Department of Pneumology, University Hospital of Cattinara, Trieste, and 2Cardio-Pulmonary Rehabilitation, S. Sebastiano Hospital, Correggio, Reggio Emilia, Italy



Background and objective: Exacerbations of COPD are often characterized by increased mucus production that is difficult to treat and worsens patients’ outcome. This study evaluated the efficacy of a chest physiotherapy technique (expiration with the glottis open in the lateral posture, ELTGOL) during acute exacerbations of COPD using as outcome measures sputum volume, length of hospitalization, reduction in dyspnoea (Borg score), improvement in quality of life (assessed by the St George Respiratory Questionnaire) and incidence of COPD exacerbations during follow up. Methods: The study recruited 59 patients hospitalized for the treatment of acute exacerbation of COPD, who were randomly assigned to a control group and an intervention group. The control group was treated with standard medical therapy while the intervention group was treated with ELTGOL plus medical therapy. A subgroup of patients was followed for 6 months to verify the effects on COPD exacerbations and need for hospitalizations. Results: At the time of hospital discharge there was no significant difference between the two groups in the outcome measures, with the exception of the Borg score, which was significantly improved in the ELTGOL group (4.3 ⫾ 1.5 in the control group vs 3.0 ⫾ 1.8 in the ELTGOL group, P = 0.004). After 6 months there was no significant difference in the other measured parameters between a subset of the groups available for follow up. During follow up, the ELTGOL group had numerically fewer exacerbations and less need for hospitalization though differences were not statistically significant. Conclusions: Chest physiotherapy using the ELTGOL technique has a limited role in patients with mild exacerbation of moderate to severe COPD

A chest physiotherapy technique (expiration with the glottis open in the lateral posture, ELTGOL) plus medical treatment was compared with medical treatment alone in the care of patients hospitalized with an acute exacerbation of COPD. Based on various parameters there was no significant improvement in recovery from the use of ELTGOL. with a tendency towards fewer exacerbations and hospitalizations. Key words: COPD, drainage technique, ELTGOL, exacerbation, respiratory physiotherapy, secretion.


Correspondence: Metka Kodric, Department of Pneumology, University Hospital of Cattinara, Strada di Fiume 447, Trieste, Italy. Email: [email protected] Received 9 January 2008; invited to revise 13 February 2008, 27 May 2008, 23 August 2008; revised 28 April 2008, 11 July 2008, 1 September 2008; accepted 19 September 2008 (Associate Editor: Helen Reddel).

COPD is characterized by cough and sputum production. Exacerbations of the disease1 may lead to long-term hospitalizations and high costs. Factors influencing outcomes include the presence of bronchial secretions that limit respiratory function and, in many severe cases, the use of non-invasive mechanical ventilation. Medical therapies alone (systemic steroids, bronchodilators, antibiotics and mucolytics) often do not result in rapid improvement in symptoms. Chest physiotherapy2 is an integral part of pulmonary rehabilitation programmes and includes several techniques of secretion clearance. These techniques are often used in intensive care unit settings,3 for patients affected by acute atelectasis due to mucus plugging. The potential benefit of chest physiotherapy for patients with COPD has been well documented; these studies, however, were performed in patients who were clinically stable.4 The current literature does not contain reports of studies examining the efficacy of these techniques in patients hospitalized with COPD exacerbations.5–6 The aim of this randomized controlled study was to evaluate whether the routine use of a particular drainage technique, namely expiration with the glottis

© 2009 The Authors Journal compilation © 2009 Asian Pacific Society of Respirology

Respirology (2009) 14, 424–428 doi: 10.1111/j.1440-1843.2008.01466.x


ELTGOL in COPD exacerbations

open in the lateral posture (ELTGOL),7 may benefit patients affected by COPD exacerbation.

METHODS Patients The study recruited 59 COPD patients (41 men and 18 women, aged 70.2 ⫾ 8.4 years), hospitalized with an acute exacerbation between March and September 2002. Informed consent was given by each patient according to the policy of the local Ethics Committee. The Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria were used to define COPD.8 Acute exacerbation of COPD was defined on the basis of the clinical history, physical examination and CXR and the severity score according to the Anthonisen Criteria.9 Throughout the study, medical treatment was standardized in all patients according to GOLD guidelines.8 Treatment included nebulized salbutamol (5 mg every 4 h), nebulized ipratropium bromide (500 mg every 6 h), intravenous methylprednisolone (40 mg every day) and antibiotic coverage. Patients were discharged after the resolution of the exacerbation. Patient exclusion criteria were: positive bronchodilator reversibility test or any other chest disease likely to bias results.

