Which field walking test should be used to assess functional exercise capacity in lung cancer? an observational study Benefits of pulmonary rehabilitation in pediatric asthma Shuttle Walking Test and 6-Minute Walking Test Induce a Similar Cardiorespiratory Performance in Patients Recovering from an Acute Exacerbation of Chronic Obstructive Pulmonary Disease The endurance shuttle walk test: An alternative to the six-minute walk test for the assessment of ambulatory oxygen Comparison between an indoor and an outdoor 6-minute walk test among individuals with chronic obstructive pulmonary disease. Relation of Longitudinal Changes in Quality of Life Assessments to Changes in Functional Capacity in Patients With Heart Failure With and Without Anemia. Six-minute walking versus shuttle walking: responsiveness to bronchodilation in chronic obstructive pulmonary disease Six-minute-walk test in idiopathic pulmonary fibrosis: test validation and minimal clinically important difference. [Reference Equations for the 6-Minute Walk Test in Healthy Individuals.] Impact of neuromuscular electrical stimulation on functional capacity of patients with chronic kidney disease on hemodialysis. Reproducibility of the 6-Minute Walk Test for Ambulatory Oxygen Prescription Repeat six-minute walk tests in patients with chronic heart failure: are they clinically necessary? Submaximal exercise testing in the assessment of interstitial lung disease secondary to systemic sclerosis: reproducibility and correlations of the 6-min walk test Preliminary report of the 6-minute walk test as a predictor of radiation-induced pulmonary toxicity. Group-based Aerobic Interval Training in Patients With Chronic Heart Failure: Norwegian Ullevaal Model Psychological interventions for pediatric chronic pain – The good news and the challenges ahead Course length of 30 metres versus 10 metres has a significant influence on six-minute walk distance in patients with COPD: an experimental crossover study. Determination of exacerbation predictors in patients with COPD in physical therapy - a longitudinal study Updated assessment of the six-minute walk test as predictor of acute radiation-induced pneumonitis. Effect of wearing a dorsiflexion assist orthosis on mobility, perceived fatigue and exertion during the six-minute walk test in people with multiple sclerosis: a randomised cross-over protocol Validity and reliability of the modified shuttle walk test in patients with chronic obstructive pulmonary disease. Six-Minute Walk Test and Cardiopulmonary Exercise Testing in Patients With Chronic Heart Failure: A Comparative Analysis on Clinical and Prognostic Insights Exercise rehabilitation for patients with critical illness: a randomized controlled trial with 12 months of follow-up
Background There is emerging evidence regarding the efficacy of exercise training to improve exercise capacity for individuals with non-small cell lung cancer ( NSCLC ) .  Cardiopulmonary exercise testing ( CPET ) is the gold st and ard measure of exercise capacity ; however this laboratory test has limitations for use in research and clinical practice . Alternative field walking tests are the six-minute walk test ( 6MWT ) , incremental-shuttle walk test ( ISWT ) and endurance-shuttle walk test ( ESWT ) ; however there is limited information about their clinimetric properties in NSCLC . Aims : In NSCLC to determine the 1 ) criterion validity of the 6MWT , ISWT and ESWT against CPET ; 2 ) construct validity of the 6MWT , ISWT and ESWT against measures of function , strength , respiratory function and health-related quality of life ( HRQoL ) ; and 3 ) clinical applicability of the tests . Methods Twenty participants ( 40 % male , mean ± SD age 66.1 ± 6.5 years ) with stage I-IIIb NSCLC completed the 6MWT , ISWT , ESWT and CPET within six months of treatment . Testing order was r and omised . Additional measures included Eastern Cooperative Oncology Group Performance-Status ( ECOG-PS , function ) , respiratory function , h and -grip dynamometry and HRQoL. Correlations and regression analyses were used to assess relationships . Results The ISWT demonstrated criterion validity with a moderate relationship between ISWT distance and CPET peak oxygen consumption ( r = 0.61 , p = 0.007 ) . Relationships between CPET and six minute walk distance ( 6MWD ) ( r = 0.24 , p = 0.329 ) or ESWT time ( r = 0.02 , p = 0.942 ) were poor . Moderate construct validity existed for the 6MWD and respiratory function ( forced vital capacity % predicted r = 0.53 , p = 0.019 ; forced expiratory volume in the first second % predicted r = 0.55 , p = 0.015 ) . There were no relationships between the walking tests and measures of function , strength or HRQoL. The ESWT had a ceiling effect with 18 % reaching maximum time . No floor effects were seen in the tests . The mean ± SD time required to perform the individual 6MWT , ISWT and ESWT was 12.8 ± 2.5 , 14.7 ± 3.7 and 16.3 ± 5.0 min respectively ; in comparison to CPET which was 51.2 ± 12.7 min . Only one assessor was required to perform all field walking tests and no adverse events occurred . Conclusions The ISWT is a promising measure of functional exercise capacity in lung cancer . Findings need to be confirmed in a larger sample prior to translation into practice INTRODUCTION There are limited studies evaluating the role of pulmonary