Author + information
- Guoxin Fan, MD,
- Shisheng He, MD∗ ( and )
- Zhengqi Chen, MD
- ↵∗Orthopedic Department, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, 301 Yanchang Road, Shanghai 200072, China
We took great interest in the paper by Orme et al. (1) recently published in the Journal; however, we have some concerns regarding the statistical analysis.
As the authors noted, it has already been indicated that the incidence of musculoskeletal pain is associated with higher case volumes and more years in practice for interventional cardiologists. In other words, the total time exposed to a radiation-bearing lead apron might lead to increased risk of musculoskeletal pain. Therefore, it is essential to investigate the association between the total radiation exposure time (self-reported exposure time per week × years in the current profession) and the proportion of work-related pain. Similarly, the association between the total time of wearing a lead apron (time per week × years in the current profession) and the proportion of work-related pain also should be analyzed. Unfortunately, years in current profession was not integrated into the analysis when the authors investigated the factors associated with increase of work-related pain. As a result, this led to some cumbersome and feeble explanations, such as constant and different physical stress to argue why nonphysician employees in the interventional lab reported a higher prevalence of work-related musculoskeletal pain, even if they were younger with fewer working years. If the authors investigated the association between musculoskeletal pain and the total time the catheterization lab operators and staff wore a radiation-bearing lead apron, they might have been to obtain evidence to clarify the issue. Moreover, it might have been more interesting to investigate whether there is any correlation between the pain score and the total time of wearing a lead apron in participants exposed to radiation without taking a pain medication.
In this cross-sectional case-control study, the authors identified no difference in cancer prevalence between groups (9% vs. 9%; p = 0.96). We suspect a significant bias within this analysis because many staff involved in procedures with radiation exposure had fewer working years and less cancer risk, exhibiting a linear/linear-quadratic, no-threshold radiation relationship with stochastic effects (2). Thus, the comparison of cancer prevalence between groups should be stratified by the working years.
Please note: The authors have reported that they have no relationships relevant to the contents of this paper to disclose. Jonathan Tobis, MD, served as Guest Editor for this paper.
- American College of Cardiology Foundation