Introduction: The term quality of life has gained increasing importance in the scientific context. This study describes the adaptation of a disease-specific questionnaire developed by Paul Jones et al. in 1991, the St. George's Respiratory Questionnaire (SGRQ), to the Brazilian language and culture. This questionnaire evaluates the quality of life in patients with chronic obstructive pulmonary disease (COPD) and contains three domains (symptoms, activity, and impacts) divided in 76 items. The questionnaire is self-administrated, but it may be read to illiterate persons. Goal: To verify if the St. George's Respiratory Questionnaire is a valid tool to measure quality of life in patients with chronic obstructive pulmonary disease in Brazil. Methods: In order to validate the questionnaire in Brazil, it was initially translated into Portuguese and afterwards a back-translation into English, that was compared to the original version. A final Portuguese version was then written. This final version was, then, answered by 30 clinically stable COPD patients, according to the spirometry and oximetry values. Patients answered the questionnaire twice, within a 15 day interval. The length of time the patients took to answer the questionnaire and their doubts were noted. Wilcoxon test was used for the calculation of r probability between every single question between the two days; interclass correlation ratio was calculated to test the trustworthiness and reliability of the questionnaire. Results: Among the 30 participant patients, 10 were female and 20 were male. Mean age was 65.9 years. Most of the patients were found to be in stage 2 (56.7 %) of COPD, according to the American Thoracic Society classification. The interclass correlation ratio for the total score of the questionnaire was a = 0.79 and Wilcoxon p = 0.2110 (not statistically significant). The mean answering time for the two days of interview was, respectively, 11 minutes and 50 seconds and 10 minutes and 31 seconds. As concerns the doubts about the questions, the patients reported difficulties in answering Sections 4 and 5, each one of these questions written in a negative form. Conclusion: It can be concluded that the Brazilian version of the St. George's Respiratory Questionnaire is a valid and reliable tool to measure quality of life in patients with COPD in Brazil.

Keywords: obstructive lung diseases, questionnaire, quality of life, reproducibility of results, evolution studies

Objective: The objective of this study was to evaluate the applicability of a modified version of the Saint George's Respiratory Questionnaire. The version evaluated elicits "agree" and "do not agree", rather than "yes" and "no", responses. The intention is to facilitate the comprehension of double-negative questions and to promote better recollection of symptoms by patients by shortening their symptom histories from 12 months to 3 months. Methods: A total of 30 clinically stable patients with chronic obstructive pulmonary disease were evaluated. The Saint George's Respiratory Questionnaire and the modified version of the same were administered 15 days apart. Results: All of the patients presented health-related alterations in their quality of life. Comparing mean scores between the two questionnaires, the greatest difference was seen in the Symptoms domain. No significant differences were found in any of the remaining domains or in the total scores. In a subsequent analysis, significant correlations between the two questionnaires were found in all domains: Symptoms (r = 0.71; p < 0.001); Activity (r = 0.75; p < 0.001); Impact (r = 0.73; p < 0.001) and Total (r = 0.86; p < 0.001). Conclusion: The modified version of the Saint George's Respiratory Questionnaire is as effective as the original in gauging quality of life. However, various symptoms recollection time frames should be investigated in order to determine which would be the best time frame to employ in the analysis.

Keywords: Pulmonary disease, chronic obstructive; Quality of life; Reproducibility of results; Cross-cultural comparison; Questionnaires

Abstract Objective: To determine the validity and reproducibility of two subjective instruments to assess limitations in activities of daily living (ADLs) in patients with chronic obstructive pulmonary disease (COPD) in Brazil: the Pulmonary Functional Status and Dyspnea ­Questionnaire ‑ ­Modified version (PFSDQ-M) and the Medical Research Council (MRC) scale. Methods: Thirty patients with COPD (age, 67 ± 10 years; males, 17; forced expiratory volume in one second, 42% ± 13% of predicted) completed the Portuguese-language versions of the two instruments on two occasions, one week apart. The PFSDQ-M has three components: influence of dyspnea on ADLs, influence of fatigue on ADLs and change experienced by the patient with ADLs. The MRC scale is simple, with only five items, in which patients report the degree to which dyspnea limits their performance of ADLs. The traditional Saint George's Respiratory Questionnaire (SGRQ), previously validated for use in Brazil, was used as a validation criterion. Results: The test-retest reliability (intraclass correlation coefficient) of the PFSDQ-M was 0.93, 0.92 and 0.90 for the dyspnea, fatigue and change components, respectively, compared with 0.83 for the MRC scale. Bland-Altman plots showed good test-retest concordance for the PFSDQ-M. The components of the PFSDQ-M and the MRC scale correlated significantly with all of the domains and the total score on the SGRQ (0.49 < r < 0.80; p < 0.01 for all). Conclusions: The Portuguese-language versions of the PFSDQ-M and the MRC scale proved reproducible and valid for use in patients with COPD in Brazil.

