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Core outcome sets are critically important outcomes that should be measured in clinical trials. Their absence in atopic dermatitis is a form of research waste and impedes combining evidence to inform patient care. Here, we articulate the rationale for core outcome sets in atopic dermatitis and review the work of the international Harmonising Outcome Measures for Eczema group from its inception in Munich, 2010. We describe core domain determination (what should be measured), to instrument selection (how domains should be measured), culminating in the complete core outcome measurement set in Tokyo, 2019. Using a "road map," Harmonising Outcome Measures for Eczema includes diverse research methods including Delphi and nominal group techniques informed by systematic reviews of properties of candidate instruments. The 4 domains and recommended instruments for including in all clinical trials of atopic dermatitis are patient symptoms, measured by Patient-Oriented Eczema Measure and peak Numerical Rating Scale 11 for itch intensity over 24 hours, clinical signs measured using the Eczema Area and Severity Index, quality of life measured by the Dermatology Life Quality Index series for adults, children, and infants, and long-term control measured by either Recap of atopic eczema or Atopic Dermatitis Control Tool. [ABSTRACT FROM AUTHOR]

Background older people remain underrepresented in clinical trials, and evidence generated in younger populations cannot always be generalized to older patients. Objective to identify key barriers and to discuss solutions to specific issues affecting recruitment and retention of older participants in clinical trials based on experience gained from six current European randomised controlled trials (RCTs) focusing on older people. Methods a multidisciplinary group of experts including representatives of the six RCTs held two networking conferences and compiled lists of potential barriers and solutions. Every item was subsequently allocated points by each study team according to how important it was perceived to be for their RCTs. Results the six RCTs enrolled 7,612 older patients. Key barriers to recruitment were impaired health status, comorbidities and diverse health beliefs including priorities within different cultural systems. All trials had to increase the number of recruitment sites. Other measures felt to be effective included the provision of extra time, communication training for the study staff and a re-design of patient information. Key barriers for retention included the presence of severe comorbidities and the occurrence of adverse events. Long study duration, frequent study visits and difficulties accessing the study site were also mentioned. Solutions felt to be effective included spending more time maintaining close contact with the participants, appropriate measures to show appreciation and reimbursement of travel arrangements. Conclusion recruitment and retention of older patients in trials requires special recognition and a targeted approach. Our results provide scientifically-based practical recommendations for optimizing future studies in this population. [ABSTRACT FROM AUTHOR]

Objectives: The Outcome Measures in Rheumatology Initiative established the Contextual Factors Working Group to guide the understanding, identification and handling of contextual factors for clinical trials. In clinical research, different uses of the term 'contextual factors' exist. This study explores the perspectives of researchers (including clinicians) and patients in defining 'contextual factor' and its related terminology, identifying such factors and accounting for them in trials across rheumatology.Methods: We conducted individual semistructured interviews with researchers (including clinicians) who have experience within the field of contextual factors in clinical trials or other potentially relevant areas, and small focus group interviews with patients with rheumatic conditions. We transcribed the interviews and applied qualitative content analysis.Results: We interviewed 12 researchers and 7 patients. Researcher's and patient's descriptions of contextual factors were categorised into two broad themes, each comprising two contextual factors types. The 'treatment effect' theme focused on factors explaining variations in treatment effects (A) among patients and (B) among studies. The 'outcome measurement' theme focused on factors that explain (C) variations in the measurement result itself (apart from actual changes/differences in the outcome) and (D) variations in the outcome itself (beside treatment of interest). Methods for identifying and handling contextual factors differed among these themes and types.Conclusions: Two main themes for contextual factors with four types of contextual factors were identified based on input from researchers and patients. This will guide operationalisation of contextual factors. Further research should refine our findings and establish consensus among relevant stakeholders. [ABSTRACT FROM AUTHOR]