rehabilitation ( PR ) in pediatric asthma . METHODS A retrospective chart review was performed of all pediatric patients with a diagnosis of asthma enrolled in PR . Demographics , medications , and clinical records were review ed . In addition , PFTs , 6-min walk test ( 6MWT ) , and patient/parent symptom and quality of life surveys before and after PR were evaluated . RESULTS A total of 38 patients were enrolled in PR ; 18 ( 47 % ) female and 20 ( 53 % ) male . Mean participant age was 11.33 ± 3.37 ( range 4 - 19 ) years . Twenty-two ( 58 % ) were Caucasian and nine ( 24 % ) African American . Chart review was limited by incomplete data sets for many participants . Following PR , significant improvement was noted in mean 6MWT distance ( 1541 vs 1616 feet , P = 0.05 ) and FEV1 ( 89.9 % of predicted versus 96.4 % , P = 0.04 ) . Survey instruments demonstrated improvement in several clinical factors , however , there was no significant change in weight following PR despite scheduled cardiovascular exercise and dietary counseling . CONCLUSIONS Structured PR for pediatric patients with asthma can improve 6MWT distance and FEV1 as well as subjective measures of SOB and QOL , suggesting a role for PR in the chronic management of pediatric asthma . Further prospect i ve investigation is needed to determine if PR has positive effects on other clinical parameters of asthma control and its overall impact on childhood obesity Background : The incremental shuttle walking test ( SWT ) has recently been proposed as a more valid and reproducible alternative to the conventional 6-min walking test ( 6MWT ) in the evaluation of exercise tolerance in patients with chronic obstructive pulmonary disease ( COPD ) . Objective : To compare the cardiorespiratory performance obtained during two sessions of SWT with that obtained during two sessions of 6MWT . Methods : We examined 18 patients ( forced expiratory volume in 1 s : 48 ± 14 % ) recovering from an acute exacerbation of COPD that had required hospitalization . In the same afternoon , each patient performed two SWT and two 6MWT , with an interval of at least 30 min between each test ; the sequence of the tests was r and omized . Results : Mean walking distance was greater in the second SWT test than in the first SWT . The changes from baseline in systolic blood pressure , heart rate , respiratory rate , oxygen saturation and dyspnea Borg index at the end of the test were similar between the two 6MWT and the two SWT . There was a highly significant correlation between walking distances measured during SWT and during 6MWT ( ρ : 0.85 , p < 0.0005 ) . Neither SWT nor 6MWT correlated with functional data of COPD . Conclusions : SWT , though being considered to be closer to a submaximal exercise test than 6MWT , does not induce a greater cardiorespiratory performance  than 6MWT in patients recovering from acute exacerbation of COPD UK guidelines for domiciliary oxygen have suggested the six-minute walk test or shuttle walk tests as suitable functional measures for the clinical assessment of ambulatory oxygen ( AO ) . To date , there is limited evidence that would support the use of shuttle walk tests as assessment tools for AO . The endurance shuttle walk test ( ESWT ) is used increasingly as an assessment tool within pulmonary rehabilitation ( PR ) but its potential as an investigative test for AO has not been explored . Using the same test for both PR and AO assessment is appealing since it would improve efficiency and act to st and ardise outcome measures in this patient population . The aim of this study was to examine the responsiveness and repeatability of the ESWT to AO and to compare the response with that of the six-minute walk test ( 6MWT ) .  Twenty-three patients with chronic obstructive pulmonary disease ( COPD ) performed , in r and om order , the ESWT and the 6MWT on air and whilst breathing AO . Oxygen saturation and Borg ratings of breathlessness and perceived exertion were recorded . On a third day , eleven patients repeated the ESWT with AO in order to measure repeatability . There was a significantly greater change in the ESWT with oxygen than the change recorded from the 6MWT ( 66 [ 91 ] vs 6 [ 28 ] m respectively ; P < .05 ) . When repeated on a separate day , the mean difference ( 95 % CI ) between distances walked on the ESWT with AO was 0.91 ( -47 , 49 ) m. The ESWT was more responsive than the 6MWT for detecting improvements in walking endurance whilst breathing AO OBJECTIVES To investigate the feasibility of an outdoor 6-minute walk test ( 6MWT ) as a measure of functional status among individuals with chronic obstructive pulmonary disease ( COPD ) , and to examine the relationship between performance on an indoor and an outdoor 6MWT . DESIGN An experimental , repeated- measures crossover design . Subjects were studied on 2 separate days in the same week . Two 6MWTs-one indoors and the other outdoors-were performed on each study day , with a rest in between . The test order was r and omly selected on the first day and reversed on the second day . Outdoor tests were performed on days of moderate weather conditions ( mean temperature + /- st and ard deviation , 21 degrees + /-3 degrees C ; mean wind speed , 15+/-7 km/h ; no precipitation ) and on a flat surface ( sidewalk ) . SETTING  Outpatient rehabilitation program in Ontario . PARTICIPANTS Eighteen subjects with COPD ( 10 men , 8 women ; age , 70+/-8y ) , 5 using supplemental oxygen at rest ( forced expiratory volume in 1s , 1.0+/-0.3L ; 42%+/-8 % of predicted ) . INTERVENTIONS Not applicable . MAIN OUTCOME MEASURES Distance walked in 6 minutes ( in meters ) , duration of rest ( in seconds ) , and change in rate of perceived dyspnea . RESULTS There was no significant effect of setting ( indoors vs outdoors ) on distance walked ( 394+/-86 m vs 398+/-84 m , P=0.4 ) , duration of rest ( 13+/-28s vs 9+/-20s , P=0.4 ) , or change in rate of perceived dyspnea ( 2.3+/-1.7 vs 2.3+/-2.0 , P=0.8 ) . Testing day had no significant effect on walk test performance ( all P>0.1 ) . CONCLUSIONS The results indicate that the 6MWT performed outdoors within reasonable climatic parameters may be reflective of 6MWT performance indoors Clinical status in heart failure is conventionally assessed by the physician 's evaluation , patients ' own perception of their symptoms , quality of life ( QoL ) tools , and a measure of functional capacity . These aspects can be measured with tools such as the New York Heart Association functional class , QoL tools such as the EuropeanQoL-5 dimension , the Kansas City Cardiomyopathy Question naire , patient global assessment ( PGA ) , and by 6-minute walk test ( 6MWT ) , respectively . The ferric carboxymaltose in patients with heart failure and iron deficiency ( FAIR-HF ) trial demonstrated that treatment with intravenous ferric carboxymaltose in iron-deficient patients with symptomatic heart failure with reduced left ventricular function , significantly improved all 5 outcome measures . This analysis assessed the correlations between the longitudinal changes in the measures of clinical status , as measured by QoL tools and the changes in the measures of functional capacity as measured by the 6MWT . This analysis used the data base from the FAIR-HF trial , which r and omized 459 patients with chronic heart failure ( reduced left ventricular ejection fraction ) and iron deficiency , with or without anemia to ferrous carboxymaltose or placebo .  The degree of correlation between QoL tools and the 6MWT was assessed at 4 , 12 , and 24 weeks . The data demonstrate highly significant correlations between QoL and functional capacity , as measured by the 6MWT , at all time points ( p < 0.001 ) . Changes in PGA , Kansas City Cardiomyopathy Question naire , and EuroQoL-5D correlated increasingly over time with changes in 6MWT performance . Interestingly , the strongest correlation at 24 weeks is for the PGA , which is a simple numerical scale ( r = -0.57 , p < 0.001 ) . This analysis provides evidence that QoL assessment show a significant correlation with functional capacity , as measured by the 6MWT . The strength of these correlations increased over time Background : The responsiveness of the endurance shuttle walk to functional changes following bronchodilation has recently been reported . The current literature suggests that the 6 min walking test ( 6MWT ) is less responsive to bronchodilation than the endurance shuttle walk . Aim : To compare bronchodilator-induced changes in exercise performance with the 6MWT and the endurance shuttle walk . Methods : In a r and omised , double-blind , placebo-controlled , crossover trial , 14 patients with chronic obstructive pulmonary disease ( forced expiratory volume in 1 s ( FEV1 ) 50 (8)% predicted ) completed two 6MWTs and two endurance shuttle walks , each preceded by nebulised placebo or 500 μg ipratropium bromide .  Cardiorespiratory parameters were monitored during each walking test with a portable telemetric gas analyser . Quadriceps twitch force was measured by magnetic stimulation of the femoral nerve before and after each walking test . Results : The 6 min walking distance did not change significantly after bronchodilation despite a significant increase in FEV1 of 0.18 ( 0.09 ) litres ( p<0.001 ) . A similar change in FEV1 ( 0.18 ( 0.12 ) litres , p<0.001 ) was associated with a significant improvement in the distance walked on the endurance shuttle walk ( Δdistance ipratropium bromide – placebo = 144 ( 219 ) m , p = 0.03 ) . Quadriceps muscle fatigue was infrequent ( < 15 % of patients ) after both walking tests . Conclusion : The endurance shuttle walk is more responsive than the 6MWT for detecting changes in exercise performance following bronchodilation RATIONALE The 6-minute-walk test ( 6MWT ) is a practical and clinical ly meaningful measure of exercise tolerance with favorable performance characteristics in various cardiac and pulmonary diseases . Performance characteristics in patients with idiopathic pulmonary fibrosis ( IPF ) have not been systematic ally evaluated . OBJECTIVES To assess the reliability , validity , and responsiveness of the 6MWT and estimate the minimal clinical ly important difference ( MCID ) in patients with IPF . METHODS The study population included all subjects completing a 6MWT in a clinical trial evaluating interferon gamma-1b ( n = 822 ) .  Six-minute walk distance ( 6MWD )  and other parameters were measured at baseline and at 24-week intervals using a st and ardized protocol . Parametric and distribution-independent correlation coefficients were used to assess the strength of the relationships between 6MWD and measures of pulmonary function , dyspnea , and health-related quality of life . Both distribution-based and anchor-based methods were used to estimate the MCID . MEASUREMENTS AND MAIN RESULTS Comparison of two proximal measures of 6MWD ( mean interval , 24 d ) demonstrated good reliability ( coefficient = 0.83 ; P < 0.001 ) . 