Abstract
This study determined the impact and influence of published articles on the field of occupational stress. A transdisciplinary approach was used to identify the 50 work-related stress articles with the most lifetime citations and the 50 work-related stress articles with the highest annual citation rates. Studies were categorized based on their primary focus: (a) etiology, (b) predictor of outcome for which occupational stress is the outcome or predictor of outcome for which occupational stress is an independent variable, (c) management/intervention, (d) theory/model/framework, or (e) methodologies. The majority of studies with the highest number of lifetime citations as well as the highest annual citation rates used stress as a predictor or outcome of another factor. The proportion of studies that were categorized by etiology, intervention/management, theory/model/framework, or methodologies was relatively low for both lifetime and annual citations.
Occupational stress is a significant concern for both employees and employers (Richardson & Rothstein, 2008). In the United States, occupational stress is a significant precipitator of up to 80% of all work-related injuries and 40% of workplace turnovers (Atkinson, 2004). In Canada, 3.7 million working adults have reported high levels of stress during their regular workday (Crompton, 2011). Work-related stress has also been identified as a significant contributing factor to organizational inefficiency (Arnetz, 2006), high staff turnover (Avey, Luthans, & Jensen, 2009), absenteeism (Darr & Johns, 2008), and decreased job satisfaction (AbuAlRub, 2004; Flanagan & Flanagan, 2002). Although many epidemiological, clinical, and knowledge translation articles have been published on occupational or work stress, the relative contribution and impact of individual studies on the field is unknown. One way to measure the relative impact of individual occupational stress articles on the discipline is through a citation analysis (Patsopoulos, Analatos, & Ioannidis, 2005; Ponce & Lozano, 2010).
Citation analyses evaluate the influence of individual scientific articles through a methodical examination of raw citation data (Moed, 2006). Within a discipline, highly cited articles are among the most impactful, given that they are referenced most extensively and by extension contribute most to other studies (Sharma & Lawrence, 2014). Moreover, the number of total citations an article accumulates is a reflection of the influence of that article (Garfield, 1986; Lipsman, Woodside, & Lozano, 2014; Sharma & Lawrence, 2014); an evaluation of citation rates identifies papers that are relevant and pertinent (Sharma & Lawrence, 2014). Citation analyses synthesize the literature in a way that supports an understanding of which studies and subfields are most influential within the scientific literature. This approach can also reveal which areas of study within occupational stress research are relatively less developed and need further attention.
Despite the importance of such reviews, to the authors’ knowledge, no citation analysis of occupational stress literature has been published. Therefore, the current study examined the 50 occupational stress articles with the most lifetime citations and the 50 occupational stress articles with the highest annual citation rates. Jointly, the publications examined are some of the most influential and relevant articles in the field of occupational stress.
Method
To retrieve and analyze academic citations, the authors used Publish or Perish (version 4.15.0; Harzing, 2007) software developed by Tarma Software Research and provided free of charge for personal non-profit use (Harzing & Van der Wal, 2007). Using this software, the user can complete a literature search and record multiple citation metrics (e.g., total number of citations, average citations per author, citations per year) on up to 1,000 articles retrieved during a given search. More specifically, Harzing’s Publish or Perish first accesses the scientific literature through Google Scholar to collect raw citation data and then computes and presents numerous citation metrics for each retrieved article.
This search included four keywords specific to work-related stress: “occupational stress,” “job stress,” “workplace stress,” and “work stress.” Articles were retrieved if they included any of the keywords in the study title. The study focused on two citation-based metrics: number of lifetime citations and annual citation rate. The full list of articles generated by Harzing’s Publish or Perish was sorted by the total number of citations, and all articles were reviewed in consecutive order until 50 work-related stress articles with the highest number of lifetime citations met the study inclusion and exclusion criteria (as outlined below). Similarly, the citation rates per year for the 50 most-cited articles on work-related stress were also identified. The two citation lists were not mutually exclusive; an article that had the most lifetime citations could also be among the articles with the highest annual citation rate.
The direction of research in this field was determined by analyzing the topics that were examined in the top 50 articles for each citation metric. After the top 50 articles with the highest total number of citations and the top 50 articles with the highest annual citation rates were identified, they were categorized according to topic of study. The category topics included: (a) etiology, (b) predictor of outcome for which occupational stress is the outcome or predictor of outcome for which occupational stress is an independent variable, (c) management/intervention, (d) theory/model/framework, or (e) methodologies. Studies were examined by topic to determine the relative influence of each topic on research in the field. Higher citation rates suggested that a study was highly influential in the field, and examining the topics of these studies pointed to the direction of research. Moreover, the authors identified the number of articles that may have emanated from a single research project.
