The Use of a Binary Composite Endpoint and Sample Size Requirement: Influence of Endpoints Overlap.

Although composite endpoints (CE) are common in clinical trials, the impact of the relationship between the components of a binary CE on the sample size requirement (SSR) has not been addressed. We performed a computational study considering 2 treatments and a CE with 2 components: the relevant endpoint (RE) and the additional endpoint (AE). We assessed the strength of the components' interrelation by the degree of relative overlap between them, which was stratified into 5 groups. Within each stratum, SSR was computed for multiple scenarios by varying the events proportion and the effect of the therapy. A lower SSR using CE was defined as the best scenario for using the CE. In 25 of 66 scenarios the degree of relative overlap determined the benefit of using CE instead of the RE. Adding an AE with greater effect than the RE leads to lower SSR using the CE regardless of the AE proportion and the relative overlap. The influence of overlapping decreases when the effect on RE increases. Adding an AE with lower effect than the RE constitutes the most uncertain situation. In summary, the interrelationship between CE components, assessed by the relative overlap, can help to define the SSR in specific situations and it should be considered for SSR computation.

Long-term outcome of aortic dissection with patent false lumen: predictive role of entry tear size and location.

BACKGROUND: Patent false lumen in aortic dissection has been associated with poor prognosis. We aimed to assess the natural evolution of this condition and predictive factors. METHODS AND RESULTS: One hundred eighty-four consecutive patients, 108 surgically treated type A and 76 medically treated type B, were discharged after an acute aortic dissection with patent false lumen. Transesophageal echocardiography was performed before discharge, and computed tomography was performed at 3 months and yearly thereafter. Median follow-up was 6.42 years (quartile 1 to quartile 3: 3.31-10.49). Forty-nine patients died during follow-up (22 type A, 27 type B), 31 suddenly. Surgical or endovascular treatment was indicated in 10 type A and 25 type B cases. Survival free from sudden death and surgical-endovascular treatment was 0.90, 0.81, and 0.46 (95% CI, 0.36-0.55) at 3, 5, and 10 years, respectively. Multivariate analysis identified baseline maximum descending aorta diameter (hazard ratio [HR]: 1.32 [1.10-1.59]; P=0.003), proximal location (HR: 1.84 [1.06-3.19]; P=0.03), and entry tear size (HR: 1.13 [1.08-1.2]; P<0.001) as predictors of dissection-related adverse events, whereas mortality was predicted by baseline maximum descending aorta diameter (HR: 1.36 [1.08-1.70]; P=0.008), entry tear size (HR: 1.1 [1.04-1.16]; P=0.001), and Marfan syndrome (HR: 3.66 [1.65-8.13]; P=0.001). CONCLUSIONS: Aortic dissection with persistent patent false lumen carries a high risk of complications. In addition to Marfan syndrome and aorta diameter, a large entry tear located in the proximal part of the dissection identifies a high-risk subgroup of patients who may benefit from earlier and more aggressive therapy.

Impact of clinical and health services research projects on decision-making: a qualitative study.

BACKGROUND: This article reports on the impact assessment experience of a funding program of non-commercial clinical and health services research. The aim was to assess the level of implementation of results from a subgroup of research projects (on respiratory diseases), and to detect barriers (or facilitators) in the translation of new knowledge to informed decision-making. METHODS: A qualitative study was performed. The sample consisted of six projects on respiratory diseases funded by the Agency for Health Quality and Assessment of Catalonia between 1996 and 2004. Semi-structured interviews to key informants including researchers and healthcare decision-makers were carried out. Interviews were recorded, transcribed verbatim and analysed on an individual (key informant) and group (project) basis. In addition, the differences between achieved and expected impacts were described. RESULTS: Twenty-three semi-structured interviews were conducted. Most participants indicated changes in health services or clinical practice had resulted from research. The channels used to transfer new knowledge were mainly conventional ones, but also in less explicit ways, such as with the involvement of local scientific societies, or via debates and discussions with colleagues and local leaders. The barriers and facilitators identified were mostly organizational (in research management, and clinical and healthcare practice), although there were also some related to the nature of the research as well as personal factors. Both the expected and achieved impacts enabled the identification of the gaps between what is expected and what is truly achieved. CONCLUSIONS: In this study and according to key informants, the impact of these research projects on decision-making can be direct (the application of a finding or innovation) or indirect, contributing to a more complex change in clinical practice and healthcare organization, both having other contextual factors. The channels used to transfer this new knowledge to clinical practice are complex. Local scientific societies and the relationships between researchers and decision-makers can play a very important role. Specifically, the relationships between managers and research teams and the mutual knowledge of their activity have shown to be effective in applying research funding to practice and decision-making. Finally the facilitating factors and barriers identified by the respondents are closely related to the idiosyncrasy of the human relations between the different stakeholders involved.