Objectives: To explore whether trial population characteristics modify treatment responses across various interventions, comparators and rheumatic conditions.Methods: In this meta-epidemiological study, we included trials from systematic reviews available from the Cochrane Musculoskeletal Group published up to 23 April 2019 in Cochrane Library with meta-analyses of five or more randomised controlled trials (RCTs) published from year 2000. From trial reports, we extracted data on 20 population characteristics. For characteristics with sufficient data (ie, available for ≥2/3 of the trials), we performed multilevel meta-epidemiological analyses.Results: We identified 19 eligible systematic reviews contributing 187 RCTs (212 comparisons). Only age and sex were explicitly reported in ≥2/3 of the trials. Using information about the country of the trials led to sufficient data for five further characteristics, that is, 7 out of 20 (35%) protocolised characteristics were analysed. The meta-regressions showed effect modification by economic status, place of residence, and, nearly, from healthcare system (explaining 4.8%, 0.9% and 1.5% of the between-trial variation, respectively). No effect modification was demonstrated from age, sex, patient education/health literacy or predominant religion.Conclusions: This study demonstrates the scarce reporting of most population characteristics, hampering investigation of their impact with meta-research. Our sparse results suggest that place of residence (ie, continent of the trial), economic status (based on World Bank classifications) and healthcare system (based on WHO index for health system performance) may be important in explaining the variation in treatment response across trials. There is an urgent need for consistent reporting of important population characteristics in trials.Prospero Registration Number: CRD42019127642. [ABSTRACT FROM AUTHOR]

Objective: The Contextual Factors Working Group aims to provide guidance on addressing contextual factors in rheumatology trials within OMERACT.Methods: During the Special Interest Group session at OMERACT 2018, preliminary results were presented from a case scenario survey and semistructured interviews, including contextual factors mentioned in these. A group-based exercise sought to identify and rank important generic contextual factors.Results: A total of 79 candidate factors were listed. Across the 3 groups, gender/sex, comorbidities, and the healthcare system were ranked as most important.Conclusion: The identified important contextual factor domains may be considered a provisional list pending further research. [ABSTRACT FROM AUTHOR]

Objective: To update the 1997 OMERACT-OARSI (Outcome Measures in Rheumatology-Osteoarthritis Research Society International) core domain set for clinical trials in hip and/or knee osteoarthritis (OA).Methods: An initial review of the COMET database of core outcome sets (COS) was undertaken to identify all domains reported in previous COS including individuals with hip and/or knee OA. These were presented during 5 patient and health professionals/researcher meetings in 3 continents (Europe, Australasia, North America). A 3-round international Delphi survey was then undertaken among patients, healthcare professionals, researchers, and industry representatives to gain consensus on key domains to be included in a core domain set for hip and/or knee OA. Findings were presented and discussed in small groups at OMERACT 2018, where consensus was obtained in the final plenary.Results: Four previous COS were identified. Using these, and the patient and health professionals/researcher meetings, 50 potential domains formed the Delphi survey. There were 426 individuals from 25 different countries who contributed to the Delphi exercise. OMERACT 2018 delegates (n = 129) voted on candidate domains. Six domains gained agreement as mandatory to be measured and reported in all hip and/or knee OA clinical trials: pain, physical function, quality of life, and patient's global assessment of the target joint, in addition to the mandated core domain of adverse events including mortality. Joint structure was agreed as mandatory in specific circumstances, i.e., depending on the intervention.Conclusion: The updated core domain set for hip and/or knee OA has been agreed upon. Work will commence to determine which outcome measurement instrument should be recommended to cover each core domain. [ABSTRACT FROM AUTHOR]

To standardize outcome reporting in clinical trials of patients with nonspecific low back pain, an international multidisciplinary panel recommended physical functioning, pain intensity, and health-related quality of life (HRQoL) as core outcome domains. Given the lack of a consensus on measurement instruments for these 3 domains in patients with low back pain, this study aimed to generate such consensus. The measurement properties of 17 patient-reported outcome measures for physical functioning, 3 for pain intensity, and 5 for HRQoL were appraised in 3 systematic reviews following the COSMIN methodology. Researchers, clinicians, and patients (n = 207) were invited in a 2-round Delphi survey to generate consensus (≥67% agreement among participants) on which instruments to endorse. Response rates were 44% and 41%, respectively. In round 1, consensus was achieved on the Oswestry Disability Index version 2.1a for physical functioning (78% agreement) and the Numeric Rating Scale (NRS) for pain intensity (75% agreement). No consensus was achieved on any HRQoL instrument, although the Short Form 12 (SF12) approached the consensus threshold (64% agreement). In round 2, a consensus was reached on an NRS version with a 1-week recall period (96% agreement). Various participants requested 1 free-to-use instrument per domain. Considering all issues together, recommendations on core instruments were formulated: Oswestry Disability Index version 2.1a or 24-item Roland-Morris Disability Questionnaire for physical functioning, NRS for pain intensity, and SF12 or 10-item PROMIS Global Health form for HRQoL. Further studies need to fill the evidence gaps on the measurement properties of these and other instruments. [ABSTRACT FROM AUTHOR]