6MWD was weakly correlated with measures of physiologic function and health-related quality of life ; however , values were consistently and significantly lower for patients with the poorest functional status , suggesting good construct validity . Importantly , change in 6MWD was highly predictive of mortality ; a 24-week decline of greater than 50 m was associated with a fourfold increase in risk of death at 1 year ( hazard ratio , 4.27 ; 95 % confidence interval , 2.57- 7.10 ; P < 0.001 ) . The estimated MCID was 24 - 45 m. CONCLUSIONS The 6MWT is a reliable , valid , and responsive measure of disease status and a valid endpoint for clinical trials in IPF The six-minute walk test ( 6MWT ) has been broadly used in clinical setting s. Several reference equations for prediction of the total distance walked during the test ( 6MWD ) are available in literature . The present review aim ed to critically discuss studies , published in Portuguese and English ( LILACS , SCIELO , MEDLINE , PUBMED ) , which evaluated normal values and created reference equations for predicting 6MWD in healthy subjects , comparing them with the results that were recently obtained in Brazilian individuals . Age , sex , weight , height and body mass index were the main demographic and anthropometric features more often correlated with 6MWD . The equations derived from these characteristics were able to explain between 25 and 66 % of the total variability in the 6MWD . Unfortunately , the foreign equations were not applicable to the Brazilian population . Even when the 6MWT was performed following strict st and ardization , the difference in 6MWT performance between foreign and Brazilian individuals remains , indicating the necessity of providing specific reference equations for each population and /or ethnic group . Accordingly , these equations developed in Brazil are probably the most appropriate for interpreting 6MWT performance in Brazilian patients with chronic diseases affecting the exercise capacity . Future studies are necessary with larger sample sizes ( e.g. multicentric ones ) and r and omized design for the reference values of the 6MWD to be considered reliable Introduction Literature shows that patients undergoing hemodialysis present poor physical conditioning and low tolerance to exercise . They may also suffer from respiratory dysfunctions . The purpose of this study was to evaluate the effects of neuromuscular electrical stimulation on pulmonary function and functional capacity of patients with chronic kidney disease on hemodialysis . Methods Forty adult patients with chronic kidney disease on hemodialysis were prospect ively studied and r and omized into two groups ( control n = 20 and treatment n = 20 ) . The treatment group underwent bilateral femoral quadriceps muscles electrical stimulation for 30 minutes during hemodialysis , three times per week , for two months . The patients were evaluated by pulmonary function test , maximum respiratory pressures , maximum one-repetition test , and six-minute walk test ( 6MWT ) , before and after the treatment protocol . Results The treatment group presented increased maximum inspiratory ( MIP ) ( p = 0.02 ) and expiratory pressures ( MEP ) ( p < 0.0001 ) , muscular strength in maximum one-repetition test ( p < 0.001 ) , and distance covered in the 6MWT ( p = 0.03 ) , and decreased systolic blood pressure ( p < 0.001 ) and respiratory frequency ( p < 0.001 ) when compared with the control group . Conclusion Electrical neuromuscular stimulation had a positive impact on pulmonary function and functional capacity , leading to better physical performance in patients on hemodialysis Background : Ambulatory oxygen is frequently prescribed for patients with chronic obstructive pulmonary disease ( COPD ) who have oxygen desaturation ≤88 % during exercise . The 6-min walk test ( 6MWT ) with continuous pulse oximetry monitoring is a common method to document this oxygen desaturation , but the reproducibility of this test in determining the need for ambulatory oxygen in patients with COPD is not well documented . Objective : The aim of this study was to establish the reproducibility of the 6MWT in determining the need for ambulatory oxygen prescription in stable COPD patients using the Centers for Medicare and Medicaid ( CMS ) criteria for ambulatory oxygen prescription . Methods : The study was design ed as a prospect i ve observational study in an academic health center and associated pulmonary rehabilitation program . Eighty-eight COPD patients referred to pulmonary rehabilitation underwent continuous pulse oximetry while performing st and ard 6MWT on 3 separate days . Results : Fifty-one ( 58 % ) of these patients desaturated by continuous pulse oximetry to an SpO2 ≤88 % on a least one of the 6MWTs . Only 26 patients ( 30 % ) demonstrated consistency in meeting the criteria for ambulatory oxygen set forth by the CMS on all three 6MWT with a κ statistic of 0.62 . The percent agreement between 6MWTs for ambulatory oxygen prescription was 72 % and the paired observation was 