Noncompliance with certain quality indicators is associated with risk-adjusted mortality after stroke.

BACKGROUND AND PURPOSE: To investigate the 30-day and 12-month mortality risks among hospitalized stroke patients according to compliance with guideline-based process indicators. METHODS: We used data from the Second Stroke Audit and the Mortality Register of Catalonia (Spain). The audit retrospectively explored quality of stroke care based on compliance with indicators among patients discharged from all public hospitals in Catalonia in 2007; they were identified and selected through a pre-established sampling method. The magnitude of the independent association of each indicator with 30-day and 12-month mortality was assessed using logistic regression with generalized estimating equations to account for clustering of patients within hospitals. Generalized estimating equations modeling was initially restricted to patients alive >72 hours poststroke to control for confounding by severity. Analyses were also run in 3 other samples (all patients, patients alive >7 days, and patients alive >14 days). RESULTS: Of 1767 stroke admissions in the Second Stroke Audit, 1697 patients survived >72 hours poststroke. Within this sample, the adjusted 30-day mortality risk was negatively associated with nonadherence to different indicators, of which only antithrombotics at discharge (OR, 4.3; 95% CI, 1.72-10.78) remained significant in all data sets. At 12 months, the adjusted mortality risk was negatively associated with management of hypertension (OR, 1.87; 95% CI, 1.22-2.86) and antithrombotics at discharge (OR, 2.79; 95% CI, 1.41-5.54). Both remained unchanged across different samples. CONCLUSIONS: Assessing the impact of quality of stroke care on mortality is complex and is hampered by residual confounding, particularly in the short-term. Nevertheless, this study suggests that at least a few indicators should be used to monitor quality of stroke services.

Background, incidence, and predictors of antiplatelet therapy discontinuation during the first year after drug-eluting stent implantation.

BACKGROUND: Predictors of antiplatelet therapy discontinuation (ATD) during the first year after drug-eluting stent implantation are poorly known. METHODS AND RESULTS: This was a prospective study with 3-, 6-, 9-, and 12-month follow-up of patients receiving at least 1 drug-eluting stent between January and April 2008 in 29 hospitals. Individual- and hospital-level predictors of ATD were assessed by hierarchical-multinomial regression analysis. ATD could be assessed in 1622 candidates for follow-up (82.5%). A total of 234 patients (14.4%) interrupted at least 1 antiplatelet therapy drug, predominantly clopidogrel (n=182, 11.8%). Bleeding events or invasive procedures led to ATD in 109 patients. This was predicted by renal impairment (odds ratio [OR] 2.81, 95% confidence interval [CI] 1.48 to 5.34), prior major hemorrhage (OR 3.77, 95% CI 1.41 to 10.03), and peripheral arterial disease (OR 1.78, 95% CI 1.01 to 3.15). Medical decisions led to ATD in 70 patients; this was predicted by long-term use of anticoagulant therapy (OR 3.88, 95% CI 1.26 to 11.98), undergoing the procedure in a private hospital (OR 13.3, 95% CI 1.69 to 105), and not receiving instructions about medication (OR 2.8, 95% CI 1.23 to 6.36). Thirty-nine patients interrupted ATD on their own initiative, mainly immigrants (OR 3.78, 95% CI 1.2 to 11.98) and consumers of psychotropic drugs (OR 2.58, 95% CI 1.3 to 5.12). CONCLUSIONS: ATD during the first year after drug-eluting stent implantation is based mainly on patient decision or a medical decision not associated with major bleeding events or major surgical procedures. Individual- and hospital-level variables are important to predict ATD.

