2019, Volume 35, Number 3, Page(s) 228-236
Lean Methodology for Pathology Laboratories: A Case Study from a Public Hospital
Fatih DURUR, Yasemin AKBULUT
Department of Healthcare Management, Ankara University, Faculty of Health Sciences ANKARA, TURKEY
Keywords: Cost, Efficiency, Lean methodology, Management, Pathology laboratories, Waste
Objective: The increase in the financial imposition of laboratories together with developing technology and evidence-based medicine applications increased the importance of quality and efficiency studies in laboratories. The aim of the study is to examine the processes of pathology laboratory, determine the causes of waste and select lean management techniques to eliminate the causes of waste.
Material and Method: A five-phase plan was used for the application of lean management in the pathology laboratory. After a comprehensive literature review, these phases were determined as follows; the support of the senior management, observation, training of employees, drawing of value stream maps and creation of value stream plan. Gastric biopsy process was selected as product/service family when value stream maps were generated. In addition, fishbone diagram and Pareto analysis were used to determine the causes of waste.
Results: In the current state, 73.6% of the time spent on a gastric biopsy sample in the pathology laboratory was wasted. The most common causes of waste were identified as problems with cleaning, equipment supply problems, lack of clinical information, equipment malfunction and errors. A value stream plan was developed with lean techniques to eliminate the causes of these wastes. In the pathology laboratory, a 4.6% improvement will be achieved with the achievement of the future stated target.
Conclusion: A model for lean management techniques in a developing country that will enable the pathology laboratories to work more efficiently and with improved quality has been developed in this study
Lean management is a method recommended for reducing
waiting times, waste and costs in health care facilities to
improve quality and efficiency 1,2
. In an environment
where health expenditures are constantly increasing and
resources are limited, health institutions should reduce
their costs and increase their efficiency in order to survive.
In recent years, in order to reduce waste, improve processes
and increase efficiency, the number of health institutions
applying lean management has increased. In this way, they
aim not only to compete with other institutions but also to
increase and stabilize their market share 3-5
Although lean management studies in the public health
sector are more disadvantaged than the private sector in
terms of budget, hierarchical structure and sustainability,
successful results can be obtained 6-8. Lean management
in the public sector is used to improve clinical processes,
patient care, treatment practices, operation and laboratory
processes, and imaging services 9-17. However, since
laboratories are the units that are most similar to a processing department within health care institutions, they
are widely accepted in lean management practices and are
generally chosen as the starting point in lean management
practice 3,5. In addition, advances in diagnosis and
treatment, evidence-based medicine practices and
technological changes, as well as the increased financial
restrictions imposed on laboratories, have increased the
interest in quality and productivity in laboratories 18,19.
On the other hand, the number of lean management
studies conducted in pathology laboratories is very limited
and generally include examples from developed countries
This study was carried out in the pathology laboratory
of a public hospital in Ankara, Turkey. The aim of the
study is to examine the processes of pathology laboratory,
determine the causes of waste and select lean management
techniques to eliminate the causes of waste. With this
leading work, a model is proposed in lean management
techniques in a developing country that will enable the
pathology laboratories to work more efficiently and with
This study was carried out at Diskapi Yildirim Beyazit
Training and Research Hospital with 770 bed capacity in
Ankara, Turkey. The hospital with 770 bed capacity, 68
intensive care beds, 29 operating rooms, intensive care
services, pathology, microbiology, biochemistry, genetics
and tissue typing laboratories and emergency services
with a total of 174 main branches and sub-branch clinics.
In hospital pathology laboratory, histopathology and
cytopathology services are provided. Immunohistochemical
staining and histochemical staining can also be performed.
There were 43 employees in the pathology laboratory at
the time of the study. The laboratory, which has more than
30000 materials a year, serves 5 days a week between 08.00-
17.00 hours 25
This study was carried out between September 2017 and
May 2018. Data on this current state of the pathology
laboratory were obtained from the hospital statistical
unit and pathology laboratory. In addition, participatory
observation and unstructured interview method were
used to collect the data of lean methodology and semistructured
observation forms were used to record the
findings obtained during the observation.
Lean management is based on five basic principles: value,
value stream, flow, pull and perfection 1. Application
phases and techniques used differ according to the work
spaces. As a result of literature review in this study
1,2,3,5,11,26,27 an application plan consisting of five
phases was created. These phases were determined as
taking the support of the senior management, observation,
training of the employees, drawing up the value stream
mapping and creating the value stream plan.
