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Andrea R
Horvath1*, Joseph Watine2*, Tivadar L
Miko3
1Department of Clinical Chemistry,
University of Szeged, POB 482, H-6701 Szeged, Hungary
2H�pital de Rodez, F-12027 Rodez Cedex 9 France
3Department of Pathology, University of Szeged, POB 427,
H-6701 Szeged, Hungary
*Committee on Evidence-Based Laboratory Medicine,
IFCC
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The relationship between quality, clinical effectiveness
and evidence-based laboratory medicine
Evidence-based healthcare (EBHC) evolves from quality
improvement initiatives and there is a significant overlap between
the approaches and methodologies of evidence-based medicine (EBM)
and quality management. The primary aims of both EBHC and quality
management of health care services are to improveclinical
effectivenessand patients'outcomes. EBM and evidence-based
laboratory medicine (EBLM) are essential tools in the assessment of
effectiveness, as high quality systematic clinical research is
necessary for investigating the impact of any intervention on
clinical outcome.
Effectiveness of service is also referred to in the new ISO
15189:2003 standard for medical laboratories (Clauses4.7, 4.15.1).
Clinical effectiveness of laboratory services refers to the best
achievable outcome of service delivery in routine circumstances. It
depends on the diagnostic performance of a test (i.e.efficacy), the
applicability of this finding to local circumstances
(i.e.efficiency or cost-effectiveness), and the standards,
organisation and management of service (i.e.quality). Burnett
defines quality as �fitness for purpose� and also relates the
evaluation of service to its ability to satisfy stated or implied
needs (1). It is very important that this broader term of quality
is used in the healthcare context. While quality assurance and
quality assessment tools usually measure whether things are done
well, EBM and EBLM challenge whether the principles of �fitness for
purpose� are met (2), and whether the laboratory responds to the
needs of its users. For example, a laboratory may measure random
glucose and blood gases on all healthy patients entering the
day-care unit for minor surgery and provide this service at high
quality (i.e. laboratory staff doing their work competently and to
high professional standards). In terms of clinical effectiveness
and �fitness for purpose�, however, this otherwise �high quality�
service is a waste of time and resources, and practice does not
follow evidence-based guidelines which recommend no testing in this
group of patients (3).
From the above it follows that quality management and
accreditation of medical laboratories are part of the clinical
effectiveness cycle (Figure 1) (4). Accreditation can achieve its
prime aim (i.e. improving the quality and effectiveness of service)
only if standards, as a �level of excellence or quality� are
defined and measured in an evidence-based manner.
Relationship between
requirements of ISO 15189:2003 and EBLM
In the following sections clauses of ISO 15189:2003 (quoted in
italics), where the principles of EBLM can be applied, will be
discussed in more detail (5).
ISO 15189:2003 4.
Management requirements
Health needs and service needs
The �needs� of customers are mentioned nine times throughout the
text of ISO 15189:2003 (Introduction, Clauses4.1.2, 4.4.1.c, 5.5.1,
5.5.2, 5.8.8, 5.8.11, B5.4, B6.1). We highlight below those clauses
that deal with this issue as a key requirement.
ISO 15189:2003,
Introduction
Medical laboratory services are essential to patient care and
therefore have to be available to meet the needs of all patients
and the clinical personnel responsible for the care of those
patients (5).
ISO 15189:2003, 4.1. Organization and management
4.1.2. Medical laboratory services, including appropriate
interpretation and advisory services, shall be designed to meet
theneeds of patients and all clinical personnel responsible for
patient care (5).
Before discussing the meaning of the term �needs�, we have to
define who the �customers� of laboratory services are. Customers
are users of laboratory services, including patients, clinical
staff and purchasers (Clause5.1.4.c). According to this, the �needs
of users� have to be interpreted from different perspectives, and a
distinction should be made betweenhealth needsof patients
andservice needsof health care staff and purchasers.
The ultimatehealth needsof patients, in terms of laboratory
services, are to provide high quality, reliable diagnostic
information which supports the correct screening, diagnosis,
differential diagnosis, monitoring, prognosis or risk assessment of
a given health condition. EBLM is instrumental in providing
reliable and valid scientific data on the diagnostic efficacy of
laboratory investigations, thus contributing to satisfying the
needs of its prime users.
