Matches in SemOpenAlex for { <https://semopenalex.org/work/W2137762272> ?p ?o ?g. }
- W2137762272 endingPage "365" @default.
- W2137762272 startingPage "347" @default.
- W2137762272 abstract "INTRODUCTION The Olympic Games is the largest sport event in the world. In Beijing, 10,500 athletes competed, selected from a large group of elite athletes in 204 countries. Sports participation on the elite level, aside from winning medals, fame and other rewards, is also important from a health perspective. There is no longer any doubt that regular physical activity reduces the risk of premature mortality in general, and of coronary heart disease, hypertension, colon cancer, obesity, and diabetes mellitus in particular. The question is whether the health benefits of sports participation outweigh the risk of injury and long-term disability, especially in high-level athletes.1 have studied the incidence of chronic disease and life expectancy of former male world-class athletes from Finland in endurance sports, power sports and team sports. The overall life expectancy was longer in the high-level athlete compared to a reference group (75.6 vs 69.9 years). The same group also showed that the rate of hospitalization later in life was lower for endurance sports and power sports compared to the reference group.2 This resulted from a lower rate of hospital care for heart disease, respiratory disease and cancer. However, the athletes were more likely to have been hospitalized for musculoskeletal disorders. Thus, the evidence suggests that although there is a general health benefit from sports participation, injuries represent a significant side effect. One priority of the International Olympic Committee (IOC) is to protect the health of the athlete. During recent years, prevention of injuries and illnesses has been high on the IOC agenda. During the Athens Games an injury surveillance system was applied for all team sports.3 During the Beijing Games, the IOC ran, for the first time, an injury surveillance system covering all the athletes, showing a 10% incidence of injuries.4 In Vancouver and London the surveillance system will include disease conditions as well. The surveillance studies are prerequisites for providing evidence for health development in sports as well as for developing prevention programs. Another method to decrease injuries and diseases in the elite athlete is to perform a pre-participation examination (PPE) or periodic health evaluation (PHE) of all elite athletes.5 PHE in various forms have been available for many years, but a recent analyses5 has questioned the efficacy of PHEs in detecting serious problems in the elite athlete. In March 2009, the IOC assembled an expert group to discuss the current state of health evaluations for athletes, aiming to provide recommendations for a practical PHE for the elite athlete, as well as to outline the need for further research. The task of the group was to review the benefits as well as potential negative effects of PHE at the elite sport level. The group did not take any position as to whether PHE should be recommended as compulsory for participation in sport. That is for the relevant sports authorities to decide. The PHE can serve many purposes. It includes a comprehensive assessment of the athlete's current health status and risk of future injury or disease and, typically, is the entry point for medical care of the athlete. The PHE also serves as a tool for continuous health monitoring in athletes. Recent advances in this field relate to: (1) data on sudden cardiac death and other noncardiac medical problems, and the detection of risk factors and groups; (2) a consensus conference on concussion; (3) data on eating disorders; and (4) data on risk factors for musculoskeletal injuries. This paper addresses each of these advances in more detail after a discussion on the purpose of a PHE and the evidence we have supporting the different components of the PHE. PURPOSES OF THE MEDICAL EVALUATION In a narrow sense, the main purpose of the PHE is to screen for injuries or medical conditions that may place an athlete at risk for safe participation. Athletes may be affected by conditions that do not have overt symptoms and that can only be detected by periodic health evaluations. One example is cardiovascular abnormalities, such as hypertrophic cardiomyopathy, arrythmogenic right ventricular cardiomyopathy or congenital coronary arteries anomalies. These are typically silent until a potentially fatal arrhythmia occurs, but may in some cases be detected through a careful cardiovascular examination. Screening is a strategy used in a population to detect a disease in individuals without signs or symptoms of that disease. The intention is to identify pathologic conditions early, thus enabling earlier intervention and management in the hope of reducing future morbidity and mortality. Although screening may lead to an earlier diagnosis, not all screening programs have been shown to benefit the person being screened. To ensure that screening programs confer the intended benefit, the World Health Organisation