Secondary Logo

Journal Logo

Response to Predictors of Disability Retirement With Special Reference to Workplace Bullying

Nielsen, Morten, Birkeland, PhD; Emberland, Jan, Shahid, MSC; Knardahl, Stein, PhD

Journal of Occupational and Environmental Medicine: May 2018 - Volume 60 - Issue 5 - p e282
doi: 10.1097/JOM.0000000000001317

National Institute of Occupational Health, Oslo, Norway.

Address correspondence to: Morten Birkeland Nielsen, PhD, National Institute of Occupational Health, PB 8149 Dep, N-0033 Oslo, Norway (

The authors have no conflicts of interest.

Readers are invited to submit letters for publication in this department. Submit letters online at Choose “Submit New Manuscript.” A signed copyright assignment and financial disclosure form must be submitted with the letter. Form available at under Author and Reviewer information.

To the Editor:

We thank Dr. Tomoyuki Kawada for his interesting response to our article “Workplace Bullying as a Predictor of Disability Retirement: A Prospective Registry Study of Norwegian Employees.” In his letter, Dr. Kawada expresses concerns about the potential omission of a series of additional variables that may have confounded our findings. While we agree that all of the proposed variables are important to examine in relation to workplace bullying, we must note that the main aim of our study was to establish the relatively novel bivariate association between exposure to bullying and registry-based disability retirement. As very few previous studies have examined this relation, it is important to establish this initial relationship before moving on to more advanced study designs that include additional factors. Such an approach to testing associations is in line with Spector and Brannick1 who propose that researchers should first establish a single relationship of a new construct with another variable (or small number of variables) before systematically attempting to explain the reasons for that relationship through a series of alternative studies that contain confounding variables. Consequently, by showing that workplace bullying has a basic relation with disability retirement, our study represents a starting point for future research on workplace bullying and disability retirement. To add to the understanding of the underlying mechanisms and conditions that can explain when and how bullying is associated with disability retirement, upcoming studies may extend our study by testing the factors suggested by Dr. Kawada.

Back to Top | Article Outline


1. Spector PE, Brannick MT. Methodological urban legends: the misuse of statistical control variables. Organ Res Methods 2011; 14:287–305.
Copyright © 2018 by the American College of Occupational and Environmental Medicine