Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark.
Department of Physiotherapy and Occupational Therapy, Næstved-Slagelse-Ringsted Hospitals, Region Zealand, Denmark.
J Geriatr Phys Ther. 2021;44(3):144-152. doi: 10.1519/JPT.0000000000000266.
Some uncertainty persists regarding the reproducibility of the recommended core set of performance-based tests, as well as common muscle function tests, when applied in individuals with knee osteoarthritis (KOA). The purpose of this study was to investigate the intrarater reliability and agreement of the recommended core set of performance-based tests and common muscle function tests in KOA.
Participants (N=40) with radiographic and/or symptomatic KOA were evaluated twice with a 3-day interval between test sessions using the following tests: Leg extensor (LE) maximal muscle power measured in a Nottingham Power Rig; knee extensor (KE) peak isometric strength measured with a handheld dynamometer; 40-m walk test; 30-second chair-stand test; and 9-step stair climb test. Reliability was assessed using a 2-way, mixed-effects, single-measures model (3,1), absolute agreement-type intraclass correlation coefficient (ICC). Agreement was assessed using 95% limits of agreement (LOA) and LOA relative to the mean score from test and retest (LOA-%).
Reliability for all tests was very high (ICC ≥ 0.97). LOA (LOA-%) was ±32.3 watt (W) (±22%) for LE power; ±22.7 N·m (±24%) for KE strength; ±0.2 m/s (±10%) for 40-m walk test; ±2.4 repetitions (±14%) for 30-second chair-stand test; and ±2 second (±20%) for stair climb test. A potential participant learning effect was found for all 3 performance-based tests, indicated by the significantly better scores at retest.
The very high reliability found for the performance-based tests supports findings from previous studies and confirms discriminate reliability of these tests on a group level. Also, very high reliability estimates were demonstrated for both muscle function tests. This study also provided estimates of agreement for both performance-based and muscle function tests, which are important to consider when using these tests on an individual level in clinical practice.
When using these tests to monitor changes over time in the clinic, depending on the test, improvements of less than 10% to 24% could be a result of measurement error alone and therefore may not be considered an actual improvement after treatment.
在膝关节骨关节炎（KOA）患者中，应用推荐的基于表现的核心测试和常见肌肉功能测试的重复性仍然存在一些不确定性。本研究的目的是探讨 KOA 患者中推荐的基于表现的核心测试和常见肌肉功能测试的组内可靠性和一致性。
参与者（N=40）存在放射学和/或症状性 KOA，在两次测试之间间隔 3 天，使用以下测试进行评估：诺丁汉力量仪测量的腿部伸肌（LE）最大肌肉力量；手持测力计测量的膝关节伸肌（KE）峰值等长力量；40 米步行测试；30 秒椅站测试；9 步爬楼梯测试。可靠性评估使用 2 路、混合效应、单测量模型（3,1），绝对一致性类型的组内相关系数（ICC）。使用 95%的一致性界限（LOA）和与测试和重测平均值的一致性界限（LOA-%）来评估一致性。
所有测试的可靠性均非常高（ICC≥0.97）。LE 功率的 LOA（LOA-%）为±32.3 瓦（W）（±22%）；KE 强度的 LOA 为±22.7 N·m（±24%）；40 米步行测试的 LOA 为±0.2 m/s（±10%）；30 秒椅站测试的 LOA 为±2.4 次（±14%）；爬楼梯测试的 LOA 为±2 秒（±20%）。所有 3 项基于表现的测试都发现了潜在的参与者学习效应，表现为重测时的得分明显更好。
基于表现的测试的高度可靠性支持了之前研究的发现，并确认了这些测试在组水平上的区分可靠性。此外，还对两种肌肉功能测试的高度可靠性进行了评估。本研究还为基于表现和肌肉功能测试提供了一致性的估计，这在临床实践中在个体水平上使用这些测试时是很重要的。
在临床实践中，使用这些测试来随时间监测变化时，取决于测试，改善小于 10%至 24%可能仅仅是由于测量误差，因此在治疗后可能不被认为是实际的改善。