Service needsrelated to medical laboratories are linked to
technical, organisational, financial or ethical considerations
which often involve a consultation process and contracting between
the laboratory and the users or buyers of its services. Service
needs can also be related to the provision of technically reliable
and accurate data (Clauses5.5, 5.6) at fast turnaround times
(Clause5.8.11), and at the lowest possible costs (Clause5.1.4.i).
The impact of these needs on outcomes has to be addressed by
suitable research and assessed in clinical audit cycles � both
areas being within the scope of EBLM.
Evidence-based
standards, criteria and indicators
ISO 15189:2003, 4.2. Quality management system
4.2.3. Policies and objectives of the quality management system
shall be defined in a quality policy statement�This policy� shall
include the � laboratory management�s statement of the laboratory�s
standards of service; �and the laboratory�s commitment to good
professional practice,� (5).
To achieve good professional practice, criteria and standards
for best practice need to be valid. Valid criteria are based on
evidence, measurable, and must respond to the needs of users (6). A
conference of the Joint Commission in 1999 collected votes from 50
countries on accreditation issues and 81% of participants concluded
that if evidence clearly supports best practice and clinical
effectiveness, accreditation standards should adopt these findings
(7).
Systematic reviews or evidence-based guideline recommendations
provide useful information when developing criteria and practice
standards (8, 9). If high quality secondary publications are not
available, systematic searching of the primary literature and
critical appraisal of the evidence are needed (9). In lack of
scientific evidence, the views and formal consensus of professional
groups should inform the process. It is very important that the
sources of information underlying standards and criteria are
explicitly stated. Evidence-based criteria and standards can be
used in several other quality management activities investigating
the clinical performance of laboratory service:
- identification and control of nonconformities (Clause4.9),
- preventive action (Clause4.11),
- continual improvement (Clause4.12),
- internal audit (Clause4.14),
- clinical audit (10) and
- management review (Clause4.15).
ISO 15189:2003,
4.12. Continual improvement
4.12.4. Laboratory management shall implementquality indicators for
systematically monitoring and evaluating the laboratory�s
contribution to patient care (5).
Measurement of current practice is based on criteria and
measurable indicators (10) that can be classified according to
whether the problem reviewed is related to structure, process or
outcome of care (e.g. improvement of morbidity, mortality, patient
satisfaction, decrease of turn-around time) (6). It is difficult to
develop evidence-based outcome criteria in laboratory medicine for
the lack of outcome studies, poor quality of primary studies,
sources of bias (e.g. lead time and disease progression bias), poor
transferability of research data due to heterogeneity of the
investigated patient and disease spectrum, etc. Therefore surrogate
outcome criteria are often used which are easier to measure (6).
For example, HbA1c measurement is a proxy outcome for diabetes
control and indirectly assesses the long-term clinical outcome of
morbidity due to secondary complications of the disease.
Prioritization
and monitoring ISO 15189:2003, 4.14. Internal audits
4.14.2.�internal audits of all elements of the system, both
managerial and technical, shall be conducted�The internal audit
shall progressively address these elements and emphasize areas
critically important to patient care (5).
The above statement emphasizes the need for prioritization of
key areas of laboratory services relevant to patient care. As
resources are limited in every laboratory, management should
identify and prioritize areas, which have the greatest impact on
effectiveness, in a systematic way. Research evidence can inform
several steps in the prioritization process. When prioritizing, the
following questions may need addressing (6, 8):
- Is the area concerned of high cost, high volume, or increased
risk to users?
- Is there a serious quality problem, patient complaints or
harm?
- Is good evidence available to support diagnostic
decisions?
- Is there potential for change and improvement?
- Is the area a national health priority?
- Is the area important for the organisation?
Critical areas shall be audited in collaboration with clinical
staff, if relevant. Multidisciplinary clinical audit, comparing
actual performance with practice standards, is a powerful tool in
setting targets for quality improvement and in bringing about
change in service delivery. The term �clinical audit� is not quoted
as such in ISO 15189:2003, however, it is referred to indirectly
both in Clause 4.14. and 4.15.
ISO 15189:2003,
4.15. Management review
4.15.1. Laboratory management shall review the laboratory�s quality
management system and all of its medical services, including
examination and advisory activities, to ensure their continuing
suitability and effectiveness in support of patient care and to
introduce any necessary changes or improvements.
4.15.3. The quality and appropriateness of the laboratory�s
contribution to patient care shall�be monitored and evaluated
objectively (5).
