Andrea Rita Horvath

Guidelines and Recommendations for Laboratory Analysis in the Diagnosis and Management of Diabetes Mellitus

BACKGROUND Multiple laboratory tests are used to diagnose and manage patients with diabetes mellitus. The quality of the scientific evidence supporting the use of these tests varies substantially. APPROACH An expert committee compiled evidence-based recommendations for the use of laboratory testing for patients with diabetes. A new system was developed to grade the overall quality of the evidence and the strength of the recommendations. Draft guidelines were posted on the Internet and presented at the 2007 Arnold O. Beckman Conference. The document was modified in response to oral and written comments, and a revised draft was posted in 2010 and again modified in response to written comments. The National Academy of Clinical Biochemistry and the Evidence Based Laboratory Medicine Committee of the AACC jointly reviewed the guidelines, which were accepted after revisions by the Professional Practice Committee and subsequently approved by the Executive Committee of the American Diabetes Association. CONTENT In addition to long-standing criteria based on measurement of plasma glucose, diabetes can be diagnosed by demonstrating increased blood hemoglobin A(1c) (Hb A(1c)) concentrations. Monitoring of glycemic control is performed by self-monitoring of plasma or blood glucose with meters and by laboratory analysis of Hb A(1c). The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of autoantibodies, urine albumin, insulin, proinsulin, C-peptide, and other analytes are addressed. SUMMARY The guidelines provide specific recommendations that are based on published data or derived from expert consensus. Several analytes have minimal clinical value at present, and their measurement is not recommended.

Defining analytical performance specifications: Consensus Statement from the 1st Strategic Conference of the European Federation of Clinical Chemistry and Laboratory Medicine.

*Corresponding author: Sverre Sandberg, Norwegian Quality Improvement of Primary Care Laboratories (Noklus), Institute of Global Public Health and Primary Health Care, University of Bergen and Laboratory of Clinical Biochemistry, Bergen, Norway, E-mail: sverre.sandberg@isf.uib.no Callum G. Fraser: Centre for Research into Cancer Prevention and Screening, University of Dundee, Ninewells Hospital and Medical School, Dundee, Scotland, UK Andrea Rita Horvath: SEALS Department of Clinical Chemistry, Prince of Wales Hospital, Screening and Test Evaluation Program, School of Public Health, University of Sydney, and School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia Rob Jansen: Netherlands Foundation for Quality Assessment of Medical Laboratories (SKML), Radboud University, Nijmegen, The Netherlands Graham Jones: SydPath, St Vincent’s Hospital, Sydney, NSW, Australia Wytze Oosterhuis: Atrium-Orbis, Department of Clinical Chemistry and Haematology, Heerlen, The Netherlands Per Hyltoft Petersen: Norwegian Quality Improvement of Primary Care Laboratories (Noklus), Institute of Global Public Health and Primary Health Care, University of Bergen, Norway Heinz Schimmel: European Commission, Joint Research Centre, Institute for Reference Materials and Measurements (IRMM), Geel, Belgium Ken Sikaris: Sonic Healthcare and Melbourne University, Melbourne, Vic, Australia Mauro Panteghini: Centre for Metrological Traceability in Laboratory Medicine (CIRME), University of Milan, Milan, Italy Consensus Statement

Position Statement Executive Summary: Guidelines and Recommendations for Laboratory Analysis in the Diagnosis and Management of Diabetes Mellitus

BACKGROUND Multiple laboratory tests are used in the diagnosis and management of patients with diabetes mellitus. The quality of the scientific evidence supporting the use of these assays varies substantially. APPROACH An expert committee compiled evidence-based recommendations for the use of laboratory analysis in patients with diabetes. A new system was developed to grade the overall quality of the evidence and the strength of the recommendations. A draft of the guidelines was posted on the Internet, and the document was modified in response to comments. The guidelines were reviewed by the joint Evidence-Based Laboratory Medicine Committee of the AACC and the National Academy of Clinical Biochemistry and were accepted after revisions by the Professional Practice Committee and subsequent approval by the Executive Committee of the American Diabetes Association. CONTENT In addition to the long-standing criteria based on measurement of venous plasma glucose, diabetes can be diagnosed by demonstrating increased hemoglobin A1c (HbA1c) concentrations in the blood. Monitoring of glycemic control is performed by the patients measuring their own plasma or blood glucose with meters and by laboratory analysis of HbA1c. The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of autoantibodies, urine albumin, insulin, proinsulin, C-peptide, and other analytes are addressed. SUMMARY The guidelines provide specific recommendations based on published data or derived from expert consensus. Several analytes are found to have minimal clinical value at the present time, and measurement of them is not recommended.