Keywords: Pulmonary disease, chronic obstructive; Activities of daily living; Validation studies.

Introduction: A great emphasis has been placed on health-related quality of life of COPD patients and specific questionnaires have been developed in order to measure it. Interventions directed to improve symptoms and decrease morbi-mortality may be evaluated by such questionnaires. Objective: This study describes the language and cultural adaptation of a new (and short) disease-specific health status questionnaire developed for chronic obstructive pulmonary diseases: the Airways Questionnaire 20 (AQ20). This questionnaire has only 20 simple items, and is one of the shortest ones ever described in the literature. Methods: In order to validate this questionnaire in Brazil, an initial translation from English to Portuguese has been made. The cultural adaptation was taken into consideration and then a back translation to English was undertaken, in order to obtain a final Portuguese version. Correlations were made with FEV1, SpO2, BMI and another disease specific health status questionnaire, the Saint George Respiratory Questionnaire (SGRQ), previously validated in Brazil. To test the reproducibility of AQ20, the interclass correlation ratio was done. Results: The interclass correlation ratio for the total score was a = 0.90 (intraobserver variability) and a = 0.93 (interobserver variability). The correlation with total SGRQ score was 0.76, with p < 0.001. Conclusion: It can be concluded that the Brazilian Portuguese version of AQ20 is reproducible, with good correlation with SGRQ total score, which makes it a valid questionnaire to measure health status in obstructive patients in Brazil.

Introduction: Spirometry and analysis of blood gases data have been extensively used to assess ventilatory limitation and prognosis of COPD patients. However, functional physical tests, such as the six-minute walk test (6wt) have been used for the dynamic assessment of COPD patients. Objective: To determine correlations between respiratory function test data and the six-minute walk test in COPD patients. Patients and methods: 45 patients were submitted to clinical history survey and complete physical examination performed by the medical staff of the Pneumology Department of the Brasilia University Hospital, followed by spirometry, analysis of arterial blood gases, maximal respiratory pressures data, and the six-minute walk test. Results: Concerning the spirometric, analysis of blood gases and maximal respiratory pressures data, statistically significant positive correlations (p < 0.05) between FEV1, PaO2, SpO2, MEP and the six-minute walk test were obtained. Conclusions: For the studied group, the six minute walk test has significant correlation with FEV1, PaO2, SpO2 and MEP, and can be used as an alternative functional assessment of COPD patients.

Pulmonary thromboembolism and exacerbation of chronic obstructive pulmonary disease are common conditions. Chronic obstructive pulmonary disease is a clinical risk factor for pulmonary thromboembolism. The presentation of acute pulmonary thromboembolism and acute exacerbation of chronic obstructive pulmonary disease often mimic each other so closely that they cannot be distinguished clinically. The structural abnormalities of the lungs in chronic obstructive pulmonary disease make also difficult to interpret the results of noninvasive tests like ventilation-perfusion lung scans. Therefore, diagnosing acute pulmonary thromboembolism in patients with underlying chronic obstructive pulmonary disease is a challenging task. In order to update knowledge of the subject and offer suggestions regarding conduct, we evaluated various studies addressing this theme, including case reports and case series. In addition, we reviewed diagnostic approaches to acute pulmonary thromboembolism, and we reflect upon that topic. The clinical probability of pulmonary thromboembolism concomitant to chronic obstructive pulmonary disease is typically intermediate, as is positivity on the ventilation-perfusion lung scan. Diagnostic algorithms should take that into consideration.

