Comparison of pregnancy outcomes following preimplantation genetic testing for aneuploidy using a matched propensity score design.

STUDY QUESTION: Does preimplantation genetic testing for aneuploidy (PGT-A) increase the likelihood of live birth among women undergoing autologous IVF who have fertilized embryos? SUMMARY ANSWER: PGT-A is associated with a greater probability of live birth among women 35 years old and older who are undergoing IVF. WHAT IS KNOWN ALREADY: Previous studies evaluating the association between PGT-A and the incidence of live birth may be prone to confounding by indication, as women whose embryos undergo PGT-A may have a lower probability of live birth due to other factors associated with their increased risk of aneuploidy (e.g. advancing age, history of miscarriage). Propensity score matching can reduce bias where strong confounding by indication is expected. STUDY DESIGN, SIZE, DURATION: We conducted a retrospective cohort study utilizing data from women who underwent autologous IVF treatment, had their first oocyte retrieval at our institution from 1 January 2011 through 31 October 2017 and had fertilized embryos from this retrieval. If a woman elected to use PGT-A, all good quality embryos (defined as an embryo between Stages 3 and 6 with Grade A or B inner or outer cell mass) were tested. We only evaluated cycles associated with the first oocyte retrieval in this analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS: Our analytic cohort included 8227 women. We used multivariable logistic regression to calculate a propensity score for PGT-A based on relevant demographic and clinical factors available to the IVF provider at the time of PGT-A or embryo transfer. We used the propensity score to match women who did and did not utilize PGT-A in a 1:1 ratio. We then used log-binomial regression to compare the cumulative incidence of embryo transfer, clinical pregnancy, miscarriage and live birth between women who did and did not utilize PGT-A. Because the risk of aneuploidy increases with age, we repeated these analyses among women <35, 35-37 and ≥38 years old based on the Society for Assisted Reproductive Technology's standards. MAIN RESULTS AND THE ROLE OF CHANCE: Overall, women with fertilized embryos who used PGT-A were significantly less likely to have an embryo transfer (risk ratios (RR): 0.78; 95% CI: 0.73, 0.82) but were more likely to have a cycle that resulted in a clinical pregnancy (RR: 1.15; 95% CI: 1.04, 1.28) and live birth (RR: 1.21; 95% CI: 1.08, 1.35) than women who did not use PGT-A. Among women aged ≥38 years, those who used PGT-A were 67% (RR: 1.67; 95% CI: 1.31, 2.13) more likely to have a live birth than women who did not use PGT-A. Among women aged 35-37 years, those who used PGT-A were also more likely to have a live birth (RR: 1.27; 95% CI: 1.05, 1.54) than women who did not use PGT-A. In contrast, women <35 years old who used PGT-A were as likely to have a live birth (RR: 0.91; 95% CI: 0.78, 1.06) as women <35 years old who did not use PGT-A. LIMITATIONS, REASONS FOR CAUTION: We were unable to abstract several potential confounding variables from patients' records (e.g. anti-Mullerian hormone levels and prior IVF treatment), which may have resulted in residual confounding. Additionally, by restricting our analyses to cycles associated with the first oocyte retrieval, we were unable to estimate the cumulative incidence of live birth over multiple oocyte retrieval cycles. WIDER IMPLICATIONS OF THE FINDINGS: Women aged 35 years or older are likely to benefit from PGT-A. Larger studies might identify additional subgroups of women who might benefit from PGT-A. STUDY FUNDING/COMPETING INTEREST(S): No funding was received for this study. D.S. reports that he is a member of the Cooper Surgical Advisory Board. The other authors report no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

To test or not to test? A framework for counselling patients on preimplantation genetic testing for aneuploidy (PGT-A).

