Occupational Cancer Research Centre, Cancer Care Ontario, Toronto, Ontario, Canada.
School of Occupational and Public Health, Ryerson University, Toronto, Ontario, Canada.
Occup Environ Med. 2020 Oct;77(10):659-665. doi: 10.1136/oemed-2019-106200. Epub 2020 Jul 9.
Declining participation has been observed in previous epidemiological studies, could occupational risk factor epidemiology be particularly vulnerable to this trend? The objective of this study was to assess trends of participation rates in occupational case-control studies.
Five prominent occupational and epidemiological journals were pre-selected and all articles published between 1991 and 2017 were screened for case-control studies of occupational risk factors for chronic disease outcomes. The primary independent variable was median year of data collection, while the primary outcome variable was reported participation rate. We conducted linear regression, adjusting for study characteristics that included study gender mix, location of recruitment, disease outcome, and data collection method.
A total of 180 studies published in the five journals were included in the final analysis. The mean participation was higher for cases (78.9%) than for controls (71.5%). In linear regression, a significant trend of decreasing participation was observed for both cases with a percent change of -0.50 per year (95% CI -0.75 to -0.25) for cases and a percent change of -0.95 per year (95% CI -1.23 to -0.67) for controls. After adjustment for study gender mix, location, disease outcome, and data collection method, the trend remained statistically significant for both case and control groups.
Declining participation rates in case-control studies of occupational risk factors may reflect an overall decline of participation in population-based samples. Lower participation rates introduce the potential for bias and may deter future population-based studies of occupational risk factors.
先前的流行病学研究观察到参与率下降，职业风险因素流行病学是否特别容易受到这一趋势的影响？本研究的目的是评估职业病例对照研究中参与率的趋势。
预先选择了五本著名的职业和流行病学期刊，并对 1991 年至 2017 年期间发表的所有职业慢性病结局风险因素病例对照研究文章进行筛选。主要的独立变量是数据收集的中位数年份，而主要的结果变量是报告的参与率。我们进行了线性回归，调整了研究特征，包括研究的性别混合、招募地点、疾病结局和数据收集方法。
最终分析共纳入了这五个期刊上发表的 180 项研究。病例的平均参与率（78.9%）高于对照（71.5%）。在线性回归中，病例和对照的参与率均呈显著下降趋势，每年的百分比变化分别为-0.50（95%CI -0.75 至-0.25）和-0.95（95%CI -1.23 至-0.67）。调整研究的性别混合、地点、疾病结局和数据收集方法后，病例和对照两组的趋势仍然具有统计学意义。
职业风险因素病例对照研究中参与率的下降可能反映了基于人群样本参与率的整体下降。较低的参与率可能引入偏倚的风险，并可能阻碍未来职业风险因素的基于人群的研究。