Keywords: Pulmonary disease, chronic obstructive/complications; Pulmonary embolism/diagnosis; Pulmonary embolism/epidemiology; Ventilation-perfusion ratio

Background: Pulmonary rehabilitation is widely recommended for the treatment of chronic obstructive pulmonary disease. Objective: To evaluate the efficacy of pulmonary rehabilitation in improving exercise capacity, respiratory muscle strength and quality of life of chronic obstructive pulmonary disease patients. Method: This was an open, non-randomized clinical trial involving 27 clinically stable ex-smokers with chronic obstructive pulmonary disease who were enrolled in a pulmonary rehabilitation program. All were evaluated before and after pulmonary rehabilitation. Results: Mean age was 65 ± 5 years, mean body mass index was 25 ± 4 kg/m2, mean forced expiratory volume in one second was 55 ± 25% of predicted, mean ratio between forced expiratory volume in one second and forced vital capacity was 50 ± 12%, and mean arterial oxygen tension was 70 ± 7 mmHg. Comparison of pre- and post-pulmonary rehabilitation values revealed improvement in the distance walked in the 6-minute walk test (513 ± 99 m vs. 570 ± 104 m), maximum upper limb load (2 ± 1 kg vs. 3 ± 1 kg) and maximal inspiratory pressure (-89 ± 23 cmH2O vs. -102 ± 23 cmH2O), as well as in the activity domain, impact domain and total score on the Saint George's Respiratory Questionnaire. Conclusion: Pulmonary rehabilitation, when performed with care and with a focus on physical training, is efficacious in increasing not only the distance walked in the 6-minute walk test but maximum upper limb load, maximal inspiratory pressure and quality of life as well.

Keywords: Key words: Pulmonary rehabilitation. Chronic obstructive pulmonary disease. Quality of life. Respiratory muscles.

Objective: To translate, adapt and validate the Patient Generated Index (PGI) for Brazilians with chronic obstructive pulmonary disease (COPD). Methods: 50 volunteers with COPD, mostly men (74%), with 73.1 ± 8.9 years of age, FEV1 of 52.3 ± 14.5% of predicted and FEV1 / FVC of 56.2 ± 8.6% of predicted responded to PGI, to the Saint George Respiratory Questionnaire (SGRQ) and to perform Glittre Activities of Daily Living test (Glittre ADL). After 1-2 weeks, PGI was again applied for the analysis of relative and absolute reliability. Results: The translation occurred without changes in the questionnaire. The score obtained in PGI had weak correlation with the SGRQ total score (r = -0.44, p <0.001) and with the impact domain (r = -0.40, p <0.05), presented a moderate correlation with the symptoms domain of the SGRQ (r = -0.55, p <0.001) and weak correlation with the activity domain (r = -0.31, p <0.05). A weak correlation was observed between PGI and Glittre ADL (r = -0.30; p <0.05). It was observed high reliability among the measures of PGI (ICCr = 0.94). Conclusion: This study shows that the Brazilian version of PGI is a reliable and valid instrument to measure health‑related quality of life (HRQL) in patients with COPD. It is a new and individualized form of evaluation of COPD patient-centered quality of life.

Keywords: Quality of life; Chronic obstructive pulmonary disease; Reproducibility of results and translations.

Objective: To validate the Portuguese-language version of the STOP-Bang (acronym for Snoring, Tiredness, Observed apnea, high blood Pressure, Body mass index, Age, Neck circumference, and Gender) questionnaire, culturally adapted for use in Brazil, as a means of screening for obstructive sleep apnea (OSA) in adults. Methods: In this validation study, we enrolled patients ≥ 18 years of age, recruited between May of 2015 and August of 2016. All patients completed the STOP-Bang questionnaire and underwent overnight polysomnography. To evaluate the performance of the questionnaire, we used contingency tables and areas under the (receiver operating characteristic) curve (AUCs). Results: We included 456 patients. The mean age was 43.7 ± 12.5 years, and 291 (63.8%) of the patients were male. On the basis of the apnea-hypopnea index (AHI), we categorized OSA as mild/moderate/severe (any OSA; AHI ≥ 5 events/h), moderate/severe (AHI ≥ 15 events/h), or severe (AHI ≥ 30 events/h). The overall prevalence of OSA was 78.3%, compared with 52.0%, and 28.5% for moderate/severe and severe OSA, respectively. The most common score on the STOP-Bang questionnaire was 4 points (n = 106), followed by 3 points (n = 85) and 5 points (n = 82). An increase in the score was paralleled by a reduction in sensitivity with a corresponding increase in specificity for all AHI cut-off points. The AUCs obtained for the identification of any, moderate/severe, and severe OSA were: 0.743, 0.731, and 0.779, respectively. For any OSA, the score on the questionnaire (cut-off, ≥ 3 points) presented sensitivity, specificity, and accuracy of 83.5%, 45.5%, and 75.2%, respectively. Conclusions: The STOP-Bang questionnaire performed adequately for OSA screening, indicating that it could be used as an effective screening tool for the disorder.