"Do GRACE (Global Registry of Acute Coronary events) risk scores still maintain their performance for predicting mortality in the era of contemporary management of acute coronary syndromes?".

BACKGROUND: Although the GRACE risk scores (RS) are the preferred scoring system for risk stratification in acute coronary syndromes (ACS), little is known whether these RS still maintain their performance in the current era. We aimed to investigate this issue in a contemporary population with ACS. METHODS: The study population composed of patients enrolled in the MASCARA national registry. The GRACE RS were calculated for each patient. Discrimination and calibration were evaluated with the C statistic and the Hosmer-Lemeshow test, in the whole population and according to the type of ACS, risk strata, and whether the patient had a history of diabetes and/or chronic renal failure. We determined if left ventricular ejection fraction (LVEF) provides incremental prognostic information above that established by the RS and whether percutaneous coronary intervention (PCI) during admission affects the performance of the score for predicting 6-month mortality. RESULTS: The 5,985 patients constituted the validation cohort for the in-hospital mortality RS and 5,635 the validation cohort for the 6-month mortality RS. Overall, both GRACE RS demonstrated excellent discrimination (C > 0.80) and calibration (all P values in Hosmer-Lemeshow >.1). Although similar results were seen in all subgroups, the 6-month mortality RS performed significantly less well in patients undergoing PCI compared to those patients who did not (C = 0.73 vs 0.76, P < .004). Adding LVEF to the RS did not convey significant prognostic information. CONCLUSIONS: The GRACE RS for predicting in-hospital and 6-month mortality still maintain their excellent performance in a contemporary cohort of patients with ACS. Further studies are needed to investigate the performance of the 6-month mortality GRACE score in patients undergoing in-hospital PCI. Left ventricular ejection fraction did not convey significant information over that provided by the RS.

[Information, knowledge and healthcare practice: professionals participation as the key element of the gear]. / Información, conocimiento y práctica sanitaria: la participación de los profesionales como pieza clave del engranaje.

This article analyzes the role of ICT within the complicated gear between information, knowledge and healthcare practices, which particular focus on two specific cases: the digitalization process of the healthcare system and the application of knowledge into the healthcare practices. In both cases, international and local experiences suggest, and sometimes demonstrate the importance of the participation, capacity-building and empowerment of healthcare practitioners for the generation, transfer and use of information and knowledge empowered by the digital tools which should bring into the system better performance, more efficacy, efficiency, equity, equality, security, quality.

[Exhaustivity and critical tone of the news in print media reporting medical innovations]. / Exhaustividad y tono crítico de las noticias en la prensa escrita que informan de una innovación médica.

OBJECTIVE: To quantify how exhaustive and critical were stories reporting medical innovations published in print media and to analyze the characteristics that may be related. METHOD: Content analysis of the newspapers stories related to the discovery, introduction or improvement of a medical innovation through a questionnaire with ten criteria that allows calculating an overall score of exhaustiveness. The critical view was also included. RESULTS: We analyzed 204 newspapers stories that on average obtained a comprehensiveness score of 4.5. Were optimistic 70% of the stories. The most valued criteria were: level of detail of the explanation of the innovation and the correct differentiation between facts and opinions. While the worst-valued criteria were: disclosure of financial conflicts of interest and the quantification of harms. The variables author, length of the story and classification of the innovation were related to both the comprehensiveness score and the critical view. The comprehensiveness score was also related to the pathology, number of sources of information and the critical tone of the story, while the critical view was also related to the newspapers diffusion and the relevance of the news. CONCLUSIONS: The analyzed stories presented inaccuracies, biases or an excess of optimism (either intentional or involuntary). Some aspects of the stories discussed in more detail would provide solutions to many of the identified shortcomings.