published what have become known as the Wilson-Jungner criteria for appraising a screening programme.6 The main criteria are that the condition being screened for is an important health problem (depends not just on how serious the condition is, but also how common it is), that there is a detectable early stage, that treatment at an early stage is of more benefit than at a later stage and that a suitable test is available to detect disease in the early stage. From a public health perspective, there is insufficient evidence to date to mandate any specific screening tests for elite athletes apart from those recommended for the general population. This is mainly the consequence of the low risk of serious conditions in this population. An important limitation is also the lack of suitable screening tests; such tests must be reliable (repeatable, good inter-observer agreement), sensitive (detects all those with increased risk), specific (detects only those with increased risk), affordable (ideally cheap, easy to perform, widely available), acceptable to the screening population and subject to quality assurance. However, the PHE may serve other purposes than just screening athletes for future health problems. One obvious goal is to ensure that current health problems are managed appropriately and, ultimately, to determine whether an athlete is medically suitable to engage in a particular sport or event. Even elite athletes with easy access to medical care do not always seek medical attention for injuries or disease, despite having significant symptoms. Some silent conditions are common and, although not severe from a health perspective, may influence sports performance. An example of this is mild iron deficiency, which is common in female athletes. Periodic health evaluations and ongoing monitoring represent an opportunity to diagnose and manage such conditions. They also provide an opportunity to identify conditions that are barriers to performance. An example is astigmatism, which can be detected on a simple test of visual acuity. Another important function of PHEs is that they allow the athlete an opportunity to establish a relationship with the health personnel who will be involved in providing continuing care. Finally, the PHE also represents an opportunity to look for characteristics which may put the elite athlete at risk for future injury or disease. However, as mentioned above, there is limited direct evidence to suggest that it is possible to predict future outcomes based on the PHE. Nevertheless, there is evidence in some areas, such as injury risk factor assessment,7 that holds future promise and warrants investigation related to the PHE. Depending on the sport and the age, ethnic origin and gender of the athlete, it may be prudent to include an assessment of specific risk factors in the PHE. GENERAL REQUIREMENTS OF A PHE It is important to address and balance the ethical and legal aspects of the PHE in order to help protect the rights and responsibilities of athletes, physicians, sporting organizations and other persons concerned. In the context of designing and implementing a PHE, the following considerations need to be taken into account: PHE should be based on sound scientific and medical criteria PHE should be performed in the primary interest of the athlete, that is, assessing his/her health in relation to his/her practice of a given sport PHE should be performed under the responsibility of a physician trained in sports medicine, preferably by the physician responsible for providing ongoing medical care for the athlete, for example, the team physician The decision concerning the nature and scope of the PHE should take into account individual factors, such as the geographical region, the sport discipline, the level of competition, age and gender of the athlete The setting of the evaluation should be chosen to optimize the accuracy of the examination and respect the privacy of the athlete. The PHE should preferably be carried out in the physician's office, which assures privacy, access to prior medical records, and an appropriate patient-physician relationship A physician can only perform a PHE with the free and informed consent of the athlete and, if applicable, his/her legal guardian If PHE evidences that an athlete is at serious medical risk, the physician must strongly discourage the athlete from continuing training or competing until the necessary medical measures have been taken Based on such advice, it is the responsibility of the athlete to decide whether to continue training or competing If a physician is requested to issue a medical certificate, he or she must have explained in advance to the athlete the reason for the PHE and its outcome, as well as the nature of information provided to the third parties. In principle, the medical certificate may only indicate the athlete's fitness or unfitness to participate in training or competition and should minimize disclosure of confidential medical information In many settings, the PHE is used to offer medical clearance to participate in sport and is seen as a 1-time certification