Measurement errors usually arise during the longitudinal data collection process. Ignoring the effects of measurement errors will lead to invalid estimates. The Lifestyle Education for Activity and Nutrition (LEAN) study was designed to assess the effectiveness of intervention for enhancing weight loss over nine months. The covariates systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured at baseline, month 4, and month 9. At each assessment time, there were two replicate measurements for SBP and DBP. The replicate measurement errors of SBP follow different distributions, as does DBP. To account for the distributional difference of replicate measurement errors, a new method for analyzing longitudinal data with replicate covariate measurement errors is developed based on the empirical likelihood method. The asymptotic properties of the proposed estimator are established under some regularity conditions. The confidence region for the parameters of interest can be constructed based on the chi-squared approximation without estimating the covariance matrix. Additionally, the proposed empirical likelihood estimator is asymptotically more efficient than the estimator of Lin et al. (2018). Extensive simulations demonstrate that the proposed method can eliminate the effects of measurement errors in the covariate and has a high estimation efficiency. The proposed method indicates the significant effect of the intervention on BMI in the LEAN study.
翻译:在纵向数据收集过程中通常会出现测量错误。无视测量错误的影响,将会导致无效的估计数。活动与营养(LEAN)的生活方式教育(LEAN)研究旨在评估干预措施在9个月中提高体重损失的效果。共变相系统血压(SBP)和透析血压(DBP)在基准、第4个月和9个月中测量。在每次评估期间,都对SBP和DBP有两种相同的测量标准。SBP的复制性测量错误与DBP一样遵循不同的分布。为了说明复制测量误差的分布差异,根据经验可能性方法开发了一种用复制变量测量误差分析长动数据的新方法。提议的血压(SBPP)和透析血压(DBPP)的随机性特性在某些定期条件下得到确定。对利益参数的信任区域可以建筑在对相近的相近度下,而不估算相异性矩阵。此外,拟议的经验概率估测算法比Lin 和AL的估测误差率分析法(2018年) 拟议的测测法对Lival法的显著效果的模拟表明,拟议的测算法在Livali 效率的测算法的测算法可以消除高效。(BIMI方法的测算法的测算法。(2018)。拟议的测测算法的测算法的测测测算法的测算法的测算法可以说明高效果。