Study design The study was a randomized controlled trial. After giving informed consent, patients were randomly assigned to two groups. Group A, the control group, was treated with standard medical therapy alone (steroids, bronchodilators and antibiotics) according to the GOLD guidelines;8 group B (ELTGOL-study group) was given standard medical therapy and chest physiotherapy (ELTGOL). After 7 days of treatment, patients in the ELTGOL group were continued on standard medical treatment alone until hospital discharge. No patient in either group was enrolled in educational and home programmes as they are not routinely performed in our practice.

Chest physiotherapy Chest physiotherapy was performed by a trained specialist respiratory therapist, twice daily for seven consecutive days. It was administered for 30 min at the same time each day, after inhaled medications. Patients were positioned on their side and performed ELTGOL. This is an active assisted technique to mobilize bronchial secretions in the lateral decubitus position on both right and left sides by dependent ventilation, with the peripheral airways clearance facilitated by slow expiratory manoeuvres. The first step of this technique involves the patient learning to relax. The patient then breathes from FRC to RV. The patient is helped by the physiotherapist who, standing behind, exerts an abdominal push with one hand © 2009 The Authors Journal compilation © 2009 Asian Pacific Society of Respirology

and counterbraces at the level of the supra-lateral costal wall with the other hand, to obtain the most complete infra-lateral lung deflation. The expiratory flow rate is controlled to avoid airways collapse. The total time spent by therapists per patient was the same (30–40 min for each session). The arterial oxygen saturation (SpO2) was monitored during treatment with a pulse oximeter (MiniOx V, MSA, Owings Mills, MD, USA). Sputum was collected for one hour after the end of the physiotherapy session. Total sputum volume, including salivary content, was recorded with a graded glass to measure the exact amount during a 24-h period.

Measurements Patients had the following tests performed at hospital admission and discharge: (i) spirometry: flows and dynamic volumes were evaluated by simple spirometry (SensorMedics 6200, Autobox DL; SensorMedics Corp., Yorba Linda, CA, USA), and FEV1 and FEV1/FVC were evaluated; (ii) arterial oxygen saturation (SpO2) was monitored with a pulse oximeter (MiniOx V, MSA); (iii) arterial blood gases (ABG): samples were collected by radial puncture while patients were breathing room air and analysed by haemogasanalyser (Chiron 845); and (iv) dyspnoea measurements: MRC scale (5 steps) for chronic dyspnoea and the Borg scale (10 steps) during exercise were used. No specific exercise was considered or exercise programmes scheduled; patients were permitted to freely move and simple activities were encouraged. Health measurements: quality of life (QoL) was assessed by St George Respiratory Questionnaire10 at admission, at discharge and 1 month after discharge; A subgroup of patients was followed for 6 months in order to assess acute exacerbations of COPD and hospitalizations. The flow diagram of the study is represented in Figure 1.

End-points and statistics The primary end-point to determine the efficacy of ELTGOL, compared with standard treatment, was sputum volume. Secondary end-points were: (i) length of hospitalization, (ii) incidence of COPD exacerbation during follow up, (iii) dyspnoea reduction, and (iv) QoL improvement. Values are presented as mean ⫾ SD. Normal distribution was assessed by means of the Kolmogorov– Smirnov test. Normally distributed data were analysed with the paired t-test. Non-normally distributed data were analysed by means of Wilcoxon signed ranks test. Comparisons between the two groups were performed using the unpaired t-test for normally distributed data and the Mann–Whitney test for nonnormally distributed data. A post hoc analysis was performed, comparing patients whose daily sputum production was more than 25 mL. Categorical data were analysed by the chi-square test. A Bonferroni correction was applied and the adjusted significance level was estimated to be 0.007. A survival curve Respirology (2009) 14, 424–428


M Kodric et al.

Figure 1 Flow diagram of the study comparing standard medical treatment versus standard medical treatment together with the ELTGOL (expiration with the glottis open in the lateral posture) drainage technique.

