009 and 2010. Apart from the chemistry PT for previous report from the CAP PT participating laboratories
NHRC, all other centers recorded an average score of more than indicate the possible causes of errors were 51% clerical, 24%
80% in the 2010 PTs, an improvement over the previous year’s technical, 12% methodological, 7% problem with PT materials,
Figure 1. Comparison of proportion of errors due to each type of error for unsatisfactory results at study centers in 2009, 2010, and
US averages according to CAP data.
doi:10.1371/journal.pone.0039098.g001
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GCLP Improved PT Performance
Figure 2. Average PT performance by site.
doi:10.1371/journal.pone.0039098.g002
and 6% random errors [6]. These types of errors were Test Method Validation
predominantly made in laboratories in the US, with much more Once equipment is purchased, laboratories should ensure test
experience in quality measures, and varied significantly from what method validation (TMV) is performed. TMV includes accuracy,
we found. In our centers in sub-Saharan Africa, methodological precision, analytical sensitivity, analytical specificity, reportable
errors, and not clerical errors, accounted for the vast majority of range, and reference intervals [9]. Unfortunately, in our setting,
errors. We suspect this reflects the lack of experience of many the role of suppliers has been limited to the installation and basic
laboratory staff in developing countries with quality control user training. This is similar to what was reported by Crucitti and
methods used in developed countries. Through ongoing training colleagues (2010) [2]. It is, however, the responsibility of each
and evaluation of performance on PT testing, we were able to laboratory to ensure the completion and acceptance of TMV prior
decrease the number of methodological errors per PT from 5.5 to the initiation of patient testing [10].
errors/PT in 2009 to 3.6 errors/PT in 2010, a 35% reduction in
methodological errors. Equipment Maintenance
Specific items that were noted to contribute to failures include Once equipment is installed, laboratories should ensure proper
equipment selection, test method validation, equipment mainte- scheduling, performance and documentation of daily, weekly,
nance, reagent quality and storage, quality control procedures, monthly, and other recommended maintenance [9]. Integrating
continuing education, availability of expertise, and PT stability. the user’s manual into the SOP has simplified the steps needed to
Each of these items is discussed below: accomplish assigned tasks consistently. The presence of the full-
time biomedical engineer ensures proper performance and
Equipment Selection monitoring of required maintenance which lessen equipment
Equipment related problems contributed greatly to the meth- downtime. Furthermore, due to fluctuations in the supply of
odological errors. Proper selection and acquisition of the right electricity an un-interruptible power supply system was always
equipment is the first step for a successful journey to quality [7]. provided.
We often face the dilemma of purchasing open-system equipment
which requires highly skilled staff versus closed system equipment Reagents
which often places the laboratory at the mercy of an unreliable Poor storage and transport of reagents, controls and calibration
vender to provide reagents on time. According to Petti et al (2006), materials by suppliers often leads to poor reagent performance
only 26% of laboratory staff in Ghana are professionally qualified that negatively impact the quality of testing. To eliminate these
[8]. Against this background, we performed extensive user manual effects, our trial centers now procure reagents from reputable
review, technical, and refresher trainings. suppliers who showed proper storage condition and documenta-
tion. It is important that laboratories work with suppliers in
improving service performance [11].
Table 4. PT Performance in 2009–2010 for all centers.
Quality Control
QC must be tested and acceptable results obtained prior to
Year PT success rate Average PT score release of patients results [9,12]. All centers were trained in QC
2009 58% (14 out of 24 surveys) 77% monitoring, real-time plotting of Levy Jennings charts and the
implementation of statistical QC rules [13]. Laboratory supervi-
2010 88% (28 out of 32 surveys) 90%
sors were trained on how to calculate and implement in-house
doi:10.1371/journal.pone.0039098.t004 control values as ranges provided by manufacturers tend to be too
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GCLP Improved PT Performance
Figure 3. Performance by Center for 2009 and 2010 for blood parasites, chemistry and hematology.
doi:10.1371/journal.pone.0039098.g003
wide [9]. The adaptation of in-house tighter control ranges assisted assist our centers to overcome ‘‘intellectual isolation’’ [15].
our centers in the early detection of accuracy and precision related Improving accuracy of malaria microscopy can avert the recent
problems before it affects participants’ results and/or PT samples. trend of Ghanaian physicians who use empirical methods to
diagnose malaria [16].
