Department of Neuromedicine and Movement Science, Center for Elite Sports Research, Norwegian University of Science and Technology, Trondheim, Norway.
School of Sport Sciences, UiT the Arctic University of Norway, Tromsø, Norway.
Int J Sports Physiol Perform. 2024 Jul 23;19(9):953-957. doi: 10.1123/ijspp.2024-0057. Print 2024 Sep 1.
Recent methodological recommendations suggest the use of the "3-step method," consisting of calendar-based counting, urinary ovulation testing, and serum blood sampling, for the identification of subtle menstrual disturbances (SMDs). However, the use of the 3-step method is not always feasible, so a less demanding combination of calendar-based counting and urinary ovulation testing, that is, the 2-step method, may be a viable alternative.
To investigate the agreement between the 2- and 3-step methods for the detection of SMDs.
Menstrual cycles (MCs, 98) of 59 athletes were assessed using the 2- and 3-step methods. Regular-length MCs (ie, ≥21 and ≤35 d) were classified as either having no SMD (luteal phase length ≥10 d, midluteal progesterone concentration ≥16 nmol·L-1, and being ovulatory) or having an SMD (eg, short luteal phase [<10 d], inadequate luteal phase [midluteal progesterone concentration <16 nmol·L-1], or being anovulatory). Method agreement was assessed using the McNemar test and Cohen kappa (κ).
Substantial agreement was observed between methods (κ = .72; 95% CI, .53-.91), but the 2-step method did not detect all MCs with an SMD, resulting in evidence of systematic bias (χ2 = 5.14; P = .023). The 2-step method detected 61.1% of MCs that had an SMD ([51.4, 70.8]), as verified using the 3-step method, and correctly identified 100% of MCs without an SMD.
MCs classified as being disturbed using the 2-step method could be considered valid evidence of SMDs. However, MCs classified without SMDs do not definitively confirm their absence, due to the proven underdetection via the 2-step method.
最近的方法学建议建议使用“三步法”，包括基于日历的计数、尿排卵测试和血清血液采样，以识别微妙的月经紊乱（SMD）。然而，三步法的使用并不总是可行的，因此基于日历的计数和尿排卵测试的要求较低的组合，即两步法，可能是一种可行的替代方法。
研究两步法和三步法检测 SMD 的一致性。
使用两步法和三步法评估 59 名运动员的月经周期（MC）98 次。正常长度的 MC（即≥21 且≤35 d）分为无 SMD（黄体期长度≥10 d、中黄体期孕激素浓度≥16 nmol·L-1 且排卵）或有 SMD（如黄体期缩短[<10 d]、黄体期不足[中黄体期孕激素浓度<16 nmol·L-1]或无排卵）。使用 McNemar 检验和 Cohen kappa（κ）评估方法一致性。
两种方法之间存在高度一致性（κ=0.72；95%CI，0.53-0.91），但两步法并未检测到所有有 SMD 的 MC，这表明存在系统偏差（χ2=5.14；P=0.023）。两步法检测到 61.1%的 SMD 月经周期（[51.4，70.8]），与三步法验证一致，并正确识别出 100%无 SMD 的月经周期。
使用两步法分类为紊乱的 MC 可被视为 SMD 的有效证据。然而，由于两步法的检测不足，被分类为无 SMD 的 MC 并不能确定其不存在。