Table 1 Comparison of respiratory parameters at hospital admission and at discharge in the control group (Group A), which received standard medical therapy, and the intervention group (Group B), which received a chest physiotherapy intervention (expiration with the glottis open in the lateral posture—ELTGOL) plus standard medical therapy Group A—Control (n = 29 patients)

FEV1, % of predicted FEV1/FVC, % SpO2, % Sputum, mL/day Borg score MRC score SGRQ score

Group B—ELTGOL (n = 30 patients)

A vs B Discharge








52.3 ⫾ 18.7 47.4 ⫾ 12.8 89.6 ⫾ 7.5 13.6 ⫾ 13.6 4.6 ⫾ 2.0 3.0 ⫾ 1.2 57.4 ⫾ 18.7

57.9 ⫾ 23.9 47.4 ⫾ 14.2 92.1 ⫾ 3.4 8.2 ⫾ 9.4 4.3 ⫾ 1.5 2.9 ⫾ 1.1 54.4 ⫾ 19.2

0.008 0.823 0.030 0.001 0.074 0.375 0.074

55.6 ⫾ 27.6 50.9 ⫾ 13.1 90.0 ⫾ 6.3 19.5 ⫾ 17.2 5.2 ⫾ 2.7 2.9 ⫾ 1.3 59.1 ⫾ 17.3

64.4 ⫾ 34.0 52.9 ⫾ 14.6 93.1 ⫾ 2.9 6.8 ⫾ 7.6 3.0 ⫾ 1.8 2.5 ⫾ 1.4 54.7 ⫾ 17.7

0.001 0.127 0.002 <0.001 <0.001 0.005 0.012

0.405 0.152 0.310 0.703 0.004 0.332 0.961

Data are presented as mean ⫾ SD. MRC, Medical Research Council; SGRQ, St George Respiratory Questionnaire; SpO2, arterial oxymetry saturation.

(time-to-event) analysis for exacerbation and hospitalization was performed for all the patients initially enrolled in the study and the log-rank test was used to asses the differences between curves. A P-value of less than 0.05 was considered significant. Statistical analysis was performed using Statview (Version 5.0.1., SAS Institute Inc., SAS Campus Drive, Cary, NC 27513, USA) and MedCalc (Version, MedCalc Software, Mariakerke, Belgium).

RESULTS The 59 eligible patients were randomly assigned to a control group (Group A, n = 29) and a study group (Group B, n = 30) and the respiratory parameters of each group at admission and discharge are shown in Table 1. Other relevant data at admission, for the ELTGOL group and control group, respectively, are: gender ratio, (M/F) 20/10 vs 21/8; age, 71.3 ⫾ 8.4 vs 69.1 ⫾ 8.3 years; BMI, 24.6 ⫾ 4.8 vs 26.0 ⫾ 5.4 kg; paO2, 60.1 ⫾ 11.4 vs 61.5 ⫾ 11.6 mm Hg; and paCO2, 44.1 ⫾ 8.9 vs 44.6 ⫾ 12.4 mm Hg. Respirology (2009) 14, 424–428

ELTGOL was well tolerated by the study group. No complications occurred. The amount of sputum produced in 24 h decreased significantly in both groups but no significant difference between the groups was recorded at discharge (Table 1). Among the 21 patients producing more than 25 mL of sputum per day at admission (ELTGOL group n = 10, control group n = 11), a larger reduction in sputum volume was seen in the study group by the time of discharge, although the difference between the groups was not statistically significant (17.0 ⫾ 6.4 mL in the ELTGOL group vs 10.2 ⫾ 9.7 mL in the control group, P = 0.076). The length of hospitalization of each group was similar (9.5 ⫾ 3.2 days in the ELTGOL group, 10.0 ⫾ 2.4 in the control group, P = 0.530). At discharge, the two groups showed a similar degree of improvement, although there was a reduction in dyspnoea as measured by the Borg score in the ELTGOL group (Fig. 2, P = 0.004); differences were small. One month after hospital discharge, the health status perception as measured by St George Respiratory Questionnaire, was similar in both groups © 2009 The Authors Journal compilation © 2009 Asian Pacific Society of Respirology


ELTGOL in COPD exacerbations

(54.9 ⫾ 17.3 in the ELTGOL group, 57.2 ⫾ 19.8 in the control group, P = 0.775).

the need for hospitalization (95% CI: 0.46–14.80; P = 0.2776) (Fig. 3). No information was available as to whether patients continued to use the ELTGOL technique after the study.

