Observational stress factors and musculoskeletal disorders in urban transit operators.

Associations and pathways between observed (rather than self-reported) job stressors and musculoskeletal disorders in 66 transit operators were investigated to determine specific stressors and vulnerable body regions affected, while adjusting for physical workload. Job stressors, defined as barriers to progress with work, comprised 7 categories and the sum of stressors. Outcomes included back and neck pain, low back pain, neck pain, pain of the upper extremities and the lower extremities, and any combination of these. Stressors were significantly associated with the combined musculoskeletal disorders category (odds ratio [OR] = 1.55), back and neck pain (OR = 1.41), low back pain (OR = 1.46), and pain in the lower extremities (OR = 1.44) after controlling for confounders. Five barrier categories had at least 1 significant association with outcomes. Results provide specific intervention targets by avoiding common method variance bias. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Kappa Delta Award. Low back pain and whole body vibration

The investigators describe their multifaceted approach to the study of the relationship between whole body vibration and low back pain. The epidemiologic study was a two center study of drivers and sedentary workers in the United States and Sweden. The vibration exposure was measured in the vehicles. It was found that the career vibration exposure was related to low back, neck, and shoulder pain. However, disability was related to job satisfaction. In vivo experiments, using percutaneous pin mounted accelerometers have shown that the natural frequency is at 4.5 Hz. The frequency response is affected by posture, seating, and seat back inclination. The response appears to be determined largely by the rocking of the pelvis. Electromyographic studies have shown that muscle fatigue occurs under whole body vibration. After whole body vibration exposure the muscle response to a sudden load has greater latency. Vehicle driving may be a reason for low back pain or herniated nucleus pulposus. Prolonged seating exposure, coupled with the whole body vibration, should be reduced for those recovering from these problems. Vibration attenuating seats and correct ergonomic layout of the cabs may reduce the risks of recurrence.     

Anthropometric variables, self-efficacy beliefs, and pain and disability ratings on the isokinetic performance of low back pain patients

OBJECTIVES: This study investigated how age, sex, height, body weight, self-efficacy beliefs, pain, and subjective disability predict the performance of low back pain patients on an isokinetic trunk muscle test. METHODS: One hundred and five patients participated in the study. Dependent variables were isokinetic flexion and extension strength measured as total work done at speeds 50, 100, and 150 degrees/second. RESULTS: The anthropometric measures were poor predictors, height being the only significant one. Body weight and age were of no relevance for the performance. Subjective pain and disability had negative effects on the performance of men, but not of women. Self-efficacy beliefs, i.e., the patient's belief in his or her capability to endure physical activities, was the most powerful predictor. CONCLUSION: For the purpose of validation, standardization, and interpretation of isokinetic performance in low back pain patients, these factors should be taken into account.     

Public transportation driving and disorders of the vertebral spine: subjective evaluation of the risks

Drivers of heavy vehicles can be exposed to risk of spinal disorders due to prolonged fixed postures and vibrations. Thus, ergonomic features which improve the components of the cabin (seat, steering wheel, dashboard) along with correct visibility from the driving position are of primary importance. Also, there are increasingly frequent reports in the literature of the influence of psychosocial factors and stress in back pain. A study was made of 339 volunteers working as public transport drivers; the subjects were administered two questionnaires to collect demographic information, data on past and current spinal disorders, subjective assessment of work organization, ergonomic features of the driving position, and stress. To quantify the prevalence of spinal disorders and their significance compared to a control group consisting of 1200 subjects not exposed to postural risk, account was taken of the threshold criteria recommended by A. Nachemson and the raw prevalence ratios were estimated at specific ages. Comparison of the data revealed no significant prevalence of disorders of the 3 sections of the spine among the exposed in the various age groups. This result, which is apparently in contrast with the data in the literature, is believed to be due to overall improvements in the preventive measures undertaken by the employers. The symptoms reported by some subjects were, however, correlated with incorrect postures due to some not wholly satisfactory ergonomic features and adverse psychosocial factors, with consequent stress.     