Although numerous studies on occupational stress are framed by a theory, model, or framework, the topic of an article fell under this category only if the study directly examined a theory, model, or framework in the research question. Conversely, studies that were rooted in a theory, model, or framework were not included in this category. For example, a study that examined the relationship between workers’ years of experience and occupational stress in the context of a particular job stress model would not fall under this category. However, a study that examined whether or not a job stress model accounted for all factors that contribute to occupational stress would fall under this category. Therefore, the topic of an article was categorized as theory/model/framework if a theory, model, or framework was directly addressed in the research question.
Quality Assurance
To increase the methodological rigor of the findings, two independent raters conducted the citation analysis and interrater agreement on the top 50 articles was identified for each citation metric. Interrater reliability was calculated using Cohen’s kappa for interrater correlation (Haley & Osberg, 1989). After articles were identified, they were entered into an electronic database and coded by topic by the first rater (B.N.). A second rater was provided a random sample of 25% of the first rater’s data. The first rater coded articles independently of the second rater (J.C.). The process was replicated by the second rater. Inter-observer agreement was achieved for both citation cohorts (n = 100). Cohen’s kappa was calculated to be between 0.91 and 0.95, indicating a close agreement between the two observers for both citation groups.
Articles were included if they were primary publications that principally investigated work-related stress, as determined by an abstract screen. This review included both quantitative and qualitative research, including program evaluations, as well as theoretical articles. Books, letters, conference proceeding abstracts, unpublished manuscripts, and theses were excluded. To be included, articles were published in English in peer-reviewed journals and of relevance to the topic (Figure 1). All members of the research team reviewed the inclusion and exclusion of articles. No restrictions were placed on year of publication. The citation metrics are accurate to October 13, 2015.
Flow diagram representing the study selection process for the (A) lifetime cohort and (B) annual citation rate cohort.
Results
The results of the 50 occupational stress articles with the most lifetime citations and the 50 occupational stress articles with the highest annual citation rates are presented in Tables 1 and 2. The mean number of lifetime citations for the top 50 most-cited articles was 481.86 (SD ±154.22). Values ranged from 325 to 910 citations. The mean number of annual citations for the top 50 articles was 34.03 (SD ±12.69) with values ranging from 22.58 citations per year to 76.4 citations per year. Of the top 50 articles with the highest annual citation rate, 32 (64%) were also listed as a top 50 article with the most lifetime citations (Figure 2). In terms of methodological approach, cross-sectional studies were the most frequently used design for both categories (Table 3).
Fifty Articles on Occupational Stress With Most Lifetime Citations
Multiple articles emanated from single research project.
Fifty Articles on Occupational Stress With the Highest Annual Citation Rate
Multiple articles emanated from single research project.
Organization of publications comprising both cohorts by year.
Study Design
Etiology
Etiology was one of the study topics assessed in this analysis. Six percent of the top 50 articles with the most lifetime citations (three of 50 studies) addressed the etiology of occupational stress. Among the list of articles with the highest annual citation rate, 4% (two of 50 studies) were categorized under etiology.
Predictor of Outcome (Occupational Stress as Outcome)
Studies that appeared on both lists focused on the effect of occupational risk factors on occupational stress. Thirty-eight percent (19 studies) of the top 50 articles with the highest number of lifetime citations (Table 1) were in this category. Forty percent (20 studies) of the top 50 studies with the highest annual citation rate (Table 2) focused on this topic.
This category included the second highest proportion of articles on both lists. Studies that focused on the effects of other factors on the development of occupational stress have a relatively high impact on the field; however, these articles had less impact than studies that examined stress as a predictor of another variable. Overall, the results indicated significant research in this field has focused on occupational stress as an outcome variable.
Predictor of Outcome (Occupational Stress as an Independent Variable)
Studies among both lists were also conducted on the relationship between stress and an outcome variable. Fifty percent (25 studies) of the top 50 articles with the highest number of lifetime citations focused on occupational stress as a predictor of another outcome. Forty-six percent (23 studies) of the top 50 articles with the highest annual citation rate addressed this topic. The largest proportion of articles from both the lifetime and annual citation lists were in this category.
The results suggest that occupational stress research is most affected by studies that have examined the relationship between occupational stress as an independent variable and another outcome variable. In other words, the consequences of occupational stress have been studied more than other areas of occupational stress investigation. In particular, occupational stress as a predictor of heart disease is a trending topic in the literature as evidenced by the articles with the most lifetime citations (Table 1). Similarly, the articles with the fourth and fifth highest annual citations both examined heart disease as an outcome of occupational stress (Table 2). These two findings suggest that studies about occupational stress as a predictor of heart disease are the most influential in the field and have the highest impact on future research.
In addition, the most-cited studies on occupational stress have focused on particular occupations (i.e., teaching and nursing).
Management/Intervention
The topic of managing or intervening to reduce or eliminate occupational stress and/or its effects is also among the top 50 articles with the most lifetime citations and highest annual citation rate. Among studies with the most lifetime citations, 1% of articles examined an intervention or management program. Four percent (two of 50) of articles with the highest annual citation rate were also in this category.