These sub-clauses highlight the responsibility of management in
monitoring effectiveness and the employment of quality improvement
cycles through the practice of clinical audit. It is particularly
important that the requirement emphasizes �suitability�,
�appropriateness� (whether the service is provided to the right
people, at the right time) and �quality� of service in a broad
sense. Application of research evidence helps in determining what
suitable, appropriate and high quality is, in terms of effective
diagnostic service, supporting the care of patients in the
community.
ISO 15189:2003 5.
Technical requirements
Do laboratory personnel have skills of EBLM?
ISO 15189:2003, 5.1.
Personnel
5.1.4.The laboratory director or designees for each task should
have appropriate training and background to be able to�a) provide
advice�about the choice of tests,�and interpretation of laboratory
data; �d) define, implement and monitor standards of performance
and quality improvement of the medical laboratory service�(5).
EBLM supports diagnostic and therapeutic decisions by providing
objective data for informed medical decisions. Do laboratory
personnel meet the above requirements and do they have �appropriate
training and background� for applying evidence in practice (11)? An
EC4 consultation document on the �Competence to be a consultant in
laboratory medicine� emphasizes the need for �skills to search for
and critically appraise the evidence and to apply evidence for
optimising service provision� (12). The IFCC Committee on
Evidence-Based Laboratory Medicine (C-EBLM) has recently carried
out an international survey which demonstrated in many countries
that formal training in EBLM is still lacking both at undergraduate
and postgraduate level, and most curricula for specialist training
do not cover EBLM (unpublished). In order to fill in these gaps,
and to respond to the training needs of the IFCC community, the
C-EBLM, together with experts of the Cochrane Collaboration, will
organise a 4-day postgraduate course on EBLM in September 2005 (for
details, see www.ifcc.org). The philosophy, opportunities,
tools and resources for teaching EBLM have been reviewed by Price
and Christenson recently (13). In the lack of good outcome studies,
however, it remains to be demonstrated whether skills in EBM
contribute to the improvement of the effectiveness of care (14,
15).
We mentioned above that EBLM is a decision support tool guiding
both diagnosis and therapy. Diagnostic decisions are based on
several factors. Testing depends on the prevalence and pre-test
probability of the target condition, and information about the
quality specifications (i.e. test information), and the
discriminatory power and interpretation (i.e. post-test
information) of the applied investigations. The potential role of
EBLM in these different phases of the diagnostic process (i.e.
pre-test, test and post-test phases), in relation to the relevant
chapters of ISO 15189:2003, will be discussed in the following
sections.
Evidence-based
test ordering ISO 15189:2003, 5.4. Pre-examination
procedures
5.4.1. The �manner in which requests are communicated to the
laboratory should be determined in discussion with the
users�(5).
The pre-examination phase starts with the selection of the right
test(s) for the right patient and at the right time. The fulfilment
of the above requirement is one of the most critical areas of
laboratory services, as both over- and under-utilization of
diagnostic services occur and may cause harm to patients (16). The
laboratory is responsible for giving �advice on choice of
examinations and use of the services� (Clauses4.7 and 5.1.4.a).
What should this advice be, where should it come from, and how can
we transmit this information to clinical staff? According to the
principles of EBLM, a diagnostic test should be requested only when
an appropriate question is asked and when there is evidence that
the result will provide an answer which will influence the clinical
decision (17). Therefore, EBLM and accreditation in the
pre-examination phase have the same goals, i.e. they both aim at
improving test ordering patterns. Improved laboratory test
selection combined with the enhanced presentation and
interpretation of test results are cost-effective tools in changing
requesting patterns and the use of diagnostic services by clinical
staff (18-20). Laboratory management should be aware of the fact
that changing test ordering behaviour is a difficult and endless
task, needing continuous attention (20). Strategies that have been
shown to work well include:
- changes to request forms and reduced availability of tests on
forms,
- audit and personalized feedback to clinicians,
- computer reminders
- and financial incentives or disincentives (20, 21).
Interventions that worked less well include single training
courses, lectures and CME. Feedback on costs or written materials
on test ordering showed little or no effect. Implementation of any
of these strategies needs to be tailored to local circumstances,
and it is most likely that combination of different strategies will
provide the largest impact.
Evidence-based
analytical performance goals
ISO 15189:2003, 5.5. Examination procedures
5.5.1. The laboratory shall use examination procedures�which meet
the needs of the users of laboratory services and are appropriate
for the examinations.
