Review confirms prevention system’s message about injury risks and new workers

IWH systematic review finds evidence for higher risks of acute injuries, but inconclusive evidence for MSD risks, during workers’ first year

Published: July 30, 2019

In the past 10 years, practitioners and policy-makers in occupational health and safety (OHS) have widely embraced and shared the message that new workers, regardless of their age, are at greater risk of work injury.

This is due in part to a growing body of research on OHS and job tenure—including research conducted in 2006 and 2013 by the Institute for Work & Health (IWH). The IWH research showed that workers who had been in a job a month or less had three times the risk of a lost-time injury as those who had been in a job for over a year (see What Research Can Do column on page 2).

Yet, until recently, a systematic review of the research on job tenure and risk of work injury had never been done. Now, one of the people behind the IWH studies has published a systematic review on that very issue.

The review, led by IWH Scientist Dr. Curtis Breslin, found different levels of evidence for different types of injuries with respect to the association between job tenure and risk of work injury. Specifically, the review found:

  • confirmation that risks of acute injury are indeed higher during workers’ first year at a job or a firm; and
  • inconclusive evidence about the risks of musculoskeletal symptoms, injuries or disorders during workers’ first year at a job or a firm.

One of the things this systematic review made clear is that researchers and OHS stakeholders need to be specific about how they define ‘new worker’ and what types of injuries they are referring to when looking at the relationship between newness and work injury, says Breslin. The review was published online in May 2019 in Occupational and Environmental Medicine (doi:10.1136/oemed-2018-105639).

Multiple definitions of ‘newness’

To conduct the systematic review, Breslin’s team searched the peer-reviewed literature for articles published between 1995 and January 2018 on job tenure and risk of work injury.

The team found 128 relevant studies that met review criteria: they were quantitative studies about people doing paid work; they examined the length of time working at a particular job, firm or industry; and they had a method for taking into account other factors that may have affected risk of work injury. After studies were assessed for quality, the team was left with 51 medium- and high-quality studies.

These 51 studies defined newness very differently, with varying lengths of time at a job, at a firm or in an industry. Breslin’s team decided to concentrate on the findings from 12 medium- or high-quality studies that considered a new worker to be someone who had been at a job or firm for 12 months or less. “We went with what people commonly understand to be newness,” says Breslin.

Out of six medium- and high-quality studies examining acute work injury among workers whose job or firm tenure was less than a year, four studies showed a significantly higher risk for new workers. Two studies found no support for a higher risk.

Out of six medium- and high-quality studies examining musculoskeletal symptoms, injuries or disorders, the evidence was inconclusive.

‘Three times higher’ statistic still stands

What does the new review mean for the frequently heard message that workers are three times more likely to be hurt in their first month in a job than they are after their first year? Breslin says safety advocates and practitioners, particularly those in Ontario’s prevention system, can still confidently cite that statistic.

The 2006 and 2013 studies underpinning that message were strong because they accounted for age and they drew on workers’ compensation lost-time data to quantify workers’ increased risk specific to their first month, says Breslin. No study in the review attempted to replicate that finding, nor did any refute it, he adds.

Despite the evidence for, and widespread recognition of, the higher risks linked with newness, Breslin notes that we need further research to better understand the underlying reasons for this link.

Is it because new workers lack familiarity with the setting, because they lack the skills to do the job or to wear personal protection properly, or because they don’t feel empowered to speak up or ask questions? asks Breslin.

Or is it because they’re the ones doing the more hazardous jobs? We actually don’t have a good understanding of the extent to which workers are exposed to hazards when they’re new to the job.