for future involvement in elite sport. However, the evaluation of the athlete's health should ideally be seen as a dynamic, ongoing process. While many aspects of the PHE will be common to all elite athletes, it should be tailored to be gender, age, race, culture and sport specific when appropriate. If any injury or medical condition is identified, it should be managed in a manner consistent with the existing standards of medical care. If warranted, this may involve referral to the appropriate specialists for further evaluation and management. It should be noted that the PHE is also the time that medications or nutritional products in use or prescribed should be reviewed to determine if a Therapeutic Use Exemption (TUE) application to the World Anti-Doping Association (WADA) is needed. The timing of the PHE should ideally allow for sufficient time for management of any injuries or medical problems well before major competitions. For example, it is preferable to conduct a PHE during the off-season so that rehabilitation or other treatment can restore the athlete to optimal health before facing maximal physical stress. As the PHE is the only contact that many elite athletes will have with medical personnel, it should be seen as an opportunity for education regarding other health risks and health-related behavior. The following document is laid out in sections that correspond to the various areas of evaluation appropriate to the elite athlete. 1. CARDIOLOGY 1.1 Introduction The scope of the cardiovascular PHE is to detect potentially lethal cardiovascular disease in elite athletes and start appropriate management to reduce the risk for sudden cardiac death and/or disease progression in a timely fashion. 1.2 Evidence Base 1.2.1 Cardiovascular (CV) Risk of Competitive Sport Participation Regular participation in training and athletic competition is associated with an increased risk for sudden cardiac death (SCD), with an average relative risk for athletes of 2.8 times compared to their nonathletic counterpart.8 It is worthy to note, however, that sport is not per se the cause for greater incidence of SCD. It is the combination of intensive physical exercise in athletes with underlying cardiovascular disease, which can trigger ominous arrhythmias leading to cardiac arrest. The relative risk of sport participation is different according to the underlying disease, and it is greatest in case of cardiomyopathies (such as hypertrophic cardiomyopathy or arrhythmogenic right ventricular cardiomyopathy) or congenital coronary arteries anomalies.8 1.2.2 Rationale for CV Evaluation in Elite Competitive Athletes The vast majority of the athletes dying suddenly do not experience premonitory symptoms9; therefore, the PHE represents the only strategy capable to identify athletes with silent cardiac disease, and allow appropriate management to reduce the risk of SCD and disease progression. Identifying asymptomatic athletes with underlying cardiovascular disease through the PHE is important because SCD could be prevented by lifestyle modification, including (when necessary) restriction from competitive sports activity, but also prophylactic treatment by drugs, implantable cardioverter defibrillator (ICD) or other therapeutic options. Athletes carrying an increased cardiac risk may have a favourable long-term outcome thanks to timely identification and appropriate clinical management.10 1.2.3 Rationale for Including the 12-Lead Electrocardiogram (ECG) in the PHE Recent scientific evidence supports the role of ECG in reducing mortality in screened athletes.11 This concept is based on the recognition that ECG is abnormal in most individuals with hypertrophic cardiomyopathy (up to 90%) and arrhythmogenic right ventricular cardiomyopathy (up to 80%). The ECG can also identify athletes with Wolff-Parkinson-White syndrome and ion channel diseases, such as Lènegre conduction disease, long or short QT syndromes, and Brugada syndrome,12,13 However, there has been criticism voiced related to available data on the use of ECG in the elite athlete based on lack of an unscreened athletic control group. A comparison of athletes screened with ECG versus athletes non-screened will require 2 matched large athlete populations (several thousand athletes, in consideration of the low incidence of cardiomyopathies) undergoing long-term follow-up (at least 2 decades, due to the young age of athletes at initial evaluation). It has been demonstrated that adding a 12-lead ECG examination to history and physical examination results in a substantial increase in the ability to identify potentially lethal heart disorders12,13 and this strategy has been endorsed in “The Lausanne Recommendations”14 and the European Society of Cardiology recommendations.15 However, it is not currently recommended by the American Heart Association.16,17 1.3 Proposal for PHE The following questions regarding cardiovascular abnormalities should be included: 1.3.1 Family History Family history of 1 or more relatives with disability or death of heart disease (sudden/unexpected) before age 50 Family history of