Objective: To describe the perception of the current role of systemic glucocorticoids in the management of rheumatoid arthritis (RA) by examining their importance and the current level of evidence in recent guidelines, and to identify open questions to be addressed in future guidelines and research projects.Methods: We conducted a systematic literature review using the databases Ovid Embase, PubMed Medline, and Cochrane Library for guidelines on the pharmacologic treatment of RA. Retrieved articles were evaluated regarding their quality using the Appraisal of Guidelines for Research and Evaluation II tool and scrutinized for all relevant information concerning the use of glucocorticoids.Results: All guidelines agree that glucocorticoids, especially if given at low doses and for a short duration, are an appropriate option in the treatment of RA. However, many recommendations remain vague, as reliable and detailed evidence is scarce. Important aspects of glucocorticoid therapy are partially or completely neglected, and the existing nomenclature is not used uniformly. Quality evaluation revealed flaws in many articles, concerning not only glucocorticoid-specific recommendations but also guideline quality in general.Conclusion: Current recommendations for use of glucocorticoids in the management of RA are suboptimal. More rigorous evaluation of doses, timing, and duration of their use is needed. Existing nomenclature on glucocorticoid therapy should be used uniformly. [ABSTRACT FROM AUTHOR]

Objectives: To study the responsiveness of a combined power Doppler and greyscale ultrasound (PDUS) score for assessing synovitis in biologic-naïve patients with rheumatoid arthritis (RA) starting abatacept plus methotrexate (MTX).Methods: In this open-label, multicentre, single-arm study, patients with RA (MTX inadequate responders) received intravenous abatacept (∼10 mg/kg) plus MTX for 24 weeks. A composite PDUS synovitis score, developed by the Outcome Measures in Rheumatology-European League Against Rheumatism (OMERACT-EULAR)-Ultrasound Task Force, was used to evaluate individual joints. The maximal score of each joint was added into a Global OMERACT-EULAR Synovitis Score (GLOESS) for bilateral metacarpophalangeal joints (MCPs) 2-5 (primary objective). The value of GLOESS containing other joint sets was explored, along with clinical efficacy.Results: Eighty-nine patients completed the 24-week treatment period. The earliest PDUS sign of improvement in synovitis was at week 1 (mean change in GLOESS (MCPs 2-5): -0.7 (95% CIs -1.2 to -0.1)), with continuous improvement to week 24. Early improvement was observed in the component scores (power Doppler signal at week 1, synovial hyperplasia at week 2, joint effusion at week 4). Comparable changes were observed for 22 paired joints and minimal joint subsets. Mean Disease Activity Score 28 (C reactive protein) was significantly reduced from weeks 1 to 24, reaching clinical meaningful improvement (change ≥1.2) at week 8.Conclusions: In this first international prospective study, the composite PDUS score is responsive to abatacept. GLOESS demonstrated the rapid onset of action of abatacept, regardless of the number of joints examined. Ultrasound is an objective tool to monitor patients with RA under treatment.Trial Registration Number: NCT00767325. [ABSTRACT FROM AUTHOR]

Background: In cooperation with the Core Outcome Measures in Effectiveness Trials (COMET) initiative, the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) initiative aimed to develop a guideline on how to select outcome measurement instruments for outcomes (i.e., constructs or domains) included in a "Core Outcome Set" (COS). A COS is an agreed minimum set of outcomes that should be measured and reported in all clinical trials of a specific disease or trial population.Methods: Informed by a literature review to identify potentially relevant tasks on outcome measurement instrument selection, a Delphi study was performed among a panel of international experts, representing diverse stakeholders. In three consecutive rounds, panelists were asked to rate the importance of different tasks in the selection of outcome measurement instruments, to justify their choices, and to add other relevant tasks. Consensus was defined as being achieved when 70 % or more of the panelists agreed and when fewer than 15 % of the panelists disagreed.Results: Of the 481 invited experts, 120 agreed to participate of whom 95 (79 %) completed the first Delphi questionnaire. We reached consensus on four main steps in the selection of outcome measurement instruments for COS: Step 1, conceptual considerations; Step 2, finding existing outcome measurement instruments, by means of a systematic review and/or a literature search; Step 3, quality assessment of outcome measurement instruments, by means of the evaluation of the measurement properties and feasibility aspects of outcome measurement instruments; and Step 4, generic recommendations on the selection of outcome measurement instruments for outcomes included in a COS (consensus ranged from 70 to 99 %).Conclusions: This study resulted in a consensus-based guideline on the methods for selecting outcome measurement instruments for outcomes included in a COS. This guideline can be used by COS developers in defining how to measure core outcomes. [ABSTRACT FROM AUTHOR]