51 % . Conclusions : The 6MWT distance is simple and widely used as a consistent measure of functional capacity in patients with COPD ; however , the 6MWT oxygen saturation has only modest reproducibility in determining the need for ambulatory oxygen in stable COPD patients undergoing pulmonary rehabilitation Background : Owing to a reported learning effect in patients with chronic cardiopulmonary disease , performance of at least two six-minute walk tests ( 6MWT ) are recommended as st and ard practice . Patients with chronic heart failure ( CHF ) are typically elderly and frail and it is unknown whether current guidelines are practical in a clinical setting . Aims : The aim of this study was to determine whether repeat performance of 6MWTs in patients with CHF is related to between-test interval or baseline performance . Methods : This was a multisite observational study enrolling participants entering into heart failure rehabilitation programmes . Participants performed two 6MWTs with r and omly allocated inter-test intervals between 15 and 90 minutes . Distance walked in the second test was compared with the first test using a paired t test . Results : Eighty-eight participants ( 45 females , age 65 ± 14 years ) with stable CHF were enrolled . Mean distance walked increased from 301 metres in test 1 to 313 metres in test 2 ( p < 0.001 ) . No significant change was recorded between test 1 and test 2 for those whose baseline distance was < 300 metres . The interval between tests had no significant effect on the distance walked . Conclusion : The change in 6MWT distance was significantly associated with better baseline performance but not with the interval between tests Background : The 6-min walk test ( 6MWT ) is increasingly used as an outcome measure in interstitial lung disease ( ILD ) . Aim : To evaluate the usefulness of the 6MWT in a cohort of patients with ILD secondary to systemic sclerosis ( SSc ) and to correlate with established physiological parameters . Methods : 163 patients with SSc-ILD were recruited for a multicentre , r and omised , double-blind clinical trial . Available data at protocol screening included repeated 6MWTs , pulmonary function testing with diffusing capacity , Doppler echocardiography and high-resolution computed tomography of the thorax . Borg Dyspnoea Index was evaluated before and after 6MWT . Results : Mean ( st and ard deviation ( SD ) ) distance walked during walk test 1 was 396.6 ( 84.55 ) m compared with 399.5 ( 86.28 ) m at walk test 2 . The within-subject , intertest correlation as determined by Pearson ’s correlation coefficient testing was 0.95 ( p<0.001 ) . However , only weak correlations of 6MWT with percentage forced vital capacity and the Borg Dyspnoea Index were observed , and no correlation was observed with percentage diffusing capacity . Conclusion : These data confirm the high reproducibility of the  6MWT in patients with SSc-ILD and therefore the validity of the test in this cohort . The lack of correlation of 6MWT with st and ard physiological parameters of ILD suggests a multifactorial basis for limited exercise capacity in patients with SSc and calls into question the utility of the 6MWT as a measure of outcome in future studies on SSc-ILD PURPOSE To assess the 6-minute walk test ( 6MWT ) as a predictor of  radiation therapy-induced lung injury ( RTLI ) .  METHODS AND MATERIAL S The 6MWT is a simple , economical , and reproducible test that measures both how far a person can walk in 6 min and any associated changes in vital signs . As part of a prospect i ve trial to study RTLI , a pre-RT 6MWT was performed in 41 patients . The predictive capacities of pre-RT 6MWT , forced expiratory volume in 1 s ( FEV1 ) , and single-breath diffusing capacity for carbon monoxide ( DLCO ) for the development of RTLI were assessed with receiver operating curve ( ROC ) techniques . To evaluate the 6MWT , alone or with mean lung dose ( MLD ) of radiation , as a predictor of RTLI , the rates of RTLI in patient subgroups defined by 6MWT results were compared by using Fisher 's exact test . RESULTS Thirty-one patients with > or =3 months ' follow-up were evaluable . The median baseline 6MWT result was 1400 ft . Of 31 patients , 7 developed Grade > or = 2 RTLI . Of 15 patients with an MLD > 18 Gy ( the median ) , 5 developed RTLI , compared with 2 of 16 with MLD < or = 18 Gy ( p = 0.22 ) . Among those with an MLD < or = 18 Gy , the RTLI rates were 0 of 8 and 2 of 8 for 6MWT results > or = 1400 ft or < 1400 ft , respectively , p = 0.46 . The ROC area under the curve for individual metrics was as follows : FEV1 0.66 , MLD 0.70 , DLCO 0.61 , and 6MWT 0.47 . Combining FEV1 with 6MWT increased the ROC to 0.71 , suggesting that the ratio might be a better predictor than the individual values . Patients with a high 6MWT/FEV1 ratio had a lower rate of RTLI than those with a relatively low ratio . CONCLUSIONS The 6MWT might provide prognostic information beyond pulmonary function tests and dosimetric parameters in predicting RTLI . Additional work is needed to better assess the utility of these functional metrics Background and Purpose : The purpose of this case report is to describe the responses of 4 patients with chronic heart failure ( CHF ) to a novel rehabilitation program : a group-based , high-intensity , interval-training program that includes