Keywords: Sleep apnea, obstructive/diagnosis; Polysomnography; Diagnostic techniques and procedures; Surveys and questionnaires.

Objective: To describe and analyze clinical symptoms and spirometric alterations of patients with chronic obstructive pulmonary disease (COPD) and history of exposure to wood and tobacco smoke. Methods: We retrospectively evaluated data related to 170 patients distributed into 3 groups: 34 exposed only to wood smoke, 59 patients exposed only to tobacco smoke and 77 patients exposed to both. Results: The groups did not differ significantly in terms of age (p = 0.225) or degree of exposure, considering each type of exposure in isolation or in combination (p = 0.164 and p = 0.220, respectively). Females predominated in the group exposed to wood smoke. There were no differences among the groups regarding respiratory symptoms (p > 0.05), and moderate dyspnea predominated in the three groups (p = 0.141). The group exposed to wood smoke presented higher percentages of forced expiratory volume in one second/forced vital capacity ratio and of forced expiratory volume in one second (p < 0.05). Positive results on bronchodilator testing occurred more frequently in the group exposed to tobacco smoke. The percentage of severe and extremely severe obstruction was significantly higher in the group exposed to tobacco smoke (44.1%) than in that exposed to wood smoke (11.8%; p = 0.006). Conclusions: Respiratory symptoms and pulmonary function alterations consistent with COPD were observed in the groups of patients exposed to wood smoke. However, those alterations were not as significant as the alterations observed in the groups exposed to tobacco smoke. This study emphasizes the importance of prospective studies in evaluating the risk of wood-smoke-related COPD in Brazil, as well as the need for preventive measures in this area.

Keywords: Pulmonary disease, chronic obstructive; Smoking; Air pollution, indoor; Smoke.

Chronic obstructive pulmonary disease is a prevalent condition and is currently the forth leading cause of mortality in the US. The prevalence of respiratory disturbance during sleep, or overlap syndrome as it was commonly known in the past, is still undetermined as conflicting reports have been published. Because of the adverse effects of sleep-related respiratory impairment in patients with underlying pulmonary disease, this condition deserves further investigation. In this report, we will briefly discuss the mechanisms involved in generating respiratory disturbance during sleep in Chronic Obstructive Pulmonary Disease and will guide the reader into distinguishing those patients who would benefit from a more detailed sleep evaluation, discussing management issues and treatment options.

Keywords: Key words: COPD. Sleep disorder breathing. Sleep apnea. Hypoxemia. Hypoventilation

Objective: Making the differential diagnosis between asthma and chronic obstructive pulmonary disease (COPD) based on the response to inhaled bronchodilators by means of spirometry is controversial.The objective of this study was to identify the most useful spirometric variables in order to distinguish between asthma and COPD. Methods: Retrospective study conducted from April of 2004 to January of 2006, comparing the spirometric parameters of 103 nonsmoking patients with asthma to those of 108 patients with COPD who were smokers for more than 10 pack-years. All of the patients included in the study were older than 40 and presented stable disease at the time of the test. Results: Initial forced expiratory volume in one second (FEV1) was the same in the two groups (pre-bronchodilator FEV1 = 51%). However, patients with COPD were older (66 ± 9 years vs. 59 ± 11 years, p < 0.001) and more frequently male (73% vs. 27%, p < 0,001).After the use of the bronchodilator, the median absolute difference in FEV1 was 0.25 L (range, −0.09 to 1.13 L) in patients with asthma and 0.09 L (range, −0.1 to 0.73 L) in those with COPD (p < 0.001).The highest sensitivity (55%), specificity (91%) and likelihood ratio (6.1) for asthma diagnosis was obtained when the percentage increase in postbronchodilator FEV1 in relation to the predicted FEV1 (Δ%predFEV1) was equal to or greater than 10%.Isolated significant increases in forced vital capacity were more common in patients with COPD. Conclusions: In patients over the age of 40 and presenting obstructive lung disease, a Δ%predFEV1 ≥ 10% is the best spirometric parameter to distinguish asthma from COPD.

Keywords: Spirometry; Respiratory function tests; Lung diseases, obstructive.