The European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases convened a task force of experts in rheumatoid arthritis (RA) and clinical trial methodology to comment on the new draft 'Guideline on clinical investigation of medicinal products for the treatment of RA' released by the European Medicines Agency (EMA). Special emphasis was placed by the group on the development of new drugs for the treatment of early RA. In the absence of a clear definition of early RA, it was suggested that clinical investigations in this condition were conducted in disease-modifying antirheumatic drugs naïve patients with no more than 1 year disease duration. The expert group recommended using an appropriate improvement in disease activity (American College of Rheumatology (ACR) or Simplified/Clinical Disease Activity Index (SDAI/CDAI) response criteria) or low disease activity (by any score) as primary endpoints, with ACR/European League Against Rheumatism remission as a secondary endpoint. Finally, as compelling evidence showed that the Disease Acrivity Score using 28-joint counts (DAS28) might not provide a reliable definition of remission, or sometimes even low disease activity, the group suggested replacing DAS28 as a measurement instrument to evaluate disease activity in RA clinical trials. Proposed alternatives included SDAI, CDAI and Boolean criteria. [ABSTRACT FROM AUTHOR]

Background Low back pain (LBP) is one of the most disabling and costly disorders affecting modern society, and approximately 90% of patients are labelled as having non-specific LBP (NSLBP). Several interventions for patients with NSLBP have been assessed in clinical trials, but heterogeneous reporting of outcomes in these trials has hindered comparison of results and performance of meta-analyses. Moreover, there is a risk of selective outcome reporting bias. To address these issues, the development of a core outcome set (COS) that should be measured in all clinical trials for a specific health condition has been recommended. A standardized set of outcomes for LBP were proposed in 1998 however, with evolution in COS development methodology, new instruments, interventions, and understanding of measurement properties, it is appropriate to update that proposal. This protocol describes the methods used in the initial step in developing a COS for NSLBP, namely, establishing a core domain set that should be measured in all clinical trials. Methods/Design An International Steering Committee including researchers, clinicians, and patient representatives from four continents was formed to guide the development of this COS. The approach of initiatives like Core Outcome Measures in Effectiveness Trials (COMET) and Outcome Measures in Rheumatology (OMERACT) was followed. Participants were invited to participate in a Delphi study aimed at generating a consensus-based core domain set for NSLBP. A list of potential core domains was drafted and presented to the Delphi participants who were asked to judge which domains were core. Participant suggestions about overlap, aggregation, or addition of potential core domains were addressed during the study. The patients' responses were isolated to assess whether there was substantial disagreement with the rest of the Delphi panel. A priori thresholds for consensus were established before each Delphi round. All participants' responses were analysed from a quantitative and qualitative perspective to ascertain that no substantial discrepancies between the two approaches emerged. Discussion We present the initial step in developing a COS for NSLBP. The next step will be to determine which measurement instruments adequately cover the domains. [ABSTRACT FROM AUTHOR]