Long-term vasodilator therapy in patients with severe aortic regurgitation.

BACKGROUND: Vasodilator therapy can reduce the left ventricular volume and mass and improve left ventricular performance in patients with aortic regurgitation. Accordingly, it has been suggested that such therapy may reduce or delay the need for aortic-valve replacement. METHODS: We randomly assigned 95 patients with asymptomatic severe aortic regurgitation and normal left ventricular function to receive open-label nifedipine (20 mg every 12 hours), open-label enalapril (20 mg per day), or no treatment (control group) to identify the possible beneficial effects of vasodilator therapy on left ventricular function and the need for aortic-valve replacement. RESULTS: After a mean of seven years of follow-up, the rate of aortic-valve replacement was similar among the groups: 39 percent in the control group, 50 percent in the enalapril group, and 41 percent in the nifedipine group (P=0.62). In addition, there were no significant differences among the groups in aortic regurgitant volume, left ventricular size, left ventricular mass, mean wall stress, or ejection fraction. One year after valve replacement, the left ventricular end-diastolic diameter and end-systolic diameter had decreased to a similar degree among the patients who underwent surgery in each of the three groups, and all the patients had a normal ejection fraction. CONCLUSIONS: Long-term vasodilator therapy with nifedipine or enalapril did not reduce or delay the need for aortic-valve replacement in patients with asymptomatic severe aortic regurgitation and normal left ventricular systolic function. Furthermore, such therapy did not reduce the aortic regurgitant volume, decrease the size of the left ventricle, or improve left ventricular function.

Patterns of use and effectiveness of early invasive strategy in non-ST-segment elevation acute coronary syndromes: an assessment by propensity score.

BACKGROUND: The patterns of use and the benefit of an early invasive strategy (EIS) in patients with non-ST-segment elevation acute coronary syndrome in a real-life population are not well established. METHODS: All consecutive patients hospitalized because of non-ST-segment elevation acute coronary syndrome between November 2004 and June 2005 in 32 randomly selected hospitals were prospectively included. Patients were stratified by their baseline risk profile using the Global Registry of Acute Coronary Events (GRACE) risk score in 2 groups. Inhospital mortality and 1- and 6-month mortality or rehospitalization for acute coronary syndromes were analyzed. To ensure optimal adjustment propensity score, conventional logistic regression and Cox regression were used. RESULTS: Of 2,856 patients analyzed, 1,616 (56%) had low/intermediate risk (GRACE140). Patients who underwent EIS had lower risk than those who did not (GRACE score 128.2+/-41 vs 138.5+/-43, P<.001). Coronary angiography facility emerged as the strongest predictor of EIS (odds ratio [OR] 13.7 [95% CI 7.1-25]). Patients who underwent EIS had lower rate of the 6-month outcome in both the whole population (9% [95% CI 6.6-11.9] vs 14% [95% CI 12.5-15.6], P=.003) and in high-risk patients (16.5% [95% CI 11-23] vs 23.6% [95% CI 20.8-26.5], P=.04). However, this benefit of EIS was not apparent after statistical adjustment in the whole population (OR 0.8, CI 0.55-1.1, P=.17) or in high-risk patients (OR 0.7, CI 0.46-1.1, P=.16). CONCLUSIONS: In a real-life population, EIS was mainly performed in patients of low/intermediate risk. An obvious benefit of this strategy could not be found.

The EuroSCORE and a local model consistently predicted coronary surgery mortality and showed complementary properties.

