From the Barcelona Institute for Global Health (ISGlobal), Barcelona, Spain.
Universitat Pompeu Fabra (UPF), Barcelona, Spain.
Epidemiology. 2019 Jan;30(1):145-153. doi: 10.1097/EDE.0000000000000932.
MOBI-Kids is a 14-country case-control study designed to investigate the potential effects of electromagnetic field exposure from mobile telecommunications devices on brain tumor risk in children and young adults conducted from 2010 to 2016. This work describes differences in cellular telephone use and personal characteristics among interviewed participants and refusers responding to a brief nonrespondent questionnaire. It also assesses the potential impact of nonparticipation selection bias on study findings.
We compared nonrespondent questionnaires completed by 77 cases and 498 control refusers with responses from 683 interviewed cases and 1501 controls (suspected appendicitis patients) in six countries (France, Germany, Israel, Italy, Japan, and Spain). We derived selection bias factors and estimated inverse probability of selection weights for use in analysis of MOBI-Kids data.
The prevalence of ever-regular use was somewhat higher among interviewed participants than nonrespondent questionnaire respondents 10-14 years of age (68% vs. 62% controls, 63% vs. 48% cases); in those 20-24 years, the prevalence was ≥97%. Interviewed controls and cases in the 15- to 19- and 20- to 24-year-old age groups were more likely to have a time since start of use of 5+ years. Selection bias factors generally indicated a small underestimation in cellular telephone odds ratios (ORs) ranging from 0.96 to 0.97 for ever-regular use and 0.92 to 0.94 for time since start of use (5+ years), but varied in alternative hypothetical scenarios considered.
Although limited by small numbers of nonrespondent questionnaire respondents, findings generally indicated a small underestimation in cellular telephone ORs due to selective nonparticipation.
MOBI-Kids 是一项在 2010 年至 2016 年间进行的 14 个国家的病例对照研究，旨在调查移动电信设备产生的电磁场暴露对儿童和青少年脑瘤风险的潜在影响。本研究描述了参与和拒绝接受简短的非应答者问卷的应答者之间手机使用情况和个人特征的差异，并评估了非参与选择偏差对研究结果的潜在影响。
我们比较了来自六个国家（法国、德国、以色列、意大利、日本和西班牙）的 683 名受访者和 1501 名对照者（疑似阑尾炎患者）的应答者与 77 名病例和 498 名对照者拒绝者完成的非应答者问卷。我们得出了选择偏差因素，并估计了选择权重的倒数概率，以用于分析 MOBI-Kids 数据。
10-14 岁受访者中，接受访谈的参与者比非应答者问卷应答者中曾经经常使用手机的比例略高（对照组为 68%，病例组为 63%）；在 20-24 岁组中，该比例≥97%。15-19 岁和 20-24 岁年龄组的受访者和病例更有可能开始使用手机的时间超过 5 年。选择偏差因素通常表明，对手机使用的比值比（OR）的低估幅度较小，范围在经常使用手机的 OR 从 0.96 到 0.97，开始使用手机的时间（5 年以上）的 OR 从 0.92 到 0.94，但在考虑的替代假设情景中有所不同。
尽管非应答者问卷应答者的数量有限，但研究结果普遍表明，由于选择性不参与，手机 OR 存在轻微低估。