Background: Lack of standardization of outcome measures limits the usefulness of clinical trial evidence to inform health care decisions. This can be addressed by agreeing on a minimum core set of outcome measures per health condition, containing measures relevant to patients and decision makers. Since 1992, the Outcome Measures in Rheumatology (OMERACT) consensus initiative has successfully developed core sets for many rheumatologic conditions, actively involving patients since 2002. Its expanding scope required an explicit formulation of its underlying conceptual framework and process. Methods: Literature searches and iterative consensus process (surveys and group meetings) of stakeholders including patients, health professionals, and methodologists within and outside rheumatology. Results: To comprehensively sample patient-centered and intervention-specific outcomes, a framework emerged that comprises three core ''Areas,'' namely Death, Life Impact, and Pathophysiological Manifestations; and one strongly recommended Resource Use. Through literature review and consensus process, core set development for any specific health condition starts by identifying at least one core ''Domain'' within each of the Areas to formulate the ''Core Domain Set.'' Next, at least one applicable measurement instrument for each core Domain is identified to formulate a ''Core Outcome Measurement Set.'' Each instrument must prove to be truthful (valid), discriminative, and feasible. In 2012, 96% of the voting participants (n5125) at the OMERACT 11 consensus conference endorsed this model and process. Conclusion: The OMERACT Filter 2.0 explicitly describes a comprehensive conceptual framework and a recommended process to develop core outcome measurement sets for rheumatology likely to be useful as a template in other areas of health care. [ABSTRACT FROM AUTHOR]

Background The development and application of standardised sets of outcomes to be measured and reported in clinical trials have the potential to increase the efficiency and value of research. One of the most notable of the current outcome sets began nearly 20 years ago: the World Health Organization and International League of Associations for Rheumatology core set of outcomes for rheumatoid arthritis clinical trials, originating from the OMERACT (Outcome Measures in Rheumatology) Initiative. This study assesses the use of this core outcome set by randomised trials in rheumatology. Methods An observational review was carried out of 350 randomised trials for the treatment of rheumatoid arthritis identified through the The Cochrane Library (up to and including September 2012 issue). Reports of these trials were evaluated to determine whether or not there were trends in the proportion of trials reporting on the full set of core outcomes over time. Researchers who conducted trials after the publication of the core set were contacted to assess their awareness of it and to collect reasons for non-inclusion of the full core set of outcomes in the study. Results Since the introduction of the core set of outcomes for rheumatoid arthritis, the consistency of measurement of the core set of outcomes has improved, although variation in the choice of measurement instrument remains. The majority of trialists who responded said that they would consider using the core outcome set in the design of a new trial. Conclusions This observational review suggests that a higher percentage of trialists conducting trials in rheumatoid arthritis are now measuring the rheumatoid arthritis core outcome set. Core outcome sets have the potential to improve the evidence base for health care, but consideration must be given to the methods for disseminating their availability amongst the relevant communities. [ABSTRACT FROM AUTHOR]

The use of nonstandardized and inadequately validated outcome measures in atopic eczema trials is a major obstacle to practising evidence-based dermatology. The Harmonising Outcome Measures for Eczema ( HOME) initiative is an international multiprofessional group dedicated to atopic eczema outcomes research. In June 2011, the HOME initiative conducted a consensus study involving 43 individuals from 10 countries, representing different stakeholders (patients, clinicians, methodologists, pharmaceutical industry) to determine core outcome domains for atopic eczema trials, to define quality criteria for atopic eczema outcome measures and to prioritize topics for atopic eczema outcomes research. Delegates were given evidence-based information, followed by structured group discussion and anonymous consensus voting. Consensus was achieved to include clinical signs, symptoms, long-term control of flares and quality of life into the core set of outcome domains for atopic eczema trials. The HOME initiative strongly recommends including and reporting these core outcome domains as primary or secondary endpoints in all future atopic eczema trials. Measures of these core outcome domains need to be valid, sensitive to change and feasible. Prioritized topics of the HOME initiative are the identification/development of the most appropriate instruments for the four core outcome domains. HOME is open to anyone with an interest in atopic eczema outcomes research. [ABSTRACT FROM AUTHOR]

Abstract: Background: In the setting of multiple remission and relapse periods of a chronic disease, simple endpoint analysis does not fully capture all relevant information, and we need methods to additionally describe both the duration of remission as well as the interruptions in this desired state. Probably the two-state continuous Markov process model comprises the best mathematical approach to data analysis. However, this approach is complex and not intuitive to clinicians. In this paper we propose a simple scoring system and a graph that can enhance the information about the remission experience in a trial or cohort study. Methods: The continuity rewarded (‘ConRew’) score sums up periods in remission, and rewards extended periods by placing more value on uninterrupted periods than on interrupted periods. The ‘patient vector graph’ attempts to plot each patient''s remission experience over time as a horizontal line (the ‘vector’) that is visible when the patient is in remission, but interrupted whenever relapse occurs. In this way a pattern is formed that conveys the number of patients experiencing remission, their individual total duration and interruptions, and time when these occur. Results: In a dataset of a randomized trial in early rheumatoid arthritis, the graph clearly showed both early and late benefit of one group over the other. The scoring system demonstrated the main benefit was in the number of remission periods, not in their ‘uninterruptedness’. Conclusion: Both approaches proved feasible and added extra information. [Copyright &y& Elsevier]