OBJECTIVE: To revalidate a local model for prediction of in-hospital mortality after coronary surgery several years after its introduction and the EuroSCORE in a specific area within its original scope. To assess the specific advantages of one type of instrument over the other in a definite context. STUDY DESIGN AND SETTING: Data from consecutive patients undergoing a first isolated coronary artery bypass between November 2001 and November 2003 in five hospitals in Catalonia were prospectively collected. RESULTS: The study included 1,605 patients. Areas under the receiver-operating characteristics curves were around 0.75 for both models. Calibration was low for both models and the local model significantly overestimated risk. The ordering of operating centers by performance was identical with each strategy but the centers labeled as outliers differed. CONCLUSION: (1) Evaluation of performance of individual hospitals was consistent using both systems and almost identical when they were internally recalibrated, (2) The impact of the benchmark population characteristics on model performance may be greater than that of risk factors considered for score calculation, (3) Promoting the use of a widely used instrument as the EuroSCORE might be sufficient for most evaluations. Local scales can be useful to highlight locally relevant features and temporal trends.

Low-pressure cardiac tamponade: clinical and hemodynamic profile.

BACKGROUND: Low-pressure cardiac tamponade is a form of cardiac tamponade in which a comparatively low pericardial pressure results in cardiac compression because of low filling pressure. This syndrome is poorly characterized because only isolated cases have been reported. We conducted a study of its clinical and hemodynamic profiles. METHODS AND RESULTS: From 1986 through 2004, we evaluated all patients at our institution with combined pericardiocentesis and cardiac catheterization. We identified those patients who fulfilled catheterization-based criteria of low-pressure cardiac tamponade and compared their clinical and catheterization data with those of patients with classic tamponade. A total of 1429 patients with pericarditis were evaluated, 279 of whom underwent combined pericardiocentesis and catheterization. Criteria of low-pressure cardiac tamponade were met in 29, whereas 114 had criteria of classic cardiac tamponade. Patients with low-pressure tamponade less frequently had clinical signs of tamponade, but the rate of constitutional symptoms, use of diuretics, and echocardiographic findings of tamponade were similar in both groups. Patients with low-pressure tamponade showed a significant increase in cardiac output after pericardiocentesis, but they usually had less severe cardiac tamponade compared with patients with classic tamponade. Prognosis was related mainly to the underlying disease. CONCLUSIONS: Low-pressure cardiac tamponade was identified in 20% of patients with catheterization-based criteria of tamponade. Clinical recognition may be difficult because of the absence of typical physical findings of tamponade in most patients. Although some patients are critically ill, most show a stable clinical condition. However, these patients obtain a clear benefit from pericardiocentesis.

Effusive-constrictive pericarditis.

BACKGROUND: Effusive-constrictive pericarditis is an uncommon pericardial syndrome characterized by concomitant tamponade, caused by tense pericardial effusion, and constriction, caused by the visceral pericardium. We conducted a prospective study of its clinical evolution and management. METHODS: From 1986 through 2001, all patients with effusive-constrictive pericarditis were prospectively evaluated. Combined pericardiocentesis and cardiac catheterization were performed in all patients, and pericardiectomy was performed in those with persistent constriction. Follow-up ranged from 1 month to 15 years (median, 7 years). RESULTS: A total of 1184 patients with pericarditis were evaluated, 218 of whom had tamponade. Of these 218, 190 underwent combined pericardiocentesis and catheterization. Fifteen of these patients had effusive-constrictive pericarditis and were included in the study. All patients presented with clinical tamponade; however, concomitant constriction was recognized in only seven patients. At catheterization, all patients had elevated intrapericardial pressure (median, 12 mm Hg; interquartile range, 7 to 18) and elevated right atrial and end-diastolic right and left ventricular pressures. After pericardiocentesis, the intrapericardial pressure decreased (median value, -5 mm Hg; interquartile range, -5 to 0), whereas right atrial and end-diastolic right and left ventricular pressures, although slightly reduced, remained elevated, with a dip-plateau morphology. The causes were diverse, and death was mainly related to the underlying disease. Pericardiectomy was required in seven patients, all of whom had involvement of the visceral pericardium. Three patients had spontaneous resolution. CONCLUSIONS: Effusive-constrictive pericarditis is an uncommon pericardial syndrome that may be missed in some patients who present with tamponade. Although evolution to persistent constriction is frequent, idiopathic cases may resolve spontaneously. In our opinion, extensive epicardiectomy is the procedure of choice in patients requiring surgery.

