Accuracy of six minute walk test, stair test and spirometry using maximal oxygen uptake as gold standard

Abstract

PURPOSE: To assess the accuracy of the variables stair climbing time (SCt), stair climbing power (SCP), six-minute walk test distance (6MWT), and forced expiratory volume in 1 second (FEV1) using maximal oxygen uptake on exercise (VO2max) as the gold standard. METHODS: Tests were performed in 51 patients. FEV1 was measured by spirometry and 6MWT was performed in a flat 120-m corridor. Stair climbing test was performed on a 6-flight stairway to obtain SCt and SCP. VO2max was measured by ergospirometry, using the Balke protocol. Pearson's linear correlation and p values were calculated between VO2max and the other variables tested. For accuracy calculations, variable cutoff points were obtained through receiver operating characteristic (ROC) curves, dividing individuals into normal or unhealthy. Kappa statistic was used to calculate concordance. RESULTS: Accuracy was: SCt - 86%, 6MWT - 80%, SCP - 71%, FEV1(L) - 67%, FEV1(%) - 63%. SCt and 6MWT showed 93.5% sensitivity when combined in parallel, and 96.4% specificity in series. CONCLUSION: SCt presented the best accuracy. SCt and 6MWT combined showed nearly 100% sensitivity or specificity. Thus, these simple exercise tests should be more routinely used, especially when an ergospirometer is not available to measure VO2max.

Avaliação pré-operatória da força muscular respiratória, da função pulmonar e da capacidade funcional de pacientes submetidos a ressecção pulmonar

“…O TC6 possui boa correlação com o VO 2 máx obtido de forma direta pelo teste cardiopulmonar, considerado como padrão-ouro 21 .…”

Surgical risk tests related to cardiopulmonary postoperative complications: comparison between upper abdominal and thoracic surgery

“…SCT was carried out in a six flights staircase in the shade, 12 steps each flight in a total of 12.16 m height, as standardized by Cataneo and Cataneo 11 . The time in seconds was taken in the end of the staircase ascent and was named time of stair climbing test (tSCT) and the power (P) in watts (w) was calculated using the classic formula 11 .…”

“…Exercise tests can be those of maximal effort such as ergospirometry that measures the oxygen consumption (VO 2 ) 5 or submaximal effort such as stair-climbing test (SCT) [6][7][8][9][10][11][12][13][14][15] and six-minute walk test (6MWT) 9,16 .…”

Cardiorespiratory evaluation in pre and post operative moments of laparoscopic cholecystectomy

“…Still, by the end of the test, it was applied a classification scale for the subjective perception concerning the level of effort (Borg's effort perception index 13 ). SCT was performed in the shadow according to Cataneo et al 14 …”

“…Prior studies 14,15 showed that if the patient is able to walk 500 meters or more in the 6MWT or takes 40 seconds or less to climb up a 12m ladder, it is most likely that his VO 2 is above 25mL/Kg/min, which makes him a patient of low risk for complications after toracic and upper abdomen surgeries. The subjects included in the present study showed a mean value for 6MWT at PRE that was about 500 meters and the SCt of 48 seconds, which proves their good performance at PRE.…”