The article presents a study which examines the effects and safety of selective estrogen receptor α (ERα) agonist Org 37663 in rheumatoid arthritis (RA) patients. It states that a 10-week, randomized, and proof-of-concept trial was initiated in RA postmenopausal female patients who receive background treatment with methotrexate or sulfasalazine. The results showed that Org 37663 was safe and well tolerated, but was not effective in influencing the disease activity in RA patients.

The development of valid outcome measures is essential for appropriate management of any condition, but particularly chronic rheumatic diseases, such as rheumatoid arthritis. Over the last 15 years, Outcome Measures in Arthritis Clinical Trials has been dedicated to developing such measures in a variety of musculoskeletal conditions, including rheumatoid arthritis, osteoarthritis, osteoporosis, ankylosing spondylitis and gout. [ABSTRACT FROM AUTHOR]

OMERACT is the acronym for an international, informally organized network initiated in 1992 aimed at improving outcome measurement in rheumatology. Chaired by an executive committee, it organizes consensus conferences in a 2-yearly cycle that circles the globe. Data driven recommendations are prepared and updated by expert working groups. Recommendations include core sets of measures for most of the major rheumatologic conditions. Since 2002 patients have been actively engaged in the process. [ABSTRACT FROM AUTHOR]

This article provides evidence from the OMERACT (Outcome Measures in RheumAtology Clinical Trials) consensus conferences on patient-reported pain as a key outcome measure for most rheumatologic diseases, including rheumatoid arthritis, osteoarthritis, osteoporosis, back disorders, ankylosing spondylitis, and lupus. These core sets have been endorsed internationally by the World Health Organization, the International League Against Rheumatism, the US National Osteoporosis Foundation, and the OsteoArthritis Research Society International (OARSI). Future research will assess methods for improving interpretability of pain outcomes for patients and clinicians. These methods include determining minimal clinically important differences and number needed to treat (NNT) for continuous outcomes such as pain. [ABSTRACT FROM AUTHOR]

A correction to the article "Core outcome domains for clinical trials in non-specific low back pain" that was published in the April 29, 2015 issue is presented.

The article discusses the need to conduct large, simple, pragmatic trials for the treatment of rheumatoid arthritis due to lack of enough evidence that will guide the choice of treatment for this disease. The pragmatic trials must be designed to determine the best way to treat rheumatoid arthritis as well as how to approach comorbidity and how patients should be monitored.

Comments on pharmaceutical clinical research. Evidence of bias in some trials due to pressure from sponsors; Efforts of editors of medical journals to make requirements for study authors more stringent; Suggestion that masked analyses should be used.

Abstract: Objective: To investigate areas of consensus and disagreement among Dutch physiatrists concerning prescription of therapeutic footwear for the neuropathic foot and to develop a research agenda. Study Design and Setting: Forty participants were physiatrists and experts in the field of orthopedic shoe techniques. Four postal Delphi rounds were followed by a final plenary session. Results: Forty of the 44 invited experts participated in all postal Delphi rounds, with an overall response of 100%. They achieved consensus on the following. 1. (Dutch) Terminology for two sets of domains and dimensions for the various features of the neuropathic foot and for the shoe characteristics. 2. Application of specific shoe components: insole, shaft, outsole, tongue, and heel. In most features of the neuropathic foot, shaft and outsole domains were linked in the flexibility dimension. 3. Shoe prescriptions for various features of the neuropathic foot in at least four technical domains. Experts disagreed on application of rocker bar and shaft height. In a final conference, 31 experts agreed on a prioritized research agenda. Conclusion: An intensive Delphi process yielded consensus on terminology, and determined areas of consensus and disagreement for future research for the various features of the neuropathic foot and the shoe characteristics. [Copyright &y& Elsevier]