From biomarkers to medical tests: the changing landscape of test evaluation.

Regulators and healthcare payers are increasingly demanding evidence that biomarkers deliver patient benefits to justify their use in clinical practice. Laboratory professionals need to be familiar with these evidence requirements to better engage in biomarker research and decisions about their appropriate use. This paper by a multidisciplinary group of the European Federation of Clinical Chemistry and Laboratory Medicine describes the pathway of a laboratory assay measuring a biomarker to becoming a medically useful test. We define the key terms, principles and components of the test evaluation process. Unlike previously described linearly staged models, we illustrate how the essential components of analytical and clinical performances, clinical and cost-effectiveness and the broader impact of testing assemble in a dynamic cycle. We highlight the importance of defining clinical goals and how the intended application of the biomarker in the clinical pathway should drive each component of test evaluation. This approach emphasizes the interaction of the different components, and that clinical effectiveness data should be fed back to refine analytical and clinical performances to achieve improved outcomes. The framework aims to support the understanding of key stakeholders. The laboratory profession needs to strengthen collaboration with industry and experts in evidence-based medicine, regulatory bodies and policy makers for better decisions about the use of new and existing medical tests.

Electrochemotherapy of cutaneous metastases of melanoma - A case series study and systematic review of the evidence

OBJECTIVES Electrochemotherapy (ECT) is a novel therapeutic option for the treatment of cutaneous and subcutaneous metastases of malignant melanoma. During the treatment, electric pulses are applied to tumor nodules to deliver nonpermeant or poorly permeant chemotherapeutic agents into the cells, increasing local cytotoxicity of anticancer drugs. We compared the clinical effectiveness of ECT as an alternative palliative treatment option for unresectable metastatic lesions of malignant melanoma with a systematic review of reported outcomes. METHODS One hundred fifty-eight cutaneous and subcutaneous metastases of nine patients were treated with ECT. All treatments were performed under general anesthesia using intravenous bleomycin injection. Median follow-up was 195 days. RESULTS In our case series, complete response rate was 23%, and partial response rate was 39%. We observed no change in 30% and progressive disease in 8% of cases. CONCLUSIONS ECT is a simple and effective treatment of single or multiple cutaneous and subcutaneous metastases of melanoma with minimal side effects. Our results provide further data for the growing body of evidence in recently published studies that ECT used for palliation has clinical benefit. The authors have indicated no significant interest with commercial supporters.

How can we teach EBM in clinical practice?? An analysis of barriers to implementation of on-the-job EBM teaching and learning

Introduction: Evidence-based medicine (EBM) improves the quality of health care. Courses on how to teach EBM in practice are available, but knowledge does not automatically imply its application in teaching. We aimed to identify and compare barriers and facilitators for teaching EBM in clinical practice in various European countries. Methods: A questionnaire was constructed listing potential barriers and facilitators for EBM teaching in clinical practice. Answers were reported on a 7-point Likert scale ranging from not at all being a barrier to being an insurmountable barrier. Results: The questionnaire was completed by 120 clinical EBM teachers from 11 countries. Lack of time was the strongest barrier for teaching EBM in practice (median 5). Moderate barriers were the lack of requirements for EBM skills and a pyramid hierarchy in health care management structure (median 4). In Germany, Hungary and Poland, reading and understanding articles in English was a higher barrier than in the other countries. Conclusion: Incorporation of teaching EBM in practice faces several barriers to implementation. Teaching EBM in clinical settings is most successful where EBM principles are culturally embedded and form part and parcel of everyday clinical decisions and medical practice.

Postanalytical external quality assessment of urine albumin in primary health care: an international survey.

BACKGROUND Microalbuminuria (MA) is recognized as an important risk factor for cardiovascular and renal complications in diabetes. We sought to evaluate how screening for MA is conducted and how urine albumin (UA) results are interpreted in primary care internationally. METHODS General practitioners (GPs) received a case history-based questionnaire depicting a male type 2 diabetes patient in whom UA testing had not been performed. Questions were related to type of urine sample used for UA testing, need for a repeat test, whether UA testing was performed in the office laboratory, and what changes in UA results were considered clinically important [critical difference (CD)]. Participants received national benchmarking feedback reports. RESULTS We included 2078 GPs from 9 European countries. Spot urine samples were used most commonly for first time office-based testing, whereas timed collections were used to a larger extent for hospital-based repeat tests. Repeat tests were requested by 45%-77% of GPs if the first test was positive. Four different measurement units were used by 70% of participants in estimating clinically important changes in albumin values. Stated CDs varied considerably among GPs, with similar variations in each country. A median CD of 33% was considered clinically important for both improvement and deterioration in MA, corresponding to an achievable analytical imprecision of 14%, when UA is reported as an albumin/creatinine ratio. CONCLUSIONS Guidelines on diagnosing MA are followed only partially, and should be made more practicable, addressing issues such as type of samples, measurement units, and repeat tests.