STUDY QUESTION: What is the treatment path and cumulative live birth (CLB) rate from a single oocyte retrieval of patients who intend to pursue PGT-A at the start of an IVF cycle compared to matched controls? SUMMARY ANSWER: The choice of PGT-A at the start of the first IVF cycle decreases the CLB per oocyte retrieval for patients <38 years of age, however patients ≥38 years of age benefit significantly per embryo transfer (ET) when live birth (LB) is evaluated. WHAT IS KNOWN ALREADY: PGT-A has been shown to reduce the practice of transferring multiple embryos and to confer a higher live birth rate per transfer. STUDY DESIGN, SIZE, DURATION: This is a retrospective cohort study from December 2014 to September 2016, involving 600 patients: those intending PGT-A for their first IVF cycle (N = 300) and their matched controls. Post-hoc power calculations (alpha of 0.05, power of 0.80) indicated that our study was powered adequately to demonstrate significant differences in CLB per retrieval and LB per transfer. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study was performed at a large academically affiliated infertility practice where approximately 80% of patients have insurance coverage for fertility care. Patients were identified through electronic medical records, and those who intended to pursue PGT-A at the start of stimulation were assessed. Patients were matched by age, time of oocyte retrieval and oocyte yield to the same number of controls. CLB outcomes per single retrieval, including the fresh and frozen transfers arising from the initial stimulation cycle, were calculated. MAIN RESULTS AND THE ROLE OF CHANCE: PGT-A was not beneficial when CLB rate was assessed per retrieval, however its benefits were significant when LB rate was assessed per transfer. First cycle, <38 year-old patients who intended to have PGT-A had a significantly (P < 0.001) lower CLB rate per oocyte retrieval compared to controls (49.4% vs. 69.1%). Conversely, patients ≥ 38 years in the PGT-A group had similar CLB rates compared to controls per oocyte retrieval, while LB rates per transfer were doubled compared to controls (62.1% vs. 31.7%; P < 0.001). Of the first-cycle PGT-A and control patients, 25.3% and 2.3% failed to achieve a transfer, respectively. LIMITATIONS, REASONS FOR CAUTION: This is not a true intention-to-treat study, due to its retrospective nature. Additionally, the number of patients with two or more previous miscarriages was significantly greater in the PGT-A group as compared to controls, however a sub-analysis showed that this failed to impact outcomes. WIDER IMPLICATIONS OF THE FINDINGS: The findings indicate that PGT-A may be detrimental for those <38 years old undergoing their first IVF cycle. PGT-A has the greatest clinical impact when a transfer is achieved in the ≥38 years old population. This study evaluates the typical treatment path following a patient's choice to pursue PGT-A at the cycle start, and can be used as a guide for counselling patients in relation to age and cycle number. STUDY FUNDING/COMPETING INTEREST(S): None. TRIAL REGISTRATION NUMBER: N/A.

Development and validation of a fatigue assessment scale for U.S. construction workers.

OBJECTIVE: To develop a fatigue assessment scale and test its reliability and validity for commercial construction workers. METHODS: Using a two-phased approach, we first identified items (first phase) for the development of a Fatigue Assessment Scale for Construction Workers (FASCW) through review of existing scales in the scientific literature, key informant interviews (n = 11) and focus groups (three groups with six workers each) with construction workers. The second phase included assessment for the reliability, validity, and sensitivity of the new scale using a repeated-measures study design with a convenience sample of construction workers (n = 144). RESULTS: Phase one resulted in a 16-item preliminary scale that after factor analysis yielded a final 10-item scale with two sub-scales ("Lethargy" and "Bodily Ailment"). During phase two, the FASCW and its subscales demonstrated satisfactory internal consistency (alpha coefficients were FASCW [0.91], Lethargy [0.86] and Bodily Ailment [0.84]) and acceptable test-retest reliability (Pearson Correlations Coefficients: 0.59-0.68; Intraclass Correlation Coefficients: 0.74-0.80). Correlation analysis substantiated concurrent and convergent validity. A discriminant analysis demonstrated that the FASCW differentiated between groups with arthritis status and different work hours. CONCLUSIONS: The 10-item FASCW with good reliability and validity is an effective tool for assessing the severity of fatigue among construction workers.

Correlation between safety climate and contractor safety assessment programs in construction.