Objective: To investigate the reliability, internal consistency and validity of the Brazilian Portuguese version of the University of California San Diego Shortness of Breath Questionnaire (UCSD SOBQ) in patients with interstitial lung disease (ILD). Methods: Patients with ILD completed the questionnaire at three different time points, one week apart, with the assistance of two independent assessors. Intra- and inter-rater reliability were analysed via the intraclass correlation coefficient (ICC). Internal consistency was assessed with the Cronbach's alpha coefficient. For the validity analysis, associations between variables were assessed with Spearman's or Pearson's correlation coefficient. Results: Thirty patients with ILD (idiopathic pulmonary fibrosis, connective tissue disease-associated pulmonary fibrosis, sarcoidosis, asbestosis or non-specific interstitial pneumonia) were included (15 men; mean age, 59 ± 10 years; DLCO: 46 [33-64] % predicted). UCSD SOBQ scores showed excellent agreement and internal consistency in the intra-rater analysis (ICC: 0.93 [0.85-0.97]; Cronbach alpha: 0.95) and in the inter-rater analysis (ICC: 0.95 [0.89-0.97]; Cronbach alpha: 0.95), as well as correlating significantly with dyspnoea (as assessed by the Medical Research Council scale; r = 0.56); Medical Outcomes Study 36-item Short-Form Health Survey domains bodily pain, general health, vitality and physical functioning (-0.40 = r = -0.74); six-minute walk distance (r = -0.38); and quadriceps muscle strength (r = -0.41). Conclusions: The Brazilian Portuguese version of the UCSD SOBQ is valid, is reliable and has internal consistency in patients with ILD in Brazil.

Keywords: Lung diseases, interstitial; Dyspnea; Surveys and questionnaires.

Depression is the most prevalent psychiatric disorder among hospitalized patients. Chronic obstructive pulmonary disease (COPD) is the most common pulmonary disease, responsible for a high incidence of hospitalization. The purpose of this study is to determine the prevalence of major depression in patients hospitalized due to COPD and correlate such depression with PaCO2, PaO2, respiratory infection, degree of functional airflow obstruction, and steroid therapy. Depression was diagnosed according to DSM IV criteria for major depressive disorders, and assessed by the Beck Depression Inventory. The interview, spirometry, and arterial blood gas analysis were performed between the third and the tenth day of hospitalization. The authors made a prospective study of 51 patients, 34 male and 17 female, with a mean age of 61 ± 11 years. Respiratory infection was the most frequent cause of hospital admission. Major depression was present in 26.9% (n = 11) of the patients, and proportionally higher in females (8 vs 3, p = 0.003). PaCO2 was higher in depressive patients than in non-depressive ones (60.1 ± 18.0 vs 45.8 ± 10.0 mmHg, p = 0.004). Other variables did not display significant differences. The authors conclude that major depression is highly prevalent among patients with COPD, specially in hypercapnic individuals and women.

Keywords: Chronic obstructive pulmonary disease. Steroid. Hypercapnia. Hypoxemia. Depression.

Background: Pulmonary Rehabilitation (PR) improves the quality of life of chronic obstructive pulmonary disease (COPD) patients. However, the influence of PR on the sleep pattern of these patients is unknown. Objective: To evaluate the influence of PR on the sleep patterns of patients with COPD. Method: A total of 27 patients (22 men/5 women) were submitted to polysomnographic, gasometric and anthropometric studies before and after six weeks of PR and were evaluated using the Epworth Sleepiness Scale. The results were analyzed using paired Student's t-test, ANOVA and Newman-Keuls multiple comparison test. Results: Mean age was 63.3 5.3 years, mean FEV1 was 54.8 25.4% of predicted, mean FEV1/FVC was 49.9 12.0% of predicted, mean resting PaO2 was 69.7 7.3 mmHg, and mean resting SaO2 was 93.7 2.1%. Polysomnography revealed sleep patterns to be fragmented, with frequent waking and reduced slow-wave sleep, as well as oxygen desaturation. The most significant drops in oxygen saturation occurred during rapid eye movement sleep. No significant differences were observed between pre- and post-PR values for the other variables studied (p > 0.05).Conclusion: In the group of patients studied, PR did not alter sleep patterns.

Keywords: Sleep. Pulmonary Disease. Chronic Obstructive. Lung Diseases, rehabilitation.

