Reliability, Sensitivity and Validity of the 6 Minute Step Test in Chronic Obstructive Pulmonary Disease (COPD) Patients

Reliability, Sensitivity and Validity of the 6 Minute Step Test in Chronic Obstructive Pulmonary Disease (COPD) Patients

Evaluation of Reliability, Sensitivity and Validity of the Six Minute Step Test in Patients With Chronic Obstructive Pulmonary Disease and Its Relation With Predictors Markers of Risk of Death

Chronic Obstructive Pulmonary Disease (COPD) leads to a reduction in exercise capacity that affects the quality of life and increases mortality of these patients. So, exercise tests are considered as an essential component of the clinical evaluation of the patients with COPD. The objective of this study is to evaluate the reproducibility sensitivity and validity of the Six Minute Step Test (6MST) in patients with COPD and in health volunteers, and verify its relation with the "Body-Mass Index, Airways Obstruction, Dyspnea and Exercise Capacity" Index (BODE). This Observational, Transversal, Prospective study will be conducted in the "Special Unit of Respiratory Physiotherapy", of the "Federal University of São Carlos". To participate in this study, 120 subjects, both gender, will be invited and will be allocated in five groups: Group I (30 healthy young subjects of 17 to 27 years old), Group II (30 healthy elderly individuals of 60 to 75 years old), and patients COPD, 60 to 80 years old, with mild, moderate, severe and very severe obstruction determined by the forced expiratory volume in one second (FEV1) by forced vital capacity (FVC) relation "FEV1/FVC" <70% and FEV1 in predict percentage < 80% composing the Group III (20 COPD patients in GOLD stage I), Group IV (20 COPD patients in GOLD stage II) and Group V (20 patients COPD stages III and IV). All subjects will be submitted to body composition and anthropometric assessment, pulmonary function test, three 6-minutes walk test (6MWT) and three 6MST. Furthermore, the patients of the groups III, IV and V will answer the Modified Medical Research Council (mMRC) scale, and BODE index will be calculated to each of them.

This test will be conducted by the "Rater 1", the patient will step up and down a 20cm step during six minute. The performance will be evaluated by the number of the steps.

This test will be conducted by the "Rater 1", the patient will step up and down a 20cm step during six minutes. The performance will be evaluated by the number of the climbs.

This test will be conducted by the "Rater 2", the patient will step up and down a 20cm step during six minutes. The performance will be evaluated by the number of the climbs.

On the third day of evaluation, seven days after the first day of evaluation. Since it was performed in the same day of the third 6MWT, the choice of the first test was random, and there was a 30 minute interval between them.

This test will be conducted by the "Rater 1", the subject will walk as far as it can in a 30m corridor during 6 minutes. The performance will be the distance (meters)that it walk.

This test will be conducted by the "Rater 1", the subject will walk as far as it can in a 30m corridor during 6 minutes. The performance will be the distance (meters)that it walk.

This test will be conducted by the "Rater 2", the subject will walk as far as it can in a 30m corridor during 6 minutes. The performance will be the distance (meters)that it walk.

On the third day of evaluation, seven days after the first day of evaluation. Since it was performed in the same day of the third 6MST, the choice of the first test was random, and there was a 30 minute interval between them.

It was evaluated only in the COPD patients. BODE index is a prognostic index used in COPD patients, it is a 0-10 scale, where lower values means better prognostic. It is composed by other commonly used evaluations tools in COPD, Forced Expiratory Volume in the First second (from spirometry); classification in the scale ranging from 0-3, Body-mass index, classification in the scale ranging from 0-1; Six-minute walk test distance, classification in the scale ranging from 0-3 and referred dyspnea, classification in the scale ranging from 0-3. It was only used the total score (0-10)

This test was conducted by the "Rater 1", the subject walked as far as it could in a 30m corridor during 6 minutes. The Exertion Perception will be evaluated using BORG scale. This scale is a self-reported scale, which range from 0 to 10, where 0 means none exertion perception and 10 means very intense exertion perception (the highest the patient has ever felt). Lower values means that the patient feel less discomfort.

This test will be conducted by the "Rater 1", the subject will walk as far as it can in a 30m corridor during 6 minutes. The Exertion Perception will be evaluated using BORG scale. This scale is a self-reported scale, which range from 0 to 10, where 0 means none exertion perception and 10 means very intense exertion perception (the highest the patient has ever felt). Lower values means that the patient feel less discomfort.