BACKGROUND: Contractor safety assessment programs (CSAPs) measure safety performance by integrating multiple data sources together; however, the relationship between these measures of safety performance and safety climate within the construction industry is unknown. METHODS: Four hundred and one construction workers employed by 68 companies on 26 sites and 11 safety managers employed by 11 companies completed brief surveys containing a nine-item safety climate scale developed for the construction industry. CSAP scores from ConstructSecure, Inc., an online CSAP database, classified these 68 companies as high or low scorers, with the median score of the sample population as the threshold. Spearman rank correlations evaluated the association between the CSAP score and the safety climate score at the individual level, as well as with various grouping methodologies. In addition, Spearman correlations evaluated the comparison between manager-assessed safety climate and worker-assessed safety climate. RESULTS: There were no statistically significant differences between safety climate scores reported by workers in the high and low CSAP groups. There were, at best, weak correlations between workers' safety climate scores and the company CSAP scores, with marginal statistical significance with two groupings of the data. There were also no significant differences between the manager-assessed safety climate and the worker-assessed safety climate scores. CONCLUSIONS: A CSAP safety performance score does not appear to capture safety climate, as measured in this study. The nature of safety climate in construction is complex, which may be reflective of the challenges in measuring safety climate within this industry. Am. J. Ind. Med. 56:1463-1472, 2013. © 2013 Wiley Periodicals, Inc.

Characterizing the Health and Safety Concerns of U.S. Rideshare Drivers: A Qualitative Pilot Study.

BACKGROUND: Despite the growth and popularity of gig work, limited information exists about the occupational health and safety concerns faced by individuals who are employed through ridesharing online applications. In this qualitative study, we characterized the perceived health and safety concerns of drivers employed by rideshare companies. METHODS: During September-October 2019, we requested car rides, using digital rideshare platforms. During the ride, drivers responded verbally to a brief closed-end sociodemographic and work characteristics survey. A semi-structured interview script was used to collect rideshare driver perceptions on health and safety risks. FINDINGS: A total of 35 rideshare drivers of group mean age of 43.1 ± 11.2 years were interviewed, of whom 77.1% were male and 82.9% identified as Latino. Sixty percent of participants reported rideshare as their primary job, working an average of 47.9 ± 19.6 hours weekly (minimum = 6 hours, maximum = 84 hours). Drivers enjoyed job autonomy yet faced stressors such as passenger risky behavior, car accidents, and lack of policies that protect the driver. Rideshare drivers also raised concerns about their current health status, economic pressures, and worker safety. CONCLUSION/APPLICATION TO PRACTICE: Drivers are forced to extend work hours to support themselves financially, exacerbating their current health concerns and safety risks as it means more time spent working in their sedentary job, compromising their mental and physical health as well as their safety. Occupational health and safety programs geared toward workers in the gig economy are needed.

Firefighter Well-Being Defined and Operationalized at the Organizational and Worker Level: A Qualitative Study.

OBJECTIVE: The aim of the study is to define and explore organizational- and worker-level factors of firefighter well-being. METHODS: Qualitative data were collected using interviews and focus group sessions among 17 career firefighters across 4 fire departments. Interviews were recorded and transcribed, and a general inductive approach was used to code similar concepts into themes. RESULTS: Firefighters defined well-being as being content with oneself and being able to balance ones' emotional, mental, and physical health. Themes contributing to firefighter well-being include the nature of the job, the influence of others, and physical health. Subthemes mapping to themes include dealing with trauma, compartmentalizing work and home life, coworkers and station culture, the role of superiors on attitudes and practices, being a reliable firefighter, and lack of sleep. CONCLUSIONS: Career firefighters describe well-being as a holistic approach to balancing emotional, mental, and physical health.

Assessment of organizational readiness for participatory occupational safety, health and well-being programs.

BACKGROUND: Organizational readiness for change measures were reviewed to develop an assessment tool for guiding implementation of an occupational safety and health program based on Total Worker Health (TWH) principles. Considerable conceptual ambiguity in the theoretical and empirical peer-reviewed literature was revealed. OBJECTIVE: Develop and validate an assessment tool that organizations can use to prepare for implementation of a participatory TWH program. METHODS: Inclusion criteria identified 29 relevant publications. Analysis revealed eight key organizational characteristics and predictors of successful organizational change. A conceptual framework was created that subject matter experts used to generate prospective survey items. Items were revised after pretesting with 10 cognitive interviews with upper-level management and pilot-tested in five healthcare organizations. Reliability of the domain subscales were tested based on Cronbach's α. RESULTS: The Organizational Readiness Tool (ORT) showed adequate psychometric properties and specificity in these eight domains: 1) Current safety/health/well-being programs; 2) Current organizational approaches to safety/health/well-being; 3) Resources available for safety/health/well-being; 4) Resources and readiness for change initiatives to improve safety/health/well-being; 5) Resources and readiness for use of teams in programmatic initiatives; 6) Teamwork; 7) Resources and readiness for employee participation; and 8) Management communication about safety/health/well-being. Acceptable ranges of internal consistency statistics for the domain subscales were observed. CONCLUSIONS: A conceptual model of organizational readiness for change guided development of the Organizational Readiness Tool (ORT), a survey instrument designed to provide actionable guidance for implementing a participatory TWH program. Initial internal consistency was demonstrated following administration at multiple organizations prior to implementation of a participatory Total Worker Health® program.