Phase 1: Support of the Senior Management
Senior management support for lean management practices
is the first and the most important element 1,3,28. The
most important factor in the selection of the hospital is
that the hospital staff members had been trained in lean
management in health institutions. As a result of face-toface
meetings with senior management, the management
participation for the study conducted was guaranteed. They
were eager for lean practices and provided legal permission
for the study.
Phase 2: Observation
In the second stage of the study, one month (November
2017) with intermittent observation method 14
observations were performed in the pathology laboratory.
During observations, semi-structured observation forms
were utilized to record the data to be used in other stages of
the study. In order to strengthen the observation method, it
is recommended to use together with the interview method
29,30. For this reason, information about pathology
laboratory processes was obtained from the employees
with unstructured interview method.
Phase 3: Training of Employees
As employee participation is very important in lean
management applications 31,32, employees are required
to know the lean management terms and the lean
management tools. For this purpose, training programs
covering lean management concepts and definitions,
techniques used in lean management practices and
examples of lean management in health institutions were
organized. The training programs were carried out by
researchers in two sessions of 50 minutes to physicians and
other laboratory staff. At the same time, the employees and
researchers exchanged ideas for the next stages of the study
and their questions were answered.
Phase 4: Value Stream Mapping
It is aimed to visualize the process steps with value stream
mapping, to determine the causes of waste in the process
and to create plans for the elimination of these matters 33.
In this way, process spaces that work in accordance with
lean management principles can be revealed. The product/
service family selection, creating the current state map and
setting the future state map were followed in the creation
of the value stream mapping in the pathology laboratory in
this study 15.
Product/Service Family Selection
It will be quite complicated to show the entire process
and stream of information in a business area on a single
map 33. For this reason, firstly a product/service family
selection should be made in value stream mapping. In this
study, gastric biopsy samples were selected as product/
service family considering the number of samples and units
in which they were processed in the laboratory. In this way,
it was possible to examine all processes in the pathology
Current State Map
The next step after selecting the product/service family
is the creation of the current state map. The data used in
the preparation of the current state map were obtained
from the records of the pathology laboratory as well as
observations and interviews. For the calculation of the
periods with added value and waiting time (did not add
value), the samples were monitored during the process
and measurements were made with the timepiece. In this
study, gastric biopsy samples consisting of 44 models
were selected and recorded as product/service family for
recording the current state map.
In this current state, there are 11 pathologist, 7 assistant
pathologist, 15 laboratory technicians, 7 medical secretaries,
2 servants and 1 hospital cleaning staff in the pathology
laboratory. The laboratory serves every weekday between
08.00-17.00 hours. During this period when the study was
carried out, a total of 25488 samples, 20274 biopsies and
5214 cytology were examined in the pathology laboratory.
The results in the biopsy period in the pathology laboratory
were 3.99 working days; the period of cytology results was
2.57 working days. When the number of inappropriate samples was examined in the pathology laboratory; it was
observed that 90 samples were rejected between January,
2017 and May, 2018. When the reasons for rejection were
examined, pre-diagnosis/clinical information deficiency
(n=25), inappropriate transfer (n=17), lack of doctors
cachet (n=15), irregular entry (n=10) and other reasons
(n=23) were determined.
The basic processes in pathology laboratory value
stream include pathology request, sample acceptance,
macroscopy, tissue surveillance, blocking, sectioning,
incubator, staining/coverslipping, immunohistochemistry/
histochemistry, microscopic examination, reporting, report
control and archive steps. In the pathology laboratory, it
was observed that there is a long waiting period between
the stages of macroscopy/tissue surveillance, microscopic
examination/reporting and report control/conclusion. In
the pathology laboratory, the current state mapping for the
gastric biopsy (Figure 1) was examined, time of stream in
the pathology laboratory was 74 hours 09 minutes, waiting
period was 54 hours 37 minutes, and a value added period
was 19 hours 32 minutes. Currently, 73.6% of the time spent
in the pathology laboratory for gastric biopsy samples did
not add value.
In the pathology laboratory, the wastage reasons determined
by the current state mapping are listed below:
It has been determined that appropriate transport
containers were not used for transfer of pathology
samples to the laboratory. For transfer of samples to
the laboratory, carrying cases that hold materials at a
certain temperature should be used. Samples which are
not carried under appropriate conditions may affect the
pathology result. In addition, rejection of samples that
were not carried under appropriate conditions causes a
waste of time and cost.
Lack of clinical information sent in request forms
causes waste of time. The lack of clinical information
was among the top reasons for sample rejection.
The lack of clinical information affects pathologists
diagnosis times and causes wasted time and error.