cardiomyopathy, coronary artery disease, Marfan syndrome, long QT syndrome, severe arrhythmias, or other disabling cardiovascular disease 1.3.2 Personal History Syncope or near-syncope Exertional chest pain or discomfort Shortness of breath or fatigue out of proportion to the degree of physical effort Palpitations or irregular heartbeat Physical examination should be performed according to the best clinical care and should investigate the presence of: Musculoskeletal and ocular features suggestive of Marfan syndrome Diminished and delayed femoral artery pulses Mid- or end-systolic clicks Abnormal second heart sound (single or widely split and fixed with respiration) Heart murmurs (systolic grade >2/6 and any diastolic) Irregular heart rhythm Brachial, bilateral blood pressure >140/90 mm Hg on more than 1 reading 1.3.3 The 12-Lead ECG The 12-lead ECG should be recorded on a non-training day, during rest, according to best clinical practice. Interpretation of the ECG abnormalities can be categorized according to the criteria defined by Corrado et al18 into 2 groups: (1) the most common in trained athletes (sinus bradycardia, first degree AV block, notched QRS in V1 or incomplete right bundle branch block, isolated QRS voltage criteria for LV hypertrophy) consistent with athlete's age, ethnical origin and level of athletic conditioning, and that do not require additional testing; (2) all other less common ECG abnormalities should be further evaluated to exclude cardiovascular disease (Figure 1).FIGURE 1: Twelve lead ECG abnormalities.1.3.4 Further Investigations At present, there is no agreement regarding the need for routine use of echocardiography in the PHE. Neither is there a role for routine use of other imaging or invasive testing. However, in the presence of abnormal findings either at history, physical examination or 12-lead ECG, additional testing should be performed in order to confirm (or exclude) cardiovascular disease. In most instances, echocardiography is the first-line test, but other imaging modalities (such as cardiac magnetic resonance) or invasive testing, when necessary, may be pursued. In adult athletes (> 35 years) exercise ECG testing in the context of PHE is efficient to detect otherwise unsuspected cardiac abnormalities19 and is currently recommended for elite athletes with increased cardiovascular risk profile.20 1.4 Management of Athletes with CV Abnormalities The IOC PHE Consensus Group recommends that any athlete identified with a CV abnormality should be managed according to the current, widely accepted clinical recommendations, that is, Bethesda Conference #36 and ESC recommendations15,21,22. The group acknowledges that identification of cardiac disease in an athlete represents a challenging question regarding the ethical, medical and legal consequence with particular regard to the need for disqualification from competition. However, there is scientific evidence that preventing athletes with specific cardiovascular abnormality from regular training and competition is an efficient strategy for preventing SCD.10,23 Unnecessary exclusion from participation of competitive athletes with non-lethal diseases is a problem. Therefore, there is a need for a common agreement of sports eligibility guidelines and management of competitive athletes with cardiovascular diseases in the future.24 The main goal should be to reduce the number of unnecessary disqualifications and to adapt (rather than restrict) sports activity in relation to the specific cardiovascular risk. Finally, we recognize that young competitive athletes (<18 years) require specific expertise in the evaluation, interpretation of findings and management. 1.5 Educational Programmes The sport organizations together with scientific sport societies should encourage and support educational activities intended to enhance the knowledge and skill of physicians involved in the cardiology part of the PHE process. 1.6 Research Although there are issues of debate regarding wide-scale mandatory use of the ECG for athlete screening16,24, there is sufficient evidence to justify a staged implementation with evaluation to assess the properties of the test (sensitivity, specificity, predictive value) in a variety of sporting populations. Staged implementation would provide a natural control group to measure differences in outcome between ECG screened and unscreened groups. Finally, the mortality effects of a screening program documented in Italy need to be replicated in other ethnic populations where the underlying disease conditions may differ from those seen in Italy. The sport organizations and scientific sport societies should encourage research that could expand our current knowledge and data base regarding the mechanisms and strategies to prevent SCD in competitive athletes. 