Double trouble? Clinic-specific risk factors for monozygotic twinning.

OBJECTIVE: To investigate clinic-specific risk factors for monozygotic twinning (MZT) using a large, electronic database. DESIGN: Retrospective case-control study. SETTING: Infertility clinics. PATIENT(S): Using an electronic medical record system, viable clinical pregnancy (confirmation of a gestational sac(s) and presence of at least one fetal pole with a heartbeat on first trimester ultrasound), data were obtained from homologous in vitro fertilization (IVF) cycles after single ET from June 1, 2004, to December 31, 2016. Monozygotic twinning was defined as a pregnancy with two fetal heartbeats on ultrasound with sex concordance at birth. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Risk factors for MZT including cycle type, method of insemination, and method of cryopreservation. RESULT(S): Of the 28,265 IVF cycles that met inclusion criteria over the study period, 8,749 (31.0%) resulted in a viable intrauterine clinical pregnancy. There were 102 (2.7%) MZT in the fresh cycle cohort and 133 (2.7%) in the frozen cycle cohort. Neither cryopreservation nor the method of cryopreservation was a significant risk factor for MZT. However, the use of sequential media was an independent risk factor for MZT in fresh, but not frozen, ETs (odds ratio = 1.72, 95% confidence interval, 1.10-2.68). Significant differences were seen in the incidence of MZT between clinics, and this difference persisted after controlling for known risk factors (clinic 0, reference; clinic 2, odds ratio = 2.22; 95% confidence interval, 1.48-3.32; clinic 3, odds ratio = 1.93; 95% confidence interval, 1.30-2.87). CONCLUSION(S): Differences in MZT rates exist between individual IVF clinics, suggesting that variations in practice patterns may contribute to this event. The present study noted the use of sequential media was an independent risk factor for fresh but not frozen cycles.

The impact of background television on parent-child interaction.

This study investigated the hypothesis that background television affects interactions between parents and very young children. Fifty-one 12-, 24-, and 36-month-old children, each accompanied by 1 parent, were observed for 1 hr of free play in a laboratory space resembling a family room. For half of the hour, an adult-directed television program played in the background on a monaural television set. During the other half hour, the television was not on. Both the quantity and quality of parent-child interaction decreased in the presence of background television. These findings suggest one way in which early, chronic exposure to television may have a negative impact on development.

The Gap Between Tools and Best Practice: An Analysis of Safety Prequalification Surveys in the Construction Industry.

This study characterizes safety prequalification surveys currently in use in the construction industry to identify approaches that include leading indicators of worker safety performance. We collected prequalification surveys available in the public domain from internet searches, construction company websites, published literature, and construction industry partners. We utilized a conceptual framework, based on safety theory and best practices, to categorize survey questions. Fifty-two prequalification surveys were identified containing 112 unique questions. Most included questions related to lagging indicators (83 percent), safety management leadership (75 percent), and worker training (60 percent). Safety management system elements such as hazard prevention and control, program evaluation and improvement, and coordination and communication were notably absent in 90 percent of the surveys. There was little consistency in the surveys available concerning leading indicators of safety. Only a small number of surveys currently in use incorporate all the elements of best practices associated with robust safety management systems.

A sociotechnical systems approach to enhance safety climate in the trucking industry: Results of an in-depth investigation.