Continuing Education
Some of the errors encountered in the blood parasites surveys QA/QC Expertise
came from non-malaria organisms such as Babesia, Leishmania, and The presence of a QA/QC advisor provided the centers with
microfilaria (pre-larval stage) which are not commonly seen in our the hands-on technical support needed during clinical trials. Most
centers. The malaria microscopy refresher training provided of the supervisors in resource limited settings lack the technical
laboratory microscopists from all centers an opportunity for expertise necessary to ensure accuracy of test results [8]. It is
interaction and experience sharing. Networking and exchange of obvious that establishing a quality assurance program will increase
information among scientists in resource limited settings is vital the trial budget [2]. However, these activities will ensure the safety
[14]. Scheduling regular refresher training among scientists will of participants, accuracy of testing and subsequently improve
Figure 4. Average correct identification of the blood parasites surveys for all sites.
doi:10.1371/journal.pone.0039098.g004
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GCLP Improved PT Performance
healthcare in resource limited settings [2]. According to Simon 2009. KHRC did not have scores for 2009 because participation
[17], programs measure their success by factors such as: the in the PT surveys started in 2010.
number of publications, work cited, number of funded studies, and Improving the performance of laboratories in PT is a
number of scientist trained. Sustaining successful performance in continuous process. Through a continuous program of education
proficiency testing should be used as a direct indicator of the and training described above, we were able to achieve a 35%
quality of laboratory performance. reduction in errors over the course of a year. However, despite a
35% reduction in methodological errors, this type of error remains
PT Stability the most common cause of errors at the four clinical trial centers in
We did not experience unsatisfactory performance as a result of sub-Saharan Africa, accounting for 73% of errors. Comparing this
unsuitable PT samples in 2009. This was, however, a significant rate to the US rate of methodological errors of 12%, emphasizes
contributing factor to the errors encountered in 2010. The PT the need for more training of laboratory staff in this region in
stability error rate was about two times the value of the CAP data. quality control methods that are well established in developed
Issues with PT survey materials stability are common in countries. Our centers will continue to use PT to improve Quality
Assurance practices in our laboratories. We look forward to a
international laboratories. Many times the PT materials travel
continuous improvement process and sharing our experiences with
through several airports and warehouses before they arrive at their
other laboratories in the region.
final destination. The temperature during the travel is not
monitored and/or controlled. Some of the PT materials will
require customs clearance before or after its arrival. Ensuring Acknowledgments
proper storage conditions during the paperwork processing is Authors’ Disclaimer Statement
crucial to the stability of the PT materials. Some postal carriers, The views expressed in this article are those of the author and do not
who lack refrigeration facilities at the airport, can accept necessarily reflect the official policy or position of the Department of the
refrigerators donated by laboratories to be used for storage of Navy, Department of Defense, nor the U.S. Government.
Copyright assignment statement
their shipment. However, this step will require a complete
I am a military service member (or employee of the U.S. Government).
understanding from the postal carriers of the importance of This work was prepared as part of my official duties. Title 17 U.S.C. 1105
compliance with temperature requirements. Laboratories should provides that ‘Copyright protection under this title is not available for any
monitor the shipping calendar closely. Any delays of samples work of the United States Government.’ Title 17 U.S.C. 1101 defines a
testing can negatively impact the quality of results. International U.S. Government work as a work prepared by a military service member
laboratories do not have to order the PT product with less than ten or employee of the U.S. Government as part of that person’s official duties.
days of stability [18]. The PT ordering booklet contains the list of
tests with less than ten days shelf life. An alternative assessment Author Contributions
should be performed instead [19]. Conceived and designed the experiments: FI DD KCK IO TA HA SS
SOA KK. Performed the experiments: FI DD IO TA HA. Analyzed the
Conclusion data: KCK SS SOA KK. Contributed reagents/materials/analysis tools:
FI DD KCK IO TA HA SS SOA KK. Wrote the paper: FI DD. Obtained
The intervention impact has been positive. All our centers had a
and submitted data: FI DD IO TA HA. Reviewed data, manuscript, and
higher average performance score in 2010 compared to that of provided guidance: KCK SS SOA KK.
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