2. NON-CARDIAC MEDICAL CONDITIONS 2.1 Introduction To date, the main elements of the PHE have been to screen elite athletes for possible risk for sudden cardiovascular death,15,25 musculoskeletal injury,26 and head injury.27 Furthermore, elements of the PHE that focus on non-cardiac medical conditions have to date been confined to hematological conditions,28 lung disease, particularly exercise-induced bronchoconstriction,29 and specific medical concerns of the female athlete.30 However, sports physicians who regularly perform medical assessments on elite athletes, as well as members of the medical team that accompany athletes to the Olympic Games and other international sports events, commonly encounter medical conditions that are non-injury related, and are of a non-cardiac nature.31-33 In one study, it was reported that 50% of the 1804 athletes seen at the multipurpose medical facility at the 1996 Olympic Games were treated for non-injury related illnesses.34 In another study conducted in the athlete medical clinic during the 2002 Winter Olympic Games, medical diagnoses, notably respiratory conditions, were more commonly reported than traumatic conditions.33 Furthermore, in 2 other studies, over 50% of the medical consultations in a participating team during 2 Olympic Games were non-injury related.31,32 It is important to note that the frequency of cardiac-related medical consultations reported in these 2 studies was very low.31,32 Therefore, medical conditions in systems other than the cardiovascular system are very common in elite athletes. These conditions can occur immediately before competitions, during periods of training in preparation for competitions, and after competitions. In 2 reports, the frequency of medical conditions reported in athletes during the Olympic Games has been documented (Table 1). These data indicate that medical conditions, other than cardiovascular conditions, are common in elite athletes, yet these conditions have not received much attention in a PHE. A spectrum of medical conditions can occur in athletes across a number of medical systems (Table 2) and these can be identified during a PHE.35,36 Finally, a number of these conditions are transient and can be treated. Therefore, clearance for sports participation when athletes suffer from these conditions is an ongoing process and requires ongoing monitoring and assessment.TABLE 1: Frequency (% of all Formal Medical Consultations) of Medical Consultations at the Olympic Games in a TeamTABLE 2: Noncardiac Systems That Should be Considered in a PHEThe purpose of this section is to (1) briefly review the evidence base for including elements in the PHE that focus on non-cardiac medical conditions; (2) recommend elements in the medical history, physical examination and special investigations that could be included in a PHE to identify significant non-cardiac medical conditions; and (3) suggest future directions for research in this area. 2.2 Evidence Base: Non-Cardiac Medical Conditions There is very little data available on the inclusion of assessment for non-cardiac medical conditions in a PHE. Evidence for the inclusion of screening tests to identify non-cardiac medical conditions in a PHE is therefore largely limited to expert opinion and case series. However, the identification of some non-cardiac medical conditions is frequently included in the medical history, physical examination and profile of special investigations of existing PHE recommendations.37-42 The evidence base for including screening to identify non-cardiac medical conditions in a PPE will be briefly reviewed below. 2.2.1 Pulmonary System The rationale for including an assessment of the pulmonary system in a PHE is that respiratory symptoms that are suggestive of asthma are common in athletes.43 At the time of a PHE, these symptoms can be identified, and the clinical examination, together with objective special tests can be used to confirm the diagnosis of asthma.43 The prevalence of asthma in athletes is high and varies from 3%-23% in summer sports to 12%-50% in winter sports.44,45 Furthermore, during a PHE, respiratory tract conditions other than asthma that can also give rise to respiratory symptoms in athletes can be identified.45 2.2.2 Hematological The main rationale for including routine hematological assessment during a PHE is based on the higher than expected prevalence of decreased iron stores in athletes, particularly female athletes.28,46-51 An additional rationale is to determine if the athlete has anemia (iron deficiency or other), and to identify other illnesses such as infections.28 It is noteworthy that hematological testing has been suggested as a screening/monitoring tool for blood doping (hematological passport) as well.52 The likelihood of a positive result on routine hematological screening is higher in physically active females compared with male athletes.28,48,53 2.2.3 Allergies The rationale for including assessments in the PHE to identify allergies, particularly allergic rhinoconjunctivitis, in elite athletes is based on the fact that (1) significantly higher than expected prevalence of allergic conditions has been observed in elite athletes54-57; (2) travelling athletes could be exposed to a variety of allergens at different venues where international competitions take place55; and (3) acute and chronic allergies could result in morbidity and also reduce athletic