The purpose of this study was to develop a methodology that extends safety climate beyond an overall score by using the framework of macroergonomics to examine the entire system in a more comprehensive manner. The study is discussed in two papers: one paper describes the study methodology in detail (Murphy, Robertson, Huang, Jeffries, & Dainoff, in press), and the current paper describes the results of the study. Multiple methods were combined to create a systems approach, and those methods include the critical incident technique, contextual inquiries with functional role diagrams, and affinity mapping. Key informants in the trucking industry identified 19 themes that affect safety. The themes ranged from balancing work and family/personal time, the company's policy vs. practice, respecting the job of the driver, and active listening and meaningful feedback. The most prominent themes were related to the workers and their activities; the internal environment, including psychosocial job design elements; and organizational design. Such information can be used to design interventions to change the safety climate of an organization in order to reduce negative safety outcomes.

A sociotechnical systems approach to enhance safety climate in the trucking industry: Development of a methodology.

The systems approach is increasingly used as a framework within which to examine safety climate. Utilizing a macroergonomics approach to design work systems can help identify aspects of human-technology-organization interfaces that impact workers' perceptions of safety, both positively and negatively. Such an approach also supplements traditional uses of safety climate as a leading indicator of safety and helps expand research toward an approach that can determine problems impacting safety. The purpose of this study was to develop a methodology that extends safety climate beyond just an overall score by using the framework of macroergonomics to examine the entire system in a more comprehensive manner. The proposed methodology can be used as a way to identify gaps in the specific work system, and this information can be used to design interventions to change the safety climate, and ultimately the culture, of an organization in order to reduce negative safety outcomes.

Association between positive and negative affect and musculoskeletal pain among US home health aides.

As the US population ages, there is an expected increase in demand for home health aides (HHAs); therefore, it is important to ensure their occupational well-being. Previous studies have demonstrated associations between negative emotions and musculoskeletal pain. Using survey data collected from 285 HHAs, we characterize the association between affect and musculoskeletal pain. Affect was measured using the Positive and Negative Affect Schedule, while musculoskeletal pain was measured using the Brief Pain Inventory. We found that as positive affect composite score increased, musculoskeletal pain decreased [ß = -0.57, t(124) = -7.01, p < .001]. There was no significant association between the negative affect composite score and musculoskeletal pain. However, several individual moods were associated with decreased or increased pain. These data suggest that some moods may buffer against musculoskeletal pain, while others may predispose HHAs to musculoskeletal pain.

Does talking the talk matter? Effects of supervisor safety communication and safety climate on long-haul truckers' safety performance.

This study examines the distinct contribution of supervisory safety communication and its interaction with safety climate in the prediction of safety performance and objective safety outcomes. Supervisory safety communication is defined as subordinates' perceptions of the extent to which their supervisor provides them with relevant safety information about their job (i.e., top-down communication) and the extent to which they feel comfortable discussing safety issues with their supervisor (i.e., bottom-up communication). Survey data were collected from 5162 truck drivers from a U.S. trucking company with a 62.1% response rate. Individual employees' survey responses were matched to their safety outcomes (i.e., lost-time injuries) six months after the survey data collection. Results showed that the quality of supervisor communication about safety uniquely contributes to safety outcomes, above and beyond measures of both group-level and organization-level safety climate. The construct validity of a newly-adapted safety communication scale was demonstrated, particularly focusing on its distinctiveness from safety climate and testing a model showing that communication had both main and moderating effects on safety behavior that ultimately predicted truck drivers' injury rates. Our findings support the need for continued attention to supervisory safety communication as an important factor by itself, as well as a contingency factor influencing how safety climate relates to safety outcomes.

Musculoskeletal Pain and Interest in Meditation and Yoga in Home Health Aides: Evidence From the Home Health Occupations Musculoskeletal Examinations (HHOME) Study.

Home healthcare aides (HHAs) are a growing U.S. workforce highly susceptible to workplace stressors and musculoskeletal pain. In the present study we: 1) examine the association of musculoskeletal pain to life satisfaction and emotional exhaustion; and 2) characterize interest in meditation and yoga in a sample of HHAs. A nonprobabilistic sample of HHAs employed at home healthcare agencies in Florida, Massachusetts, and Oregon (n = 285 total) completed a self-administered questionnaire with standard survey measures on musculoskeletal pain location, duration, and severity; life satisfaction; emotional exhaustion; and interest in meditation techniques and yoga. Among HHAs responding, 48.4% reported pain in the last 7 days and 46.6% reported pain in the last 3 months. Home healthcare aides who reported current pain and chronic pain had a significant (P < .05) decrease in satisfaction with life score and a significant increase in emotional exhaustion score. The majority of HHAs reported an interest in learning about the benefits (65.6%) and practice (66.4%) of meditation and a willingness to participate in a yoga class (59.2%) or stress management meeting (59.1%). The HHAs reported both acute and chronic musculoskeletal pain that was correlated with lower life satisfaction and greater emotional exhaustion. More efforts are needed to reduce the sources of injury and emotional exhaustion.