aerobic , resistance , flexibility , and balance activities . Case Descriptions : Four patients ( 55–71 years of age ) with CHF ( New York Heart Association class III ) participated in the rehabilitation program twice per week for 16 weeks . Outcome measures included a 6-minute walk test ( 6MWT ) , a cycle ergometer test ( aerobic capacity ) , and a quality -of-life question naire . Outcomes : Patients 1 , 2 , and 3 increased their aerobic capacity ( 17 % , 25 % , and 52 % , respectively ) . Patient 4 did not complete the cycle ergometer test because of limitations associated with his pacemaker . All patients increased their 6MWT distance ( 117 , 66 , 135 , and 143 m for patients 1 , 2 , 3 , and 4 , respectively ) . No adverse events were reported . Discussion : The Norwegian Ullevaal Model of cardiac rehabilitation is a novel high-intensity , interval-training program . The 4 patients with CHF in this case series who participated in this program experienced improvements in physical capacity and quality of life and had no adverse events . These results are consistent with recent evidence supporting the efficacy of high-intensity interval training in people with CHF . R and omized clinical trials are needed to evaluate the clinical efficacy of this group-based , high-intensity , aerobic interval-training program for patients with CHF In a 2002 systematic review of pediatric clinical trials Eccleston et al. [ 1 ] found that psychological therapies had a significant effect on pain reduction . Although that review sought to include all pain conditions , the available studies at the time focused almost exclusively on treatment of pediatric headache . In recent years , r and omized clinical trials ( RCTs ) have been published on other pediatric pain conditions , including abdominal pain and fibromyalgia . In addition , effects of psychological therapies on clinical outcomes beyond pain reduction , such as functional disability and emotional distress were examined . In this issue of Pain , Palermo et al. [ 4 ] present a timely meta-analytic review paper that reflects on these new developments QUESTIONS Do patients with chronic obstructive pulmonary disease ( COPD ) achieve a different distance on the six minute walk test ( 6MWT ) conducted on a 10 m course versus on a 30 m course ? When assessing the distance on a 6MWT conducted on a 10 m course , is it valid to use existing reference equations that were generated on longer courses ? DESIGN A r and omised double-crossover experimental study . PARTICIPANTS Forty-five patients with COPD in primary physiotherapy care . INTERVENTION All patients performed a 6MWT twice over a 10 m course and twice over a 30 m course . The 6MWTs were performed in accordance with the American Thoracic Society guidelines . OUTCOME MEASURES 6MWD was assessed and predicted distance was calculated based on a range of reference equations . RESULTS The 6MWD on the 10 m course was 49.5 m shorter than on the 30 m course , which was statistically significant ( 95 % CI 39.4 to 59.6 ) . By using existing reference equations for a 6MWT conducted on the 10 m course , the predicted distance is highly overestimated ( with a range of 30 % to 33 % ) and the average distance as a percentage of the predicted value is 8%pred lower compared to a 6MWT conducted on the 30 m course , result ing in a worse representation of a COPD patient 's functional exercise capacity . CONCLUSION This study shows that the impact of course length on the 6MWD and on the use of reference equations in patients with COPD is substantial and clinical ly relevant ( based on the most conservative published minimum clinical ly important difference ) . Therefore , existing reference equations established for a 6MWT conducted over a 30 m ( or longer ) course can not be applied to predict the distance achieved on the 6MWT on a 10 m course , which is frequently used in primary care physiotherapy practice s for patients with COPD Background Chronic obstructive pulmonary disease ( COPD ) typically presents the characteristic clinical condition of exacerbation , with more intense symptoms associated with greater functional loss and consequently lower chances of patient survival . Objectives This study sought to determine the predictors of exacerbation , alone or in combination , in patients with chronic obstructive pulmonary disease ( COPD ) who received physical therapeutic treatment over 6 months . Method This was an observational , longitudinal and prospect i ve study in which 63 COPD patients residing within the municipality of São Carlos , SP , Brazil were evaluated . These patients had COPD stages II and III and were entered into a physical therapy program , consisting of 3 periods of assessment over 6 months . We evaluated the occurrence of acute exacerbation as well as the patients ' body mass index ( BMI ) , fat-free mass ( FFM ) , fat-free mass index , forced expiratory volume in 1 second ( FEV1 ) , dyspnea , distance walked ( DW ) in the 6-minute walk test ( 6MWT ) and h and grip strength . Results When applying Cox setting s with each covariate separately , the results revealed 5 % significance only for the DW in the 6MWT , which demonstrated an interaction between BMI and FFM . Comparison of the 3 periods of assessment across the covariates measured showed a significant difference only for the DW between evaluations in the 3rd and 6th months . Conclusion Upon analyzing the predictors of risk over 6 months of follow-up in patients with COPD , we found that the DW in the 6MWT was associated with the risk of exacerbation , although this risk also depended on the covariates BMI and FFM PURPOSE To assess the utility of the 6-minute walk test ( 6MWT ) as a predictor of  symptomatic radiation-induced pneumonitis ( RP ) .  