Intervention and/or management programs for occupational stress have not been the focus of published studies. In contrast to studies of occupational stress as independent or dependent variables, few studies have examined interventions to mitigate stress. It is one of the top cited topics, but does not comprise the majority of top cited articles. The prevalence of predictor of outcome studies and rarity of intervention studies may reflect the limited understanding of causes of occupational stress, a precursor to determining how to reduce work-related stress.
It is interesting to note that studies on the role of negative affectivity as a mediator between occupational stress and other variables have also been among the top cited in current literature. The high number of citations reflects a trend in examining methodologies, in particular examining the role of negative affectivity in measuring occupational stress.
Theory/Model/Framework and Methodologies
Of the top 50 articles with the highest lifetime citations, 8% (four of 50) addressed a theory/model/framework or methodology. Among the top 50 articles with the highest annual citation rate, 4% (two of 50) addressed a theory/model/framework. The data suggested that examining theory/model/framework is not a trend in this field of research and has little impact on future research studies.
Discussion
The purpose of this study was to use citation analysis to identify specific articles and topics cited most frequently in the occupational stress literature. The results showed that predictor of outcome was the most prevalent topic among the top cited studies, particularly occupational stress as a predictor of coronary heart disease; the most frequently studied group in the identified studies were nurses (15 studies). This finding suggests that occupational stress in health care environments is a serious occupational health hazard and deserves additional investigation as an outcome of providing nursing care. Studies on etiology, intervention and/or management, methodologies, and theory/model/framework were cited far less in the literature compared with the predictor and outcome studies.
The majority of studies in this review were cross-sectional and descriptive. Additional research on the efficacy of interventions to reduce or eliminate occupational stress using methodologically rigorous designs (e.g., randomized control trials) is needed. Moreover, studies are needed to better understand the long-term effects of occupational stress management interventions designed for various occupational groups (Richardson & Rothstein, 2008). These approaches are supported by recent literature in nursing (Adriaenssens, De Gucht, & Maes, 2015; Heeb & Haberey-Knuessi, 2014) and education (Antoniou, Ploumpi, & Ntalla, 2013; Tytherleigh, Webb, Cooper, & Ricketts, 2005). Although descriptive studies can inform researchers’ understanding of occupational stress in particular occupations (e.g., nursing), these research studies can also clarify the causes of occupational stress.
Limitations
Harzing’s Publish or Perish can only analyze a limited number of articles (i.e., 1,000) per query. Because the pool of articles analyzed was limited to 1,000, the analysis may not reflect the top cited articles within the entire pool of articles in this field, but only the top cited articles within the 1,000 that were queried. In addition, the program only queries articles accessible from the Google Scholar database. Therefore, the entire body of literature for this field may not have been included in the analysis, which may have biased the articles found to be top cited in the literature.
Conclusion
Studies that have been conducted on the relationship between occupational stress and related variables have the highest impact on research in the field of occupational stress. The field is most influenced by articles that pertain to the effects of stress on another outcome variable, particularly coronary heart disease. Articles that examine occupational stress as an outcome of other factors also appear to have a relatively high impact on the field. Top cited studies that focus on a specific occupation include teaching, nursing, and the health industry in general. In contrast, few of the top cited studies examined occupational stress etiology, intervention and/or management programs, theories/models/frameworks, or methodologies. Because the top cited studies examined predictors and outcomes of occupational stress, the authors suggest that factors associated with occupational stress are still being identified. Although most published studies examined relationships between stress and other variables, this study demonstrated that other occupational stress research studies are limited. Understanding which areas of occupational stress research are most influential, and therefore those areas that receive researcher attention and grant support, could direct future research in this field.
Applying Research to Practice
This citation analysis study provides an overview of the current state of research in the area of occupational stress with a focus on nursing. Categorizing studies by their primary focus and their citation rates (annual and lifetime), industry, and design provides meaningful metrics in conducting research. Moreover, this approach provides an understanding of the existing literature and identifies research opportunities for future investigation.
Footnotes
Authors’ Contributions
All authors substantially contributed to the conception of the work and to the interpretation of the data. Furthermore, all authors substantially contributed to the drafting and revising of the work. All authors are in agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy and integrity of any part of the work are appropriately investigated and resolved. All authors approve of the final version to be published.
Conflict of Interest
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) received no financial support for the research, authorship, and/or publication of this article.
Author Biographies
Behdin Nowrouzi is an occupational therapist and postdoctoral fellow in the Centre for Research in Occupational Safety and Health, Laurentian University.
Christine Nguyen is a research assistant studying at McMaster University, Hamilton, Ontario, Canada.
Jennifer Casole is a Special Education Department Head at Loretto College, Toronto, Ontario, Canada.
Behnam Nowrouzi-Kia is a medical student at the Michael DeGroote School of Medicine, Hamilton, Ontario, Canada.