Beyond safety outcomes: An investigation of the impact of safety climate on job satisfaction, employee engagement and turnover using social exchange theory as the theoretical framework.

Safety climate, a measure of the degree to which safety is perceived by employees to be a priority in their company, is often implicated as a key factor in the promotion of injury-reducing behavior and safe work environments. Using social exchange theory as a theoretical basis, this study hypothesized that safety climate would be related to employees' job satisfaction, engagement, and turnover rate, highlighting the beneficial effects of safety climate beyond typical safety outcomes. Survey data were collected from 6207 truck drivers from two U.S. trucking companies. The objective turnover rate was collected one year after the survey data collection. Results showed that employees' safety climate perceptions were linked to employees' level of job satisfaction, engagement, and objective turnover rate, thus supporting the application of social exchange theory. Job satisfaction was also a significant mediator between safety climate and the two human resource outcomes (i.e., employee engagement and turnover rate). This study is among the first to assess the impact of safety climate beyond safety outcomes among lone workers (using truck drivers as an exemplar).

Risk factors for a suboptimal response to gonadotropin-releasing hormone agonist trigger during in vitro fertilization cycles.

OBJECTIVE: To identify risk factors for a suboptimal response to gonadotropin-releasing hormone (GnRH) agonist trigger in in vitro fertilization (IVF) cycles. DESIGN: Retrospective cohort study. SETTING: Academic medical center. PATIENT(S): All 424 patients undergoing fresh IVF cycles (n = 500) between August 2007 and June 2013 in whom a GnRH agonist was used as all or part of the ovulation trigger. INTERVENTION(S): GnRH-antagonist-based IVF cycles triggered with leuprolide acetate alone or in combination with low-dose human chorionic gonadotropin. MAIN OUTCOME MEASURE(S): Suboptimal response to GnRH-agonist trigger, as defined by a serum luteinizing hormone (LH) level <15 mIU/mL on the morning after trigger. RESULT(S): The rate of suboptimal response to the GnRH-agonist trigger was 5.2%. Patients with a suboptimal hormone response had lower follicle-stimulating hormone (<0.1 vs. 3.48) and LH (<0.1 vs. 2.51) levels on day 2 of the cycle start, lower LH (0.109 vs. 0.596) on the day of trigger, and required longer stimulation and more gonadotropins than those with an adequate response. Suboptimal responders were also more likely to have irregular menses and be on long-term oral contraception. Patients with an undetectable LH on the day of trigger had a 25% chance of a suboptimal LH surge. In our study cohort, limiting the use of the GnRH-agonist trigger alone to patients with a trigger day LH ≥0.5 would have reduced the rate of suboptimal response from 5.2% to 0.2%. CONCLUSION(S): Long-term hormonal contraception use is an independent risk factor for suboptimal response to GnRH-agonist trigger. Patients with very low endogenous serum LH levels on the day of LH trigger are at increased risk for a suboptimal GnRH-agonist trigger response. Understanding the at-risk phenotype and using trigger day LH as a marker for increased risk of suboptimal GnRH-agonist trigger response can be helpful for individualizing treatment and selecting a safe and efficacious trigger medication for patients undergoing IVF.

The next generation of macroergonomics: integrating safety climate.

To date little research has examined safety climate in relation to macroergonomics and how the two distinct sub-disciplines can be integrated to affect safety outcomes. The purpose of macroergonomics is to design a fully "harmonized" work system that improves numerous aspects of organizational performance and effectiveness, and this is accomplished by incorporating the foundational theoretical framework of sociotechnical systems theory (STS). Two broad subsystems within such a system are the personnel subsystem, the ways individuals perform tasks, and the technological subsystem, the tasks to be performed. Management is an important aspect of the personnel subsystem, and there is a growing body of research regarding supervisors' influence over employee safety. One such area of research is safety climate, which is based on the perception of workers regarding safety and organizational practices. Two major factors of safety climate are management commitment to safety and communication pertaining to safety as a true priority from both top management and direct supervisors. This article describes the conceptual overlaps of macroergonomics and safety climate in order to present a conceptual model that integrates these domains using the framework of mesoergonomics. In conclusion, we discuss how this model can serve as a framework to guide the analysis and design of work systems and subsequent organizational interventions.