This test will be conducted by the "Rater 2", the subject will walk as far as it can in a 30m corridor during 6 minutes. The Exertion Perception will be evaluated using BORG scale. This scale is a self-reported scale, which range from 0 to 10, where 0 means none exertion perception and 10 means very intense exertion perception (the highest the patient has ever felt). Lower values means that the patient feel less discomfort.

On the third day of evaluation, seven days after the first day of evaluation. Since it was performed in the same day of the third 6MST, the choice of the first test was random, and there was a 30 minute interval between them.

This test will be conducted by the "Rater 1", the patient will step up and down one 20cm step during six minute. The Exertion Perception will be evaluated using BORG scale. This scale is a self-reported scale, which range from 0 to 10, where 0 means none exertion perception and 10 means very intense exertion perception (the highest the patient has ever felt). Lower values means that the patient feel less discomfort.

This test will be conducted by the "Rater 1", the patient will step up and down one 20cm step during six minute.The Exertion Perception will be evaluated using BORG scale. This scale is a self-reported scale, which range from 0 to 10, where 0 means none exertion perception and 10 means very intense exertion perception (the highest the patient has ever felt). Lower values means that the patient feel less discomfort.

This test will be conducted by the "Rater 2", the patient will step up down one 20cm step during six minute. The Exertion Perception will be evaluated using BORG scale. This scale is a self-reported scale, which range from 0 to 10, where 0 means none exertion perception and 10 means very intense exertion perception (the highest the patient has ever felt). Lower values means that the patient feel less discomfort.

On the third day of evaluation, seven days after the first day of evaluation. Since it was performed in the same day of the third 6MWT, the choice of the first test was random, and there was a 30 minute interval between them.

This test will be conducted by the "Rater 1", the subject will walk as far as it can in a 30m corridor during 6 minutes. It will be evaluated by a pulse oxymeter.

This test will be conducted by the "Rater 1", the subject will walk as far as it can in a 30m corridor during 6 minutes. It will be evaluated by a pulse oxymeter.

This test will be conducted by the "Rater 2", the subject will walk as far as it can in a 30m corridor during 6 minutes. It will be evaluated by a pulse oxymeter.

On the third day of evaluation, seven days after the first day of evaluation. Since it was performed in the same day of the third 6MST, the choice of the first test was random, and there was a 30 minute interval between them.

This test will be conducted by the "Rater 1", the patient will step up and down one 20cm step during six minute. It will be evaluated by a pulse oxymeter.

This test will be conducted by the "Rater 1", the patient will step up and down one 20cm step during six minute. It will be evaluated by a pulse oxymeter .

This test will be conducted by the "Rater 2", the patient will step up and down one 20cm step during six minute. It will be evaluated by a pulse oxymeter.

On the third day of evaluation, seven days after the first day of evaluation. Since it was performed in the same day of the third 6MWT, the choice of the first test was random, and there was a 30 minute interval between them.

This test will be conducted by the "Rater 1", the subject will walk as far as it can in a 30m corridor during 6 minutes. It will be evaluated by a cardio monitor.

This test will be conducted by the "Rater 1", the subject will walk as far as it can in a 30m corridor during 6 minutes. It will be evaluated by a cardio monitor at rest and every two minutes of the test.

This test will be conducted by the "Rater 2", the subject will walk as far as it can in a 30m corridor during 6 minutes. It will be evaluated by a cardio monitor.

On the third day of evaluation, seven days after the first day of evaluation. Since it was performed in the same day of the third 6MST, the choice of the first test was random, and there was a 30 minute interval between them.

This test will be conducted by the "Rater 1", the patient will step up and down a 20cm step during six minute. It will be evaluated by a cardio monitor.

This test will be conducted by the "Rater 1", the patient will step up and down a 20cm step during six minute. It will be evaluated by a cardio monitor.

This test will be conducted by the "Rater 2", the patient will step up and down a 20cm step during six minute. It will be evaluated by a cardio monitor.

On the third day of evaluation, seven days after the first day of evaluation. Since it was performed in the same day of the third 6MWT, the choice of the first test was random, and there was a 30 minute interval between them.

Inclusion Criteria: Young and elderly healthy subjects presented pulmonary function within the normal range, confirmed by spirometry Patients with clinical and spirometric diagnosis of COPD Exclusion Criteria: Lung disease exacerbated Decompensated heart disease Rheumatic, neurological or orthopedic disease, preventing them from doing the tests by limiting the exercise Peripheral oxygen saturation < 80% without physical effort Subjects who does not complete the first day of evaluation

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