There was no warning system for infected material
(HIV, Hepatitis) on samples sent to the pathology
laboratory. This can be a waste of error and also pose a
threat to occupational safety.
Samples taken to the sample acceptance and recording
unit were both electronically recorded to the hospital
information management system (HIMS) and a
pathology registry was kept manually. Post-recording
samples were very difficult to follow in laboratory. This
situation causes waste of time and error. In addition,
the tracking number of the materials coming to the
laboratory was given manually by the secretary. This
may cause possible waste of error.
During the report creation phase, a secretary at the
macroscopy unit wrote a report to the assistant or
senior physician. This causes waste of error and time.
Laboratory unit is the area where blocking, sectioning,
incubator and staining/cover slipping operations are
performed. In the pathology laboratory there was
an employee responsible for cleaning and supply of
materials. Lack of these personnel in this area causes
problems in cleaning and supplying materials.
In the laboratory, the outcome report was recorded by
the secretary after being registered to HIMS, and two
outputs (for patient and archive) were submitted to
the approval of the pathologist. If the report required
correction, the process was repeated. This causes
unnecessary material use and unnecessary act of the
secretary. In addition, the time elapses and there is
dissipation of time.
In the laboratory, there was no archiving area for the
samples coming with consultation. This can cause
possible waste of error, making it difficult to find
materials and also wastes time.
Future State Map
The next step after the current state map was the creation
of a future state map. The transportation of the samples
to the laboratory with the future state map, sample
acceptance, macroscopy, reporting and archive sections
were determined as kaizen point. In addition, the sample
acceptance unit was selected for 5S application in the
laboratory area including work standardization and
blocking, sectioning, incubator, staining and cover slipping
(Figure 2). Although some processes in the pathology
laboratory did not create value, they must be maintained
in the current state. For example, samples wait for 13
hours 03 minutes for tissue surveillance after macroscopy
and this causes time wasting. However, an improvement
to eliminate this waste will result in the accumulation of
staining and microscopic examination units. Therefore, in
order to maintain the current state, this waiting is currently
required and cannot be eliminated.
In the preanalytical process with future state map, it is
aimed to eliminate error and time with kaizen applications
in macroscopy units and sample acceptance; waste and
unnecessary movement wastes with the 5S application
to be made in the laboratory area. With kaizen practices
after the reporting at the report control phase the time,
cost and movement wastage will be prevented. In addition,
continuous stream can be achieved with the principle of
pulling between the report and the report control, thus
eliminating the waiting period of 11 hours. In this case,
the stream time will be 63 hours 09 minutes, the waiting
time will be 43 hours 37 minutes, and the value added
time will be 19 hours 32 minutes. The rate of waiting time
will be reduced from 73.6% to 69% and there will be an
improvement of 4.6%.
Phase 5: Value Stream Plan
A value stream plan was prepared in order to achieve the
goals set in the future state map. In this study, the fishbone
diagram and Pareto analysis were used to develop lean
managements principle of respect for people and 3<,r34>
and to increase employee participation in the value stream
plan. The causes of wastage as a result of the value stream
mapping, observations and meetings were visualized by
the fishbone diagram as a result of brain storming with
employees of pathology laboratory (Figure 3).
Causes of wastage as a result of fishbone diagram were
determined as unnecessary procedures, lack of information
system, equipment malfunctions, equipment supply
problems, errors, lack of clinical information, cleaning
problems and transportation problems. These causes of
waste in the pathology laboratory were collected under the
headings of method, equipment, people and other causes.
After the creation of the fishbone diagram, Pareto analysis
was carried out to select the most important reasons. A form determined by the fishbone diagram was created
for the Pareto analysis, and the employees working at the
pathology laboratory were asked how often these kinds of
waste were encountered. In order to make the necessary
calculations for Pareto analysis, the results were rated
as rarely = 1, sometimes = 2, generally = 3, and frequent
= 4. Thirty-five of the pathology laboratory employees
volunteered to participate in the study. In the first stage,
the data were classified, and the cumulative points and percentages were calculated. Cleaning problems were
the most common waste with 88 points; the problems
encountered in transportation were determined as the least
commonly encountered waste with 51 points. A Pareto
analysis chart was created to visualize the cumulative scores
and percentages calculated in the second stage to apply the
20/80 rule 35 and to determine the causes of waste to be
given priority (Figure 4).
As a result of Pareto analysis, problems which were below
80% were selected. These were problems that related to
cleaning, problems in supplying material, lack of clinical
information, machine failures and errors and thus
determined as priority headings. Unnecessary procedures,
lack of information systems and problems in transportation
Wastage points determined by the fishbone diagram and
value stream maps were prioritized by Pareto analysis. After
this stage, a value stream plan was established in order to
reach the targets in the future state map. The value stream
consisted of the determined causes of waste, waste types,
the lean techniques to be used and solution offers (Table I).