Methodologic discussions for using and interpreting composite endpoints are limited, but still identify major concerns.

OBJECTIVE: To investigate the rationale, potential problems and solutions of using composite endpoints (CEPs) for the assessment of intervention effects. STUDY DESIGN AND SETTING: This study is a systematic review. We searched MEDLINE, EMBASE, and the Science Citation Index, for publications appearing between 1980 and September 2005, and reviewed potentially informative textbooks. Eligible articles provided a commentary, analysis, or discussion of CEPs for any of the following areas: (1) rationale, (2) interpretation or meaning, (3) advantages, (4) limitations or conceptual problems, and (5) recommendations for use. RESULTS: Seventeen articles and one textbook proved eligible. Decreases in sample size requirements and ability to assess the net effect of an intervention were the most commonly cited advantages. Authors noted the risk of misinterpretation when heterogeneity among components with respect to either patient importance or magnitude of treatment effects as the most salient disadvantage. There were discrepancies between authors concerning the usefulness of CEPs to avoid bias from competing risks and when the direction of the effect of therapy differs across components. CONCLUSION: Methodologists have given limited attention to CEPs and their views are sometimes contradictory. Further work is needed to establish the role of CEPs in research and in guiding clinical practice.

[Evaluation of risk-adjusted hospital mortality after coronary artery bypass graft surgery in the Catalan public healthcare system. Influence of hospital management type (ARCA Study)]. / Evaluación de la mortalidad hospitalaria ajustada al riesgo de la cirugía coronaria en la sanidad pública catalana. Influencia del tipo de gestión del centro (estudio ARCA).

INTRODUCTION AND OBJECTIVES: Previous studies suggest that the effectiveness of coronary surgery is influenced by the type of management at the healthcare centre where the intervention is performed. The present study assessed the risk-adjusted hospital mortality of coronary surgery in the Catalan healthcare system in hospitals under either private or public management. METHODS: We carried out a prospective study of all consecutive patients receiving a first coronary artery bypass graft, with public financial support, in a period of 2 years at 5 hospitals under either public or private management. Preoperative risk was assessed using the EuroSCORE and Catalan Agency for Health Technology Assessment (CAHTA) predictive models. RESULTS: Overall, 1605 patients underwent interventions, 21% of which were at private hospitals. The percentage of patients undergoing non-elective surgery was higher at private hospitals (64% vs 50%), as was the percentage needing intravenous nitrates (17% vs 11%) and the percentage in functional class IV (20% vs 11%). The odds ratio for in-hospital mortality in private compared with public hospitals was 0.56 (95% CI, 0.29-1.06) when adjusted for EuroSCORE, 0.56 (95% CI, 0.29-1.07) when adjusted for CAHTA score, and 0.43 (95% CI, 0.21-0.87) when adjusted for patient characteristics. The mortality observed, 4.8% (95% CI 3.8-5.6), was not significantly higher than that predicted. CONCLUSIONS: a) Hospital mortality was equivalent to or lower than that expected after adjustment for the 2 risk scores; b) after adjustment for baseline patient characteristics, the results favored privately managed centers; and c) comparison with previous results suggests that coronary surgery effectiveness has improved in recent years.

Long-term follow-up of aortic intramural hematoma: predictors of outcome.