performance.58 2.2.4 Infections and Immunological The rationale to consider infective disease in a PHE is based on a number of important considerations. Firstly, it is established that during intense training and immediately following competitions, there is evidence of immune suppression in athletes that could predispose them to infective disease.59,60 Secondly, acute systemic infective illness is a contra-indication to participation in sports because of the risk of viral myocarditis, organ injury (splenomegaly) and in some cases increased risk of transmission of the infective illness to fellow athletes.61-63 Thirdly, the PHE provides an opportunity to assess whether an athlete has been immunized against infective conditions, including those that may be associated with international travel to specific regions. There are a number of infective illnesses that could be considered when performing a PHE and these have been reviewed recently.61,62 2.2.5 Ear, Nose and Throat (ENT) The rationale for including the ear, nose and throat (ENT) assessment in a PHE is based on the high incidence medical consultations during international competitions that are related to this system in elite athletes (Table 1). Furthermore, the common illnesses encountered in the ENT system of athletes are allergies54,58 and upper respiratory tract infections.33,60,61,64 The basis for including this spectrum of conditions in PHE has already been discussed. 2.2.6 Dermatological The rationale for including a dermatological assessment in the PHE is that skin disorders are very common in athletes.65-67 Furthermore, participation in sports may predispose athletes to certain skin conditions and there is a risk of transmission of certain skin conditions during sports.65 Therefore, clearance to compete may have to be withheld temporarily if athletes suffer from some skin infections.65 2.2.7 Urological The rationale for including an assessment of the urological system in the PHE is not based on strong evidence. However, it is known that (1) renal and bladder disease can be asymptomatic; and (2) conditions such as asymptomatic haematuria, proteinuria and pyuria are often encountered when screening in athletes is conducted.68 Although these conditions may not be clinically significant, they do however require further evaluation to exclude underlying urological disease. 2.2.8 Gastrointestinal (GIT) The rationale for including an assessment of the gastro-intestinal (GIT) system in the PHE is that GIT symptoms are very common in athletes (particularly endurance athletes) during sports participation.69 Exclusion of significant underlying GIT disease is therefore important in athletes, particularly those that regularly suffer from GIT symptoms during exercise.69 Furthermore, GIT conditions are also frequently encountered when travelling with athletes to international competitions.31,32 2.2.9 Nervous System (Neurological) The rationale for including assessment of neurological conditions in the PHE of athletes is that neurological conditions are common70 and can include a variety of different conditions such as headaches and epilepsy. Furthermore, although uncommon, stroke can occur in younger adults, including athletes. It has been suggested that the PHE should include screening for the risk factors of stroke in young athletes.70 2.2.10 Endocrine/Metabolic The rationale for routine enquiry to determine if elite athletes have underlying endocrine and metabolic disease is (1) that these conditions do occur in elite athletes; (2) one of the more common endocrine conditions in elite athletes is diabetes mellitus - 9 Olympic athletes required therapeutic use exemption for the use of insulin in the 2004 Summer Olympic Games71; and (3) elite athletes with existing endocrine and metabolic disease may require counseling and advice because medication they may use could contravene doping control regulations.72 2.2.11 Ophthalmology The principle rationale for including ophthalmological assessment in the PHE is that ophthalmic conditions, particularly reduced visual acuity, have been reported in 4.5%-25% of college athletes undergoing a PHE.35,36,73 Other less common ophthalmological conditions can also be identified. 2.3 Proposal for Content of the PHE Assessment of non-cardiac medical conditions during a PHE would include an appropriate systematic medical history (Table 3). A directed physical examination and selected special investigations (Table 4) should follow. Routine investigations th" @default.
- W2137762272 created "2016-06-24" @default.
- W2137762272 creator A5000583840 @default.
- W2137762272 creator A5000933955 @default.
- W2137762272 creator A5007196302 @default.
- W2137762272 creator A5009422570 @default.
- W2137762272 creator A5010641751 @default.
- W2137762272 creator A5012665428 @default.
- W2137762272 creator A5029419425 @default.
- W2137762272 creator A5040032065 @default.
- W2137762272 creator A5040308637 @default.
- W2137762272 creator A5042570450 @default.
- W2137762272 creator A5046080203 @default.
- W2137762272 creator A5051648643 @default.
- W2137762272 creator A5053030261 @default.