In the study, value stream maps, current state of
the pathology laboratory and wastage reasons were
determined. Accordingly, the duration of stream in the
pathology laboratory for a sample of gastric biopsy was
determined as 74 hours 09 minutes; waiting period was 54
hours 37 minutes and value added duration was 19 hours
32 minutes. In the current state, 73.6% of the time spent in the pathology laboratory for gastric biopsy samples
has no added value. With the future status map and value
stream plan, it was calculated that the stream, material
and unnecessary movement wastes could be eliminated,
thus, the stream time could be reduced to 63 minutes 09
minutes, waiting period is 43 hours 37 minutes and value
added duration is 19 hours 32 minutes. In this case, the rate
of duration that does not create added value will be reduced
from 73.6% to 69% and there will be an improvement as of
4.6%. In order to reach the targets, set in the future status
map and to increase employee participation, a value stream
plan was created by using fishbone and Pareto analysis.
The value stream plan and the wastage reasons defined
in the pathology laboratory were classified as wastes of
time, error, movement and material and were arranged
according to the result of Pareto analysis. Kaizen, business
standardization, 5S and visual management were chosen
from lean management techniques and solutions were
proposed to eliminate the causes of waste.
In this study, the steps of lean management practices
performed in a public hospital pathology laboratory are
presented. A process analysis based on a lean methodology
was performed for the first time in a public hospital
pathology laboratory in Turkey. At the end of the study,
it was calculated that the waiting period which was 54
hours 37 minutes can be reduced to 43 hours 37 minutes
and an improvement of 4.6% can be achieved. In this way,
the number of samples examined can be increased. These
results are supported when the literature is reviewed. As a result of the lean application of the histopathology
department of an anatomical pathology laboratory, the
total cycle time decreased from 9.7 hours to 9 hours and the
number of samples examined increased from 3439 to 4074
. Another study conducted in the pathology laboratory
found that, the total time spent by the sample in the system
has been reduced from 507 minutes to 238 minutes, while
the process that did not add value has been reduced from
358 minutes to 89 minutes 23
. In the study carried out
in South Dokota, the total cycle time was reduced by 67%
and the number of samples examined increased 37
a result of the study conducted in a pathology laboratory
in an oncology hospital in Brazil, the reporting time were
. In another study conducted in Canada, the
rate of autopsy reports given within 90 days was increased
from 37% to 74% 39
. In addition, the total cycle times
and the increase in the number of examined samples were
found in the studies conducted in the central laboratories
of different hospitals 11,19,36
Also it was determined in this study that the value stream
plan, error and movement wastes in the pathology
laboratory can be eliminated. In the pathology laboratory
of Dokuz Eylul University Hospital, a study was performed
by using various lean instruments to increase productivity.
As a result of the study, the total number of errors were
reduced from 110 to 64 and the number of mislabeling
errors were reduced from 30 to 15 24. In the study
conducted in a pathology laboratory of a hospital in
Detroit, the error rate was reduced by 55% 20. Another
study conducted in Australia eliminated 187 kilometers
unnecessary walking per year 22. In the pathology
laboratory of the University of Michigan Hospital, the lean
applications performed during the Pap test process resulted
in an approximately 50% reduction in the number of errors
while in another study conducted in the USA, near-miss
events (events, actions or processes expected to be severely
damaged if not corrected before reaching the patient) were
reduced and contributed to patient safety 40,41. Business
processes have been redesigned with lean management
applications made in a pathology laboratory in Cleveland
and unnecessary movement and time wastes have been
In conclusion, lean management philosophy takes a long
time to adopt. Presenting the results of the first phase of a
large project is the limitation of the study. The effects of the
results obtained with the application of the lean techniques
determined in the value stream plan as a result of the study
on the costs, results waiting time and error rates can be examined in other studies. In addition, the methodology
developed to carry out the study can be an example to
lean management studies in medical laboratories. In it
is important to note that in order to achieve success in
lean methodology, the key elements are: the continuous
training of employees and their participation in the process.
Furthermore, the introduction of the application primarily
in a part of the laboratory and then disseminating it to the
pre-analytical and post-analytic processes can lead to the
creation of a lean management culture.
This study was supported by the Ankara University
Scientific Research Projects Coordinatorship.
The authors thank İlhan AYDIN, M.D. and all pathology
department staff for their contributions.
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