Universidade Nove de Julho, Rua Vergueiro 235, Sao Paulo, SP 01504-000, Brazil.
Hospital Israelita Albert Einstein, Sao Paulo, SP, Brazil.
J Vasc Nurs. 2021 Jun;39(2):33-38. doi: 10.1016/j.jvn.2021.02.004. Epub 2021 Mar 19.
Although 2-min step test (2MST) has been useful in general population, no study has investigated its validity in patients with peripheral artery disease (PAD).
To analyze the validity and reliability of the 2MST in patients with PAD and claudication symptoms.
Twenty-four patients with PAD and claudication symptoms were recruited and performed the 2MST comparing it to the six-minute walk test (6MWT). Test performance, step indicators, and heart rate were measured during the test. Validity was verified using Pearson correlation between the performance of 2MST (number of steps) and 6MWT (distance and number of steps). The reliability was analyzed by the intraclass correlation coefficient and by the limits of agreement of Bland and Altman.
A similar performance was observed between the two 2MST (65 ± 10 steps vs. 66 ± 10 steps, p = 0.43) with a significant intraclass coefficient correlation of 0.945. The bias between tests was of 0.79 steps with the limits of agreement between -9.6 and 11.2 steps. The 90% minimum detectable difference was 3.2 steps. The number of steps in 2MST was significantly correlated with the number of steps in 6MWT (r = 0.55, p<0.01). However, the number of steps in 2MST did not correlate with distance in the 6MWT (r = 0.26, p = 0.23). The peak heart rate was lower in 2MST compared to 6MWT (p<0.05).
The 2MST present adequate reliability and validity in patients with symptomatic PAD.
虽然 2 分钟踏步测试（2MST）在一般人群中很有用，但尚无研究调查其在有外周动脉疾病（PAD）症状的患者中的有效性。
分析 2MST 在有 PAD 和跛行症状的患者中的有效性和可靠性。
招募了 24 名有 PAD 和跛行症状的患者，并让他们进行 2MST，同时将其与 6 分钟步行测试（6MWT）进行比较。测试过程中测量了测试表现、踏步指标和心率。使用 2MST（步数）与 6MWT（距离和步数）之间的 Pearson 相关性验证有效性。通过组内相关系数和 Bland 和 Altman 的一致性界限分析可靠性。
两种 2MST 的表现相似（65±10 步与 66±10 步，p=0.43），组内相关系数的相关性非常高，为 0.945。两种测试之间的偏差为 0.79 步，一致性界限在-9.6 至 11.2 步之间。90%最小可检测差异为 3.2 步。2MST 的步数与 6MWT 的步数显著相关（r=0.55，p<0.01）。然而，2MST 的步数与 6MWT 的距离不相关（r=0.26，p=0.23）。与 6MWT 相比，2MST 的峰值心率较低（p<0.05）。
2MST 在有症状的 PAD 患者中具有足够的可靠性和有效性。