Background: The six minutes walk test has been increasingly utilized to assess the effectiveness of different clinical and surgical treatment options in pulmonary diseases. However lack of standardization for their performance may influence measurements and jeopardize assessment of the functional capacity of patients with cardiopulmonary disease. Objective: To determine the possible effects of learning on the distance covered during the six minute walk test for bearers of chronic obstructive pulmonary disease. Method: A retrospective analysis of 35 medical records of COPD patients referred to the Pulmonary Rehabilitation Program of the University Hospital of Brasília was carried out. On alternate days these patients had performed two six minutes walk tests, spirometry and arterial blood gas analysis. Clinical and functional diagnosis was based upon the history of exposure to risk factors, mucus production, dyspnea and spirometric dysfunction after use of bronchodilators. The Student test was used for the comparison of results that were different. Results: The distances covered in the second six-minute walk test (515 ± 82 meters) were greater than those covered in the first six-minute walk test (480 ± 85 metros), with statistically significant differences (p<0.05). However measurements of the muscular effort and perception of dyspnea (Borg scale), peripheral blood oxygen saturation (SpO2), respiratory and heart rates did not disclose any statistically significant differences between the two tests (p<0.05). Conclusion: The present study suggests that in order to standardize the six minutes walk test, the procedure should be performed at least twice to better assess the functional capacity of patients, bearers of chronic obstructive pulmonary disease.

Keywords: Walking. Effectiveness. Lung diseases, obstrutive.

Objective: To study the effects of nocturnal hypoxemia in patients with chronic obstructive pulmonary disease without obstructive sleep apnea syndrome. Methods: We studied 21 patients-10 desaturators and 11 nondesaturators-submitted to arterial blood gas analysis, polysomnography, spirometry, cardiopulmonary exercise testing (cycle ergometer), and hand-grip dynamometry, as well as measurements of maximal inspiratory pressure, maximal expiratory pressure, and C-reactive protein (CRP) levels. Patients with arterial oxygen tension > 60 mmHg were included; those with an apnea-hypopnea index > 5 events/hour of sleep were excluded. Maximal oxygen uptake, maximal power, systolic blood pressure, diastolic blood pressure (DBP), and maximal heart rate were measured during exercise in order to detect hemodynamic alterations. Patients presenting CRP levels above 3 mg/L were considered CRP-positive. Results: Minimal peripheral oxygen saturation during sleep was significantly higher among nondesaturators (p = 0.03). More desaturators presented CRP > 3 mg/L (p < 0.05). No differences were observed in terms of any variables, However, mean peripheral oxygen saturation during sleep correlated with DBP and maximal inspiratory pressure (p < 0.001 and p = 0.001, respectively). Conclusions: Although nocturnal hypoxemia does not reduce exercise capacity or hand-grip strength in patients with mild/moderate COPD, its effect on maximal exercise DBP seems to depend on the degree of hypoxemia. In addition, there is a positive relationship between maximal inspiratory pressure and mean peripheral oxygen saturation during sleep, as well as evidence of pronounced inflammatory activation in patients with nocturnal hypoxemia.

Keywords: Pulmonary disease, chronic obstructive; Exercise test; Anoxia; Respiratory function tests.

Objective: To translate the London Chest Activity of Daily Living (LCADL) scale into Portuguese and to determine whether this version is reproducible in Brazilian patients with severe chronic obstructive pulmonary disease (COPD). Methods: The LCADL scale was translated into Portuguese and then back-translated into English. This pilot Brazilian Portuguese version was administered to 8 patients with COPD, and possible text-related problems were investigated. The principal problems were discussed with the authors of the original scale, and a final translated version was arrived at. At the study outset, two observers administered this final version (twice in one day) to 31 patients with COPD. One of those observers again administered the scale to the same patients 15-20 days later. At baseline, the patients were submitted to pulmonary function testing and to the six-minute walk test (6MWT). Results: The Brazilian Portuguese version of the LCADL scale demonstrated excellent reproducibility in the total score and in most of the questions, with an inter-rater Cronbach's alpha coefficient of 0.97 (95% CI: 0.89-0.97; p < 0.01) and an intra-rater Cronbach's alpha coefficient of 0.96 (95% CI: 0.83-0.96; p < 0.01). The total score presented a negative correlation with forced expiratory volume in one second in liters (r = −0.49; p < 0.05) and with distance covered on the 6MWT (r = −0.56; p < 0.05). Conclusion: The Brazilian Portuguese version of the LCADL scale is a reliable, reproducible, and valid instrument for evaluating dyspnea during activities of daily living in patients with severe COPD.

Keywords: Activities of daily living; Dyspnea; Diagnostic techniques and procedures; Reproducibility of results.