Harmonization of critical result management in laboratory medicine.

Unsafe medical care is a major source of disabling injuries and death throughout the world. The failure to notify, follow up, and action critical results, which signify life threatening situations, is of particular concern and may cause avoidable morbidity and mortality. International accreditation standards require pathology laboratories to have a system for the timely and reliable communication of critical results to clinical personnel responsible for patient care. In response, various practices and a number of different terminologies have been described in the literature. Increased attention to patient safety standards and multinational surveys, however, highlighted shortcomings and inefficiencies in existing communication systems. These failures and variations in practice call for clear guidance and harmonization of approaches in order to improve communications and to provide safer patient care. The objectives of this review are to create a harmonized terminology and to learn from international practices by systematically reviewing the best available evidence on existing approaches. Based on literature review findings we highlight key areas where harmonization is necessary and feasible and offer a conceptual framework and methods for designing better and more evidence-based systems for the timely notification of laboratory results that represent potential patient safety hazards.

Setting analytical performance specifications based on outcome studies – is it possible?

Abstract The 1st Strategic Conference of the European Federation of Clinical Chemistry and Laboratory Medicine proposed a simplified hierarchy for setting analytical performance specifications (APS). The top two levels of the 1999 Stockholm hierarchy, i.e., evaluation of the effect of analytical performance on clinical outcomes and clinical decisions have been proposed to be replaced by one outcome-based model. This model can be supported by: (1a) direct outcome studies; and (1b) indirect outcome studies investigating the impact of analytical performance of the test on clinical classifications or decisions and thereby on the probability of patient relevant clinical outcomes. This paper reviews the need for outcome-based specifications, the most relevant types of outcomes to be considered, and the challenges and limitations faced when setting outcome-based APS. The methods of Model 1a and b are discussed and examples are provided for how outcome data can be translated to APS using the linked evidence and simulation or decision analytic techniques. Outcome-based APS should primarily reflect the clinical needs of patients; should be tailored to the purpose, role and significance of the test in a well defined clinical pathway; and should be defined at a level that achieves net health benefit for patients at reasonable costs. Whilst it is acknowledged that direct evaluations are difficult and may not be possible for all measurands, all other forms of setting APS should be weighed against that standard, and regarded as approximations. Better definition of the relationship between the analytical performance of tests and health outcomes can be used to set analytical performance criteria that aim to improve the clinical and cost-effectiveness of laboratory tests.

Guidelines for the use of biomarkers: Principles, processes and practical considerations

Abstract With the growing availability of new health care technologies and rapidly emerging biomarker discoveries, clinicians need advice on the clinical validity and utility of new tests and whether they improve clinical, patient-centred, organizational or economic outcomes. High quality clinical practice guidelines (CPGs), based on well-designed and conducted test evaluation studies, are tools for translating research into practice and in promoting a value- and evidence-based approach for clinical utilization and reimbursement of new biomarkers. Such study protocols should be appropriate for the questions addressed at each stage of biomarker development: 1/ Basic research into the association of disease with the new biomarker; 2/ Modelling the potential use of the new biomarker in clinical practice; Studies on the 3/ analytic validity; 4/ clinical validity (efficacy); 5/ clinical utility (effectiveness); and 6/ clinical impact (efficiency) of testing. Irrespective of the facts that CPGs potentially influence important clinical decisions and thus patient outcomes, current approaches to CPG development often do not follow the rigorous processes of scientific publications. Guidelines should be outcome oriented; reliable and free from any forms of bias; based on high quality research or on formal consensus when evidence is conflicting or lacking; multidisciplinary; flexible and applicable to various clinical circumstances and patient preferences; clear; cost-effective; appropriately disseminated and implemented; amenable to measurement of their impact in practice; and regularly reviewed and updated. Therefore until guideline-making and reporting standards are improved, all CPGs should be carefully scrutinized for methodological and content validity before being adopted, adapted and used in clinical practice.