- W2137762272 creator A5054539059 @default.
- W2137762272 creator A5063587048 @default.
- W2137762272 creator A5065731258 @default.
- W2137762272 creator A5073580058 @default.
- W2137762272 creator A5075700251 @default.
- W2137762272 creator A5082992074 @default.
- W2137762272 date "2009-09-01" @default.
- W2137762272 modified "2023-10-18" @default.
- W2137762272 title "The International Olympic Committee (IOC) Consensus Statement on Periodic Health Evaluation of Elite Athletes, March 2009" @default.
- W2137762272 cites W114486132 @default.
- W2137762272 cites W1504287332 @default.
- W2137762272 cites W1567965111 @default.
- W2137762272 cites W1578175168 @default.
- W2137762272 cites W1602374720 @default.
- W2137762272 cites W1845603411 @default.
- W2137762272 cites W1852185365 @default.
- W2137762272 cites W1965558091 @default.
- W2137762272 cites W1968683269 @default.
- W2137762272 cites W1971591524 @default.
- W2137762272 cites W1974229478 @default.
- W2137762272 cites W1978750038 @default.
- W2137762272 cites W1979362120 @default.
- W2137762272 cites W1980693096 @default.
- W2137762272 cites W1981416187 @default.
- W2137762272 cites W1983247815 @default.
- W2137762272 cites W1985141762 @default.
- W2137762272 cites W1990514899 @default.
- W2137762272 cites W1991452514 @default.
- W2137762272 cites W1992386406 @default.
- W2137762272 cites W1992907868 @default.
- W2137762272 cites W1993154081 @default.
- W2137762272 cites W1993793339 @default.
- W2137762272 cites W1993945850 @default.
- W2137762272 cites W1997930812 @default.
- W2137762272 cites W1999660116 @default.
- W2137762272 cites W2000288116 @default.
- W2137762272 cites W2003030231 @default.
- W2137762272 cites W2006038796 @default.
- W2137762272 cites W2012964264 @default.
- W2137762272 cites W2016841155 @default.
- W2137762272 cites W2018606017 @default.
- W2137762272 cites W2018839072 @default.
- W2137762272 cites W2020530051 @default.
- W2137762272 cites W2023516017 @default.
- W2137762272 cites W2023903897 @default.
- W2137762272 cites W2024214116 @default.
- W2137762272 cites W2024614249 @default.
- W2137762272 cites W2027533961 @default.
- W2137762272 cites W2029654563 @default.
- W2137762272 cites W2033388805 @default.
- W2137762272 cites W2034004262 @default.
- W2137762272 cites W2036155165 @default.
- W2137762272 cites W2037002370 @default.
- W2137762272 cites W2039345452 @default.
- W2137762272 cites W2042902068 @default.
- W2137762272 cites W2045508196 @default.
- W2137762272 cites W2046036256 @default.
- W2137762272 cites W2048205181 @default.
- W2137762272 cites W2053174133 @default.
- W2137762272 cites W2054749028 @default.
- W2137762272 cites W2057781825 @default.
- W2137762272 cites W2058413852 @default.
- W2137762272 cites W2065011321 @default.
- W2137762272 cites W2073824318 @default.
- W2137762272 cites W2075133148 @default.
- W2137762272 cites W2075582522 @default.
- W2137762272 cites W2077298146 @default.
- W2137762272 cites W2077738720 @default.
- W2137762272 cites W2081443176 @default.
- W2137762272 cites W2087120414 @default.
- W2137762272 cites W2088100083 @default.
- W2137762272 cites W2088488472 @default.
- W2137762272 cites W2089475449 @default.
- W2137762272 cites W2090789986 @default.
- W2137762272 cites W2095384181 @default.
- W2137762272 cites W2096363558 @default.
- W2137762272 cites W2104676344 @default.
- W2137762272 cites W2107661454 @default.
- W2137762272 cites W2112977983 @default.
- W2137762272 cites W2117410573 @default.
- W2137762272 cites W2124901881 @default.
- W2137762272 cites W2137020607 @default.
- W2137762272 cites W2146922047 @default.