Results of long-term follow up The study population at follow up is described in Figure 1. Eleven patients from each group were available for analysis 6 months post hospital discharge. Patients lost to follow up were contacted where possible. Reasons for non-attendance included: transport limitations (cost or no car), lack of subjective improvement and no active physiotherapy treatment (the control group mentioned this more frequently). At 6 months post hospital discharge, COPD exacerbations were similar (2.8 ⫾ 3.0 vs 3.4 ⫾ 1.7, P = 0.414), and the number of hospitalizations did not differ between the two groups (1.9 ⫾ 2.5 vs 1.5 ⫾ 1.6, respectively, P = 0.945) The time to event curve shows a non-significant reduction in both the number of exacerbations in the ELTGOL group (95% CI: 0.55–10.12; P = 0.2444) and

10 9 8 7 6 5 4 3 2 1 0

ELTGOL group Control group

Borg score at admission

Borg score at discharge

Figure 2 Comparisons between Borg score at admission and at discharge, showing significant improvement in the intervention group at discharge.

Figure 3

DISCUSSION The present study failed to show a clear advantage of chest physiotherapy using ELTGOL in patients with an acute exacerbation of moderate to severe COPD. Although limited by the small sample size, this study appears to be one of only few randomized studies comparing ELTGOL, as adjuvant treatment in patients with acute exacerbation of COPD, to conventional treatment. ELTGOL is an easily performed technique which is well tolerated by patients. It is known to help mucus clearance. Nevertheless, its definitive role in COPD exacerbations is not proven, perhaps due to the considerable variability of sputum produced by these patients. In patients characterized by sputum hyperproduction (more than 25 mL/day), there was no statistically significant evidence of benefit after the period of treatment, although a reduction in sputum volume was evident. At present, there is no preferred airway clearance technique for different groups of patients; however, it has been suggested that airway clearance techniques should be applied to patients who expectorate more than 25–30 mL daily or, if they cannot expectorate, who have clear signs of mucus retention.11,12 In this study, patients treated with ELTGOL experienced substantial symptomatic relief with reduced perception of dyspnoea after the treatment. On the other hand, more specific parameters of well-being, like health-related questionnaires, did not show greater benefit in patients treated with ELTGOL; so it may be that the reduction in dyspnoea reflected in the Borg score was not associated with the amount of sputum and could not be explained by specific questions addressed in the questionnaires about QoL. It may also be argued that the lack of evidence

Survival curve (time-to-event) analysis for exacerbation (a) and hospitalization (b) for the two groups.

© 2009 The Authors Journal compilation © 2009 Asian Pacific Society of Respirology

Respirology (2009) 14, 424–428

428 of improvement was attributable to the relatively mild degree of exacerbation, even in quite severe COPD; patients had moderate hypoxaemia without hypercarbia. The small number of patients followed to 6 months limits the long-term assessment of exacerbations and hospitalization rate. The population which returned for follow up may not be representative of the initial study population. In addition, the small number of patients may have resulted in a type 2 error and may thus underestimate the benefits of physiotherapy. COPD is characterized by recurrent exacerbations that lead to progressive worsening of symptoms and have a variable, but considerable impact on a patient’s QoL,13,14 as well as an important social and economic burden. Rehabilitation is mostly performed during the stable phase of COPD and is mainly targeted at muscle retraining and clearance of secretions; in particular, bronchial drainage is aimed at reducing bronchial obstruction, improving ventilation of pulmonary zones affected by microatelectasis and preventing infections. Meta-analyses, reviews and studies have been undertaken on airway clearance techniques,5–10,15 but the lack of standardization and vague definitions make comparisons very complicated and sometimes misleading, thus failing to demonstrate their benefit. The American Thoracic Society guidelines for the treatment of COPD in 1995 recommended the use of respiratory physiotherapy in hypersecretive patients.14 However, the subsequent guidelines (GOLD 2001) did not confirm such recommendations.8 Thus, due to a lack of studies supporting the use of respiratory physiotherapy in COPD, its use depends on the preference of each centre. Concerns have been raised about inappropriate indications for physiotherapy, resulting in an increase of health-related costs without providing any advantages, such as reduction of the length of hospitalization and mortality.15 In conclusion, chest physiotherapy using the ELTGOL technique appears to have a limited role in patients with exacerbation of moderate to severe COPD.