BACKGROUND: Aortic intramural hematoma (IMH) evolves very dynamically in the short-term to regression, dissection, or aortic rupture. The aim of the present study was to assess the long-term clinical and morphological evolution of medically treated IMH. METHODS AND RESULTS: Fifty of 68 consecutive patients with aortic IMH monitored clinically and by imaging techniques at 3, 6, and 12 months and annually thereafter were prospectively studied. Mean follow-up was 45+/-31 months. In the first 6 months, total IMH regression was observed in 14 and progression to aortic dissection in 18 patients; in 14 of these, the dissection was localized, and 12 later developed pseudoaneurysm. At the end of follow-up, the IMH had regressed completely without dilatation in 17 patients (34%), progressed to classical dissection in 6 (12%), evolved to fusiform aneurysm in 11 (22%), evolved to saccular aneurysm in 4 (8%), and evolved to pseudoaneurysm in 12 (24%). Evolution to dissection was related to echolucency (P<0.02) and to longitudinal extension of IMH (P<0.01). Multivariate analysis showed an independent association between regression and smaller maximum aortic diameter and between aneurysm formation and atherosclerotic ulcerated plaque and absence of echolucent areas in IMH. CONCLUSIONS: The most frequent long-term evolution of IMH is to aortic aneurysm or pseudoaneurysm. Complete regression without changes in aorta size is observed in one third of cases, and progression to classical dissection is less common. A normal aortic diameter in the acute phase is the best predictor of IMH regression without complications, and absence of echolucent areas and atherosclerotic ulcerated plaque are associated with evolution to aortic aneurysm.

[Diagnosis and management of acute pericardial syndromes]. / Orientación diagnóstica y manejo de los síndromes pericárdicos agudos.

Essentially, acute pericardial syndromes include acute pericarditis and cardiac tamponade. This article focuses on the diagnosis and management of acute pericarditis. In Spain, most cases of acute pericarditis whose etiology is not apparent at initial clinical presentation are either idiopathic or viral pericarditis, which follow a benign or self-limiting clinical course (although tamponade may develop in some patients). Knowledge of this basic epidemiologic fact is essential for the development of a rational management protocol that, on the one hand, avoids the unnecessary use of invasive pericardial diagnostic procedures in patients with idiopathic pericarditis and that, on the other hand, correctly identifies most cases of specific pericarditis, which mainly comprise purulent, tuberculous or neoplastic pericarditis. In accordance with this rationale and on the basis of our own experience, we have proposed a protocol for the management of acute pericardial disease that differs markedly from the "Guidelines on the Diagnosis and Management of Pericardial Disease" recently produced by the European Society of Cardiology. In addition, we have made some comments on the cardiac tamponade and the acute and subacute constrictive pericarditis that can occur during the resolution of acute pericarditis.

[The Spanish version of the Short Form 36 Health Survey: a decade of experience and new developments]. / El Cuestionario de Salud SF-36 español: una década de experiencia y nuevos desarrollos.

OBJECTIVE: The Short Form-36 Health Survey (SF-36) is one of the most widely used and evaluated generic health-related quality of life (HRQL) questionnaires. After almost a decade of use in Spain, the present article critically reviews the content and metric properties of the Spanish version, as well as its new developments. METHODS: A review of indexed articles that used the Spanish version of the SF-36 was performed in Medline (PubMed), the Spanish bibliographic databases IBECS and IME. Articles that provided information on the measurement model, reliability, validity, and responsiveness to change of the instrument were selected. RESULTS: Seventy-nine articles were found, of which 17 evaluated the metric characteristics of the questionnaire. The reliability of the SF-36 scales was higher than the suggested standard (Cronbach's alpha) of 0.7 in 96% of the evaluations. Grouped evaluations obtained by meta-analysis were higher than 0.7 in all cases. The SF-36 showed good discrimination among severity groups, moderate correlations with clinical indicators, and high correlations with other HRQL instruments. Moreover, questionnaire scores predicted mortality and were able to detect improvement due to therapeutic interventions such as coronary angioplasty, benign prostatic hyperplasia surgery, and non-invasive positive pressure home ventilation. The new developments (norm-based scoring, version 2, the SF-12 and SF-8) improved both the metric properties and interpretation of the questionnaire. CONCLUSIONS: The Spanish version of the SF-36 and its recently developed versions is a suitable instrument for use in medical research, as well as in clinical practice.