5.5.4.Performance specifications for each procedure used in an
examination shallrelate to the intended use of that procedure
(5).
The use and interpretation of laboratory investigations largely
depend on the suitability of the methods of analysis for the
intended application (Clause5.5.4.). Test performance in the
clinical setting is grossly influenced by the analytical quality of
methods (Clause5.6) (22) and the biological variation of the given
parameter. The latter is also essential in the determination of
analytical performance goals (23, 24; www.westgard.com/guest26.htm). The �evidence�
used to establish analytical specifications of laboratory tests
appears to be based largely on the consensus of experts, which
scores a relatively low grade on any evidence scale. Therefore it
seems appropriate to consider additional scientific approaches to
strengthen the recommendations for defining biological variability
and for setting analytical performance goals (23, 25).
Evidence-based
information on diagnostic utility of tests
ISO 15189:2003, 5.7. Post-examination procedures
According to the terms and definitions of ISO 15189:2003(E) 3.9,
post-examination procedures include �systematic review, formatting
and interpretation, authorization for release, reporting and
transmission of the results, and storage of samples of the
examinations� (5).
The aim of EBLM in the post-test phase is to assist clinicians
and patients both in the interpretation and in the clinical
utilization of laboratory results. Accreditation standards also
refer to the necessity of �interpretation of the results of
examinations� (Clauses4.7, 5.1.4.a, 5.8.3.j). How can we best
deliver information on diagnostic utility of tests to healthcare
professionals and patients?
When clinicians wish to make a diagnosis, they use tests as
modifiers of disease probabilities in order to convert pre-test
probability information to post-test probability estimate of a
certain target condition. For making this judgement it is essential
to know the diagnostic accuracy, i.e. the sensitivities and
specificities, or the likelihood ratios of tests, which enable them
to transform pre-test data into clinically meaningful information.
It is the responsibility of laboratory professionals to present
test results in clinically meaningful ways. Preliminary data
suggest that interpretative comments on laboratory reports,
provided they are written by well-trained and competent staff,
could be one of the possible answers to this problem (26).
To help physicians to utilize laboratory services efficiently,
the supporting evidence or guideline recommendations should be made
accessible at the point of clinical decisions, preferably directly
linked to patient data. Information technology can provide means to
integrate decision support into patient care (27). Several
initiatives and a number of evidence-based databases exist,
including a systematic reviews database related to laboratory
medicine recently released by the IFCC Committee on EBLM (www.ifcc.org).
Conclusions
EBLM gathers information from well-conducted research studies on
the pre-test, test and post-test performance of laboratory
investigations, and incorporates this evidence into the routine
practices of medical laboratories. EBLM is an excellent method to
enable better clinical decisions, and to integrate routine
laboratory service with effectiveness, quality management,
education and training in laboratories. By the process of constant
questioning and reviewing current practice, and comparing it to the
best available evidence for rational diagnosis and therapy of
diseases, it is a practical tool for identifying deficiencies in
our knowledge or service. This way the practice of EBLM initiates
quality improvement cycles and generates new research ideas as
well. EBLM, embedded into the culture of quality management in
laboratories, is �best practice� made explicit and accessible.
Accreditation according to high professional standards, based on
the best available research evidence, could be a powerful tool in
putting evidence into the daily practice of medical
laboratories.
References
- Burnett D (Ed.) Understanding Accreditation in Laboratory
Medicine. 1996. ACB Venture Publications. pp312.
- Parsley K. Corrigan P (eds) Quality improvement in health care.
Putting evidence into practice. 2ndedition. Stanley
Thornes (Publishers) Ltd. 1999. pp399.
- Preoperative tests: The use of routine preoperative tests for
elective surgery. Developed by the National Collaborating Centre
for Acute Care. National Institute for Clinical Excellence, London,
June 2003, pp18. www.nice.org.uk
- SIGN 50: A guideline developers� handbook. Scottish
Intercollegiate Guidelines Network, March 2004. www.sign.ac.uk/guidelines/fulltext/50/index.html
- ISO 15189:2003(E) Medical laboratories - Particular
requirements for quality and competence.
- Scrivener R, Morrel C, Baker R, Redsell S, Shaw E, Stevenson K,
Pink D, Bromwich N. Principles for Best Practice in Clinical Audit,
Radcliffe Medical Press Ltd, 2002, pp206.