Respirology (2009) 14, 424–428

M Kodric et al.

REFERENCES 1 Seemungal TA, Donaldson GC, Bhowmik A, Jeffries DJ, Wedzicha JA. Time course and recovery of exacerbations in patients with chronic obstructive pulmonary disease. Am. J. Respir. Crit. Care Med. 2000; 161: 1608–13. 2 Troosters T, Casaburi R, Gosselink R, Decramer M. Pulmonary rehabilitation in chronic obstructive pulmonary disease. Am. J. Respir. Crit. Care Med. 2005; 172: 19–38. 3 Ciesla ND. Chest physical therapy for patients in the intensive care unit. Phys. Ther. 1996; 76: 609–25. 4 Singh S. Physiotherapy in stable COPD. Chron. Resp. Dis. 2005; 2: 57–8. 5 Jones AP, Rowe BH. Bronchopulmonary hygiene physical therapy for chronic obstructive pulmonary disease and bronchiectasis. Cochrane Database Syst. Rev. 2000; 2: CD000045. 6 Holland AE, Button BM. Is there a role for airway clearance techniques in chronic obstructive pulmonary disease? Chron. Resp. Dis. 2006; 32: 83–91. 7 Postiaux G, Lens E, Alsteens G. L’expiration lente totale glotte ouverte en decubitus lateral (ELTGOL): nouvelle manoeuvre pour la toilette bronchique objectivee par videobronchographie. [Slow expiration in lateral decubitus with the glottis totally open (ELTGOL): a new manoeuvre for bronchial clearance visualized by videobronchography.] Ann. Kinesither. 1987; 14: 341–50. 8 Global initiative for Chronic Obstructive Lung Disease. Global Strategy for Diagnosis, Management and Prevention of Chronic Obstructive Pulmonary Disease. National Institutes of Health, National Heart, Lung and Blood Insitute, Bethesda, 2001. 9 Anthonisen NR, Manfreda J, Warren CP, Hershfield ES, Harding GK et al. Antibiotic therapy in exacerbations of chronic obstructive pulmonary disease. Ann. Intern. Med. 1987; 106: 196–204. 10 Carone M, Bertolotti G, Anchisi F, Spagnolatti L, Zotti AM et al. Il St. George’s Respiratory questionnaire (SGRQ): la versione italiana. Rass. Pat. App. Resp. 1999; 14: 31–7. 11 Kim CS, Iglesias AJ, Sackner MA. Mucus clearance by two-phase gas-liquid flow mechanism: asymmetric periodic flow model. J. Appl. Physiol. 1987; 62: 959–71. 12 Spencer S, Calverley PM, Burge PS, Jones PW. Impact of preventing exacerbations on deterioration of health status in COPD. Eur. Respir. J. 2004; 23: 698–702. 13 Lacasse Y, Brosseau L, Milne S, Martin S, Wong E et al. Pulmonary rehabilitation for chronic obstructive pulmonary disease. Cochrane Database Syst. Rev. 2002; 3: CD003793. 14 ATS Standard for the diagnosis and care of patients with chronic obstructive pulmonary disease. Am. J. Respir. Crit. Care Med. 1995; 152: s77–s120. 15 Alexander C, Weingarten S, Mohsenifar Z. Clinical strategies to reduce utilization of chest physiotherapy without compromising patient care. Chest 1996; 110: 432–4.

© 2009 The Authors Journal compilation © 2009 Asian Pacific Society of Respirology

ELTGOL - Wiley Online Library

ABSTRACT. Background and objective: Exacerbations of COPD are often characterized by increased mucus production that is difficult to treat and worsens patients' outcome. This study evaluated the efficacy of a chest physio- therapy technique (expiration with the glottis open in the lateral posture, ELTGOL) during acute ...