METHODS As part of a prospect i ve trial to study radiation-induced lung injury , 53 patients receiving thoracic radiotherapy ( RT ) underwent a pre-RT 6MWT , pulmonary function tests ( PFTs ) , and had > or=3-month follow-up for prospect i ve assessment of Grade 2 or worse RP ( requiring medications or worse ) . Dosimetric parameters ( e.g. , the percentage of lung receiving > or=30 Gy ) were extracted from the lung dose-volume histogram . The correlations between the 6MWT and PFT results were assessed using Pearson 's correlation . The receiver operating characteristic technique was used in patient subgroups to evaluate the predictive capacities for RP of the dosimetric parameters , 6MWT results , and PFT results , or the combination ( using discriminant analysis ) of all three metrics . ROCKIT software was used to compare the receiver operating characteristic areas between each predictive model . The association of the decline in 6MWT with the development of RP was evaluated using Fisher 's exact test . RESULTS The pre-RT PFT and 6MWT results correlated weakly ( r = 0.44 - 0.57 , p < or= 0.001 ) , suggesting that they measure somewhat different physiologic functions . Of the 53 patients , 9 ( 17 % ) developed RP . The dose-volume histogram-based dosimetric parameters were the best single-metric model for predicting RP ( e.g. , percentage of lung receiving > or=30 Gy , receiver operating characteristic area 0.73 , p = 0.03 ) . Including the PFT or 6MWT results with the percentage of lung receiving > or=30 Gy did not improve the predictions . The predictive abilities of dosimetric-based models improved when the analysis was restricted to those patients whose tumors were not causing regional lung dysfunction . No correlation was found between the decline in the 6MWT result and the RP rate ( p = 0.6 ) . CONCLUSION Although the PFTs and 6MWT are related to each other , the correlation coefficients were weak , suggesting that they could be measuring different physiologic functions . In the present data set , the addition of the PFTs or 6MWT did not increase the ability of the dosimetric parameters to predict for acute symptomatic RP . Additional work is needed to better underst and the interaction among the PFT results , exercise tolerance ( 6MWT ) , and the risk of RT-induced  lung dysfunction Background Fatigue in combination with gait and balance impairments can severely limit daily activities in people with multiple sclerosis ( PWMS ) . Generalised fatigue has a major impact on walking ability , with moderately disabled PWMS experiencing difficulty in walking extended distances . Localised motor fatigue in the ankle dorsiflexors can lead to foot drop , further reducing functional ambulation . The aim of this study is to evaluate the effect of a simple dynamic dorsiflexion assist orthosis on walking-induced fatigue , gait , balance and functional mobility in PWMS . Methods A r and omised cross-over trial will be conducted with 40 community dwelling PWMS with mild to moderate mobility disability . Participants will initially be screened for disease severity , balance , strength , depression and fatigue at the South Australian Motion Analysis Centre . On two non-consecutive occasions , within two weeks , participants will undergo either the 6-minute walk test ( 6MWT ) or the 6MWT while wearing a dorsiflexion ankle orthosis ( with a r and omised condition order ) . Distance walked , perceived exertion , perceived fatigue and the physiological cost of walking ( the primary outcome measures ) will be compared between the two walking conditions . Additional pre- and post-6MWT assessment s for the two conditions will include tests of strength , reaction time , gait and balance . Discussion This study will increase our underst and ing of motor fatigue on gait and balance control in PWMS and eluci date the effect of a Dynamic Ankle Orthosis on fatigue-related balance and gait in PWMS . It will also examine relationships between mobility and balance performance with perceived fatigue levels in this group . Trial Registration OBJECTIVES ( 1 ) To examine the concurrent criterion validity of the modified shuttle walk test ( MSWT ) by using the 6- ( 6MWT ) and 12-minute walk test ( 12MWT ) , ( 2 ) to examine the concurrent criterion validity of the estimated maximum oxygen uptake ( Vo2max ) of the MSWT with actual Vo2max , and ( 3 ) to determine test-retest reliability of the MSWT in patients with chronic obstructive pulmonary disease ( COPD ) . DESIGN Validation study . SETTING Outpatient pulmonary rehabilitation program . PARTICIPANTS Thirty clinical ly stable adults with COPD . INTERVENTIONS Not applicable . MAIN OUTCOME MEASURES Subjects were r and omly assigned to receive either the 6MWT and 12MWT or the MSWT first . The MSWT was repeated 1 week later ( N = 30 ) . Estimated Vo2max was calculated , and actual Vo2max was conducted by using the Jones test . Validity of