- Ente BH. Joint Commission World Symposium on Improving Health
Care through Accreditation. Joint Comm J Qual Improvement 1999;
25(11):602-613.
- Oosterhuis WP, Bruns DE, Watine J, Sandberg S, Horvath AR.
Evidence-based guidelines in laboratory medicine: principles and
methods. Clin Chem 2004; 50:806-818.
- Horvath AR, Pewsner D. Systematic reviews in laboratory
medicine: principles, processes and practical considerations. Clin
Chim Acta 2004; 342: 23-39.
- Barth JH. The role of clinical audit. In: Evidence-based
Laboratory Medicine: From Principles to Practice. Price CP,
Christenson RH (eds) AACC Press, Washington. 2003; pp209-224.
- Bergus G, Vogelgesang S, Tansey J, Franklin E, Feld R.
Appraising and applying evidence about a diagnostic test during a
performance-based assessment. BMC Medical Education 2004; 4(20)
pp12. http://www.biomedcentral.com/1472-6920/4/20
- Beastall, GH, Gurr E, ten Kate J, Kenny D, Laitinen P. European
Communities Confederation of Clinical Chemistry & Laboratory
Medicine (EC4): Competence to be a Consultant in Clinical Chemistry
& Laboratory Medicine. Consultation Draft: April 2004
(unpublished)
- Price CP, Christenson RH. Teaching evidence-based laboratory
medicine: A cultural experience. In: Evidence-based Laboratory
Medicine: From Principles to Practice. Price CP, Christenson RH
(eds) AACC Press, Washington. 2003; pp 225-245.
- Smith CA, Ganschow PS, Reilly BM, Evans AT, McNutt RA, Osei A,
Saquib M, Surabhi S, Yadav S. Teaching residents evidence-based
medicine skills: a controlled trial of effectiveness and assessment
of durability. J Gen Intern Med 2000; 15: 710-5.
- Straus SE, Green ML, Bell DS, Badgett R, Davis D, Gerrity M,
Ortiz E, Shaneyfelt TM, Whelan C, Mangrulkar R. Evaluating the
teaching of evidence based medicine: conceptual framework. BMJ
2004; 329:1029-1032.
- McGinley PJ, Kilpatrick ES. Tumour markers: their use and
misuse by clinicians. Ann Clin Biochem 2003; 40: 643�647.
- Price CP. Evidence-based Laboratory Medicine: Supporting
Decision-Making. Clin Chem 2000; 46: 1041-1050.
- Mayer M, Wilkinson I, Heikkinen R, �rntoft T, Magid E. Improved
laboratory test selection and enhanced perception of test results
as tools for cost-effective medicine. Clin Chem Lab Med 1998; 36:
683-690.
- Smith BJ, McNeely MD. The influence of an expert system for
test ordering and interpretation on laboratory investigations. Clin
Chem 1999; 45:1168-75.
- Winkens RAG, Dinant G-J. Improving test ordering and diagnostic
cost-effectiveness in clinical practice � bridging the gap between
clinical research and routine health care. In: The Evidence Base of
Clinical Diagnosis. Knottnerus JA (ed) BMJ Books, 2002;
pp197-207.
- Bunting PS, van Walraven C. Effect of a controlled feedback
intervention on laboratory test ordering by community physician.
Clin Chem 2004; 50 (2): 321-326.
- Haeckel R, Wosniok W, Puentmann I. Discordance rate, a new
concept for combining diagnostic decisions with analytical
performance characteristics. 1. Application in method or sample
system comparisons and in defining decision limits. Clin Chem Lab
Med 2003; 41:347-55.
- Ricos C, Alvarez V, Cava F, Garcia-Lario JV, Hernandez A,
Jimenez CV, Minchinela J, Perich C, Simon M. Current databases on
biological variation: pros, cons and progress. Scand. J Clin Lab
Invest 1999; 59: 491-500.
- Fraser C. General strategies to set quality specifications for
reliablility performance characteristics. Scand J Clin Lab Invest
1999; 59: 487-90.
- Westgard JO. Why not evidence-based method specifications?
2002. (www.westgard.com/essay44.htm)
- Lim EM, Sikaris KA, Gill J, Calleja J, Hickman PE, Beilby J,
Vasikaran SD. Quality assessment of interpretative commenting in
clinical chemistry. Clin Chem 2004; 50:632�637.
- Kay JD. Communicating with clinicians. Ann Clin Biochem. 2001;
38: 103-110.
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