186KB Sizes 0 Downloads 624 Views

Recommend Documents

poly(styrene - Wiley Online Library
Dec 27, 2007 - (4VP) but immiscible with PS4VP-30 (where the number following the hyphen refers to the percentage 4VP in the polymer) and PSMA-20 (where the number following the hyphen refers to the percentage methacrylic acid in the polymer) over th

Recurvirostra avosetta - Wiley Online Library
broodrearing capacity. Proceedings of the Royal Society B: Biological. Sciences, 263, 1719–1724. Hills, S. (1983) Incubation capacity as a limiting factor of shorebird clutch size. MS thesis, University of Washington, Seattle, Washington. Hötker,

Kitaev Transformation - Wiley Online Library
Jul 1, 2015 - Quantum chemistry is an important area of application for quantum computation. In particular, quantum algorithms applied to the electronic ...

PDF(3102K) - Wiley Online Library
Rutgers University. 1. Perceptual Knowledge. Imagine yourself sitting on your front porch, sipping your morning coffee and admiring the scene before you.

Standard PDF - Wiley Online Library
This article is protected by copyright. All rights reserved. Received Date : 05-Apr-2016. Revised Date : 03-Aug-2016. Accepted Date : 29-Aug-2016. Article type ...

Authentic inquiry - Wiley Online Library
By authentic inquiry, we mean the activities that scientists engage in while conduct- ing their research (Dunbar, 1995; Latour & Woolgar, 1986). Chinn and Malhotra present an analysis of key features of authentic inquiry, and show that most of these

the characteristics of subscribers and raises advertisers' willingness to ... IN THIS PAPER I INVESTIGATE WHETHER MEDIA TARGETING can raise the value of.

Verbal Report - Wiley Online Library
Nyhus, S. E. (1994). Attitudes of non-native speakers of English toward the use of verbal report to elicit their reading comprehension strategies. Unpublished Plan B Paper, Department of English as a Second Language, University of Minnesota, Minneapo

PDF(270K) - Wiley Online Library
tested using 1000 permutations, and F-statistics (FCT for microsatellites and ... letting the program determine the best-supported combina- tion without any a ...

Phylogenetic Systematics - Wiley Online Library
American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024. Accepted June 1, 2000. De Queiroz and Gauthier, in a serial paper, argue that state of biological taxonomy—arguing that the unan- nointed harbor “wide

PDF(270K) - Wiley Online Library
ducted using the Web of Science (Thomson Reuters), with ... to ensure that sites throughout the ranges of both species were represented (see Table S1). As the ...

Standard PDF - Wiley Online Library
Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN 37996, USA,. 3Department of Forestry and Natural. Resources, Purdue University ...

PDF(118K) - Wiley Online Library
“legitimacy and rationality” of a political system results from “the free and ... of greater practical import and moral legitimacy than other models of democracy.

Strategies for online communities - Wiley Online Library
Nov 10, 2008 - This study examines the participation of firms in online communities as a means to enhance demand for their products. We begin with theoretical arguments and then develop a simulation model to illustrate how demand evolves as a functio

Understanding dynamic capabilities - Wiley Online Library
Defining ordinary or 'zero-level' capabilities as those that permit a firm to ... reliance on dynamic capability, by means here termed 'ad hoc problem solving.

Rockets and feathers: Understanding ... - Wiley Online Library
been much progress in terms of theoretical explanations for this widespread ... explains how an asymmetric response of prices to costs can arise in highly ...

The knowledge economy: emerging ... - Wiley Online Library
explain the microfoundations and market mechanisms that underpin organizational disaggregation and the communal gover- nance forms observed in the knowledge economy. Because of the increasingly cen- tral role of HR professionals in knowledge manageme

XIIntention and the Self - Wiley Online Library
May 9, 2011 - The former result is a potential basis for a Butlerian circularity objection to. Lockean theories of personal identity. The latter result undercuts a prom- inent Lockean reply to 'the thinking animal' objection which has recently suppla

The Metaphysics of Emergence - Wiley Online Library
University College London and Budapest University of. Technology and Economics. I. Mental Causation: The Current State of Play. The following framework of ...

Competing paradigms of Amazonian ... - Wiley Online Library
September 2014, immediately after the accepted version of this manuscript was sent to the authors on 18 September. 2014. doi:10.1111/jbi.12448. Competing ..... species are there on earth and in the ocean? PLoS Biology, 9, e1001127. Moritz, C., Patton

Allergic contact dermatitis - Wiley Online Library
Mar 18, 2013 - affected in particular by the experience and individual factors of the examiner. There- fore, a high degree of standardization and continuous ...