TY - JOUR AU - McCambridge, Jim AU - Kalaitzaki, Eleftheria AU - White, Ian R AU - Khadjesari, Zarnie AU - Murray, Elizabeth AU - Linke, Stuart AU - Thompson, Simon G AU - Godfrey, Christine AU - Wallace, Paul PY - 2011 DA - 2011/11/18 TI -问卷长度或相关性对在线试验减员的影响:随机对照试验JO - J Med Internet Res SP - e96 VL - 13 IS - 4kw -减员KW -保留KW -缺失数据KW -响应率KW -酒精KW -在线AB -背景:在线研究中影响响应率和减员的因素研究有限。在线实验嵌套在试验阶段(研究1,n = 3780)和主试验阶段(研究2,n = 2667)中，对危险饮酒者进行基于网络干预的评估:“喝下你的饮料”随机对照试验(DYD-RCT)。目的:目的是确定问卷长度和相关性的差异是否会影响在线试验中的随访损失。方法:采用随机对照试验设计。所有同意进入DYD-RCT并完成主要结果问卷的参与者在基线和随访时被随机分配完成四份次要结果问卷中的一份。这些问卷在长度上有所不同(额外的23或34项与10项)和相关性(酒精问题与精神健康)。结果测量是在两个随访间隔中完成随访的参与者的比例:1个月和3个月后的研究1和3个月后的研究2。结果:在所有四个随访间隔中，额外的问卷长度对随访没有显著影响。随机化到相关性较低的问卷调查导致四项评估中的两项随访率显著降低(在1个月后的研究1和12个月后的研究2中，绝对差异为4%，95%置信区间[CI]为0%-8%)。 A post hoc pooled analysis across all four follow-up intervals found this effect of marginal statistical significance (unadjusted difference, 3%, range 1%-5%, P = .01; difference adjusted for prespecified covariates, 3%, range 0%-5%, P = .05). Conclusions: Apparently minor differences in study design decisions may have a measurable impact on attrition in trials. Further investigation is warranted of the impact of the relevance of outcome measures on follow-up rates and, more broadly, of the consequences of what we ask participants to do when we invite them to take part in research studies. Trial registration: ISRCTN Register 31070347; http://www.controlled-trials.com/ISRCTN31070347/31070347 Archived by WebCite at (http://www.webcitation.org/62cpeyYaY) SN - 1438-8871 UR - //www.mybigtv.com/2011/4/e96/ UR - https://doi.org/10.2196/jmir.1733 UR - http://www.ncbi.nlm.nih.gov/pubmed/22100793 DO - 10.2196/jmir.1733 ID - info:doi/10.2196/jmir.1733 ER -