the MSWT was assessed by comparing endurance scores and Vo2max with results from the 6MWT and 12MWT and Jones test , respectively . RESULTS There was a moderately high correlation between the  MSWT  and the 6MWT and 12MWT at initial testing ( .82 and .74 , respectively ) . Correlation between estimated and actual Vo2max was r equal to .68 . Test-retest reliability for the entire sample was high ( intraclass correlation coefficient , .88 ) . Results remained quite stable across severity , age , and sex subgroups . CONCLUSIONS The MSWT is a st and ardized externally paced submaximal endurance walking test . The results indicate that the MSWT has high concurrent validity and test-retest reliability for patients with COPD Background —The six-minute walk test ( 6MWT ) and cardiopulmonary exercise testing ( CPET ) are the 2 testing modalities most broadly used for assessing functional limitation in patients with heart failure ( HF ) . A comprehensive comparison on clinical and prognostic validity of the 2 techniques has not been performed and is the aim of the present investigation . Methods and Results —Two hundred fifty-three patients diagnosed with systolic ( n=211 ) or diastolic ( n=42 ) HF ( age : 61.9±10.1 years ; New York Heart Association Class : 2.2±0.78 ) underwent a 6MWT and a symptom-limited CPET evaluation and were prospect ively followed up . During the 4-year tracking period , there were 43 cardiac-related deaths with an annual cardiac mortality rate of 8.7 % . The 6MWT distance correlated with CPET-derived variables ( ie , peak Vo2 , Vo2 at anaerobic threshold , and Ve/Vco2 slope ) and was significantly reduced in proportion with lower peak Vo2 and higher Ve/Vco2 slope classes and presence of an exercise oscillatory breathing ( EOB ) pattern ( P<0.01 ) . However , no significant differences were observed in distance covered between survivors and nonsurvivors ( 353.2±95.8 m versus 338.5±76.4 m ; P = NS ) . At univariate and multivariate Cox proportional analyses , the association of the 6MWT distance with survival was not significant either as a continuous or dicotomized variable ( ≤300 m ) . Conversely , CPET-derived variables emerged as prognostic with the strongest association found for EOB ( systolic HF ) and Ve/Vco2 slope ( entire population with HF and patients with a 6MWT≤300 m ) . Conclusions —The 6MWT is confirmed to be a simple and reliable first-line test for quantification of exercise intolerance in patients with HF . However , there is no supportive evidence for its use as a prognostic marker in alternative to or in conjunction with CPET-derived variables Introduction The purpose of this trial was to investigate the effectiveness of an exercise rehabilitation program commencing during ICU admission and continuing into the outpatient setting compared with usual care on physical function and health-related quality of life in ICU survivors . Methods We conducted a single-center , assessor-blinded , r and omized controlled trial . One hundred and fifty participants were stratified and r and omized to receive usual care or intervention if they were in the ICU for 5 days or more and had no permanent neurological insult . The intervention group received intensive exercises in the ICU and the ward and as out patients . Participants were assessed at recruitment , ICU admission , hospital discharge and at 3- , 6- and 12-month follow-up . Physical function was evaluated using the Six-Minute Walk Test ( 6MWT ) ( primary outcome ) , the Timed Up and Go Test and the Physical Function in ICU Test . Patient-reported outcomes were measured using the Short Form 36 Health Survey , version 2 ( SF-36v2 ) and Assessment of Quality of Life ( AQoL ) Instrument . Data were analyzed using mixed models . Results The a priori enrollment goal was not reached . There were no between-group differences in demographic and hospital data , including acuity and length of acute hospital stay ( LOS ) ( Acute Physiology and Chronic Health Evaluation II score : 21 vs 19 ; hospital LOS : 20 vs 24 days ) . No significant differences were found for the primary outcome of 6MWT or any other outcomes at 12 months after ICU discharge . However , exploratory analyses showed the rate of change over time and mean between-group differences in 6MWT from first assessment were greater in the intervention group . Conclusions Further research examining the trajectory of improvement with rehabilitation is warranted in this population .Trial registration The trial was registered with the Australian New Zeal and Clinical Trials Registry ACTRN12605000776606
Limited evidence to strong evidence was found for reliability in various chronic conditions .
Little evidence was available for responsiveness and measurement error .
Studies showed large variability in test procedures despite existing guidelines for the performance of the 6MWT .
Evidence for measurement properties of the 6MWT  varies largely among chronic pediatric conditions .
BACKGROUND The Six-Minute Walk Test ( 6MWT ) is increasingly being used as a functional outcome measure for chronic pediatric conditions .
Knowledge about its measurement properties is needed to determine whether it is an appropriate test to use .
PURPOSE The purpose of this study was to systematic ally review all published clinimetric studies on the 6MWT in chronic pediatric conditions .