External validity of a generic safety climate scale for lone workers across different industries and companies.

PURPOSE: The goal of this study was to examine the external validity of a 12-item generic safety climate scale for lone workers in order to evaluate the appropriateness of generalized use of the scale in the measurement of safety climate across various lone work settings. External validity evidence was established by investigating the measurement equivalence (ME) across different industries and companies. METHOD: Confirmatory factor analysis (CFA)-based and item response theory (IRT)-based perspectives were adopted to examine the ME of the generic safety climate scale for lone workers across 11 companies from the trucking, electrical utility, and cable television industries. RESULTS: Fairly strong evidence of ME was observed for both organization- and group-level generic safety climate sub-scales. Although significant invariance was observed in the item intercepts across the different lone work settings, absolute model fit indices remained satisfactory in the most robust step of CFA-based ME testing. IRT-based ME testing identified only one differentially functioning item from the organization-level generic safety climate sub-scale, but its impact was minimal and strong ME was supported. IMPLICATIONS: The generic safety climate scale for lone workers reported good external validity and supported the presence of a common feature of safety climate among lone workers. The scale can be used as an effective safety evaluation tool in various lone work situations.

Development and validation of safety climate scales for mobile remote workers using utility/electrical workers as exemplar.

PURPOSE: The objective of this study was to develop and test the reliability and validity of a new scale designed for measuring safety climate among mobile remote workers, using utility/electrical workers as exemplar. The new scale employs perceived safety priority as the metric of safety climate and a multi-level framework, separating the measurement of organization- and group-level safety climate items into two sub-scales. The question of the emergence of shared perceptions among remote workers was also examined. METHOD: For the initial survey development, several items were adopted from a generic safety climate scale and new industry-specific items were generated based on an extensive literature review, expert judgment, 15-day field observations, and 38 in-depth individual interviews with subject matter experts (i.e., utility industry electrical workers, trainers and supervisors of electrical workers). The items were revised after 45 cognitive interviews and a pre-test with 139 additional utility/electrical workers. The revised scale was subsequently implemented with a total of 2421 workers at two large US electric utility companies (1560 participants for the pilot company and 861 for the second company). Both exploratory (EFA) and confirmatory factor analyses (CFA) were adopted to finalize the items and to ensure construct validity. Reliability of the scale was tested based on Cronbach's α. Homogeneity tests examined whether utility/electrical workers' safety climate perceptions were shared within the same supervisor group. This was followed by an analysis of the criterion-related validity, which linked the safety climate scores to self-reports of safety behavior and injury outcomes (i.e., recordable incidents, missing days due to work-related injuries, vehicle accidents, and near misses). RESULTS: Six dimensions (Safety pro-activity, General training, Trucks and equipment, Field orientation, Financial Investment, and Schedule flexibility) with 29 items were extracted from the EFA to measure the organization-level safety climate. Three dimensions (Supervisory care, Participation encouragement, and Safety straight talk) with 19 items were extracted to measure the group-level safety climate. Acceptable ranges of internal consistency statistics for the sub-scales were observed. Whether or not to aggregate these multi-dimensions of safety climate into a single higher-order construct (overall safety climate) was discussed. CFAs confirmed the construct validity of the developed safety climate scale for utility/electrical workers. Homogeneity tests showed that utility/electrical workers' safety climate perceptions were shared within the same supervisor group. Both the organization- and group-level safety climate scores showed a statistically significant relationship with workers' self-reported safety behaviors and injury outcomes. IMPLICATIONS: A valid and reliable instrument to measure the essential elements of safety climate for utility/electrical workers in the remote working situation has been introduced. The scale can provide an in-depth understanding of safety climate based on its key dimensions and show where improvements can be made at both group and organization levels. As such, it may also offer a valuable starting point for future safety interventions.