Connections between musculoskeletal complaints and personality

Modern research has demonstrated a weak association between level of muscle tension and experience of muscle pain. Anxiety and dysphoric over-responsiveness are the traditional psychogenic risk factors in muscle tension. Results from recent Norwegian research lend support to a more multidimensional causal understanding of muscle tension and of pain. Generally, personality factors were found to be a contributory cause of muscle pain of the neck and shoulders, whereas ergonomic load was found to be of greater significance for low back pain. Personality factors may induce patterns of skeletal muscle activation discrepant with characteristics of the skeletal muscle physiology: Preference for aerobic activities may develop through social learning, whereas the muscles may be genetically biased toward anaerobic activities. Furthermore, personality factors may be challenged by the work setting, and may result in mismatch that provokes muscle pain. Impatient expenditure of effort has appeared as a mediating personality risk factor among workers exposed to high ergonomic load, whereas dysphoric over-responsiveness mediated back pain primarily among staff exposed to high emotional load.     

Unhealthy aggression: Intermittent explosive disorder and adverse physical health outcomes.

Objective: To examine the relationship between Intermittent Explosive Disorder (IED; a psychiatric diagnosis characterized by episodes of affective aggression) and adverse physical health outcomes. Design: A large epidemiological sample drawn from the Collaborative Psychiatric Epidemiological Surveys (N = 10,366), was used to compare participants with a lifetime diagnosis of IED (n = 929) to those without any history of IED (n = 9,437) on demographic variables (age, education, gender, race) common risk factors (smoking status, body mass index, substance use disorders, past accident or injury requiring treatment, major depression) and the presence of 12 adverse health outcomes. Main Outcome Measures: History of heart attacks, coronary heart disease, hypertension, stroke, lung disease, diabetes, cancer, arthritis, back/neck pain, ulcer, headaches, and other chronic pain. Results: Logistic regression analysis controlling for demographic and other risk factors indicated that IED was associated with 9 of the 12 adverse physical health outcomes (coronary heart disease, hypertension, stroke, diabetes, arthritis, back/neck pain, ulcer, headaches, and other chronic pain). Only cancer, heart attacks, and lung disease were not significantly related to IED. Conclusion: IED may be a risk factor for several significant adverse physical health outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Clear cell tumors of the alimentary tract and abdominal cavity

In a population of male workers in two ship maintenance companies (n = 32), a workplace survey was conducted in order to quantify their physical load. Postural load was measured by using the Ovako Working posture Analyzing System. During 7480 observations, working postures, exertion of force and working activities were recorded. Awkward postures of the back occurred in 38% of the worktime, stress on the neck/shoulder region due to one or both arms above shoulder level was present in 25% of the worktime. Forceful exertions during lifting, pushing and pulling activities sometimes exceeded published guidelines for manual material handling. Determinants of physical load could be identified and a hazard evaluation procedure was designed by applying rating schemes to weight various patterns of physical load. Ship maintenance work compared well with other strenuous occupations. Considering the high prevalence of back pain (80%) and neck/shoulder pain (60%), as well as the results of the observation method ergonomic improvements are warranted. Physical load can be reduced by several technical adaptations and applications, and by enlarging task rotation.     

Determinants of isokinetic and psychophysical lifting strength and static back muscle endurance: a study of male monozygotic twins

STUDY DESIGN: Retrospective cohort. OBJECTIVES: To determine the relative contributions of anthropometric factors, physical activity, back and neck pain, overall health, and familial aggregation (the combined effects of genetics and childhood environment) to different measurements of adult back muscle function. SUMMARY OF BACKGROUND DATA: Many methods of muscle testing are employed in the attempt to predict, prevent, treat, and rehabilitate low back pain. Poor correlations between the test results suggest that they are measuring different attributes and have different determinants. METHODS: Muscle function tests, magnetic resonance images, and a detailed interview were obtained in 65 pairs of monozygotic male twins. RESULTS: Familial aggregation was the strongest determinant of isokinetic and psychophysical lifting and static back endurance, explaining 56%, 32%, and 15% of the variances, respectively, beyond that which age alone predicted. Back pain and physical loading in work and leisure explained 2%, 0%, and 23% of the variances. CONCLUSIONS: The combined effects of genetics and childhood environment play a dominant role in determining adult back muscle function. Physical loading at work and leisure, back and neck pain history, overall health, and anthropometric factors had a comparatively minor role, suggesting that the potential of interventions to increase and sustain back muscle function in healthy adults, measured through these tests, may be limited. The relative contributions of constitutional, behavioral, and environmental factors differ substantially in the three tests, and provide insights into what these commonly used tests actually reflect or measure. This knowledge can be used to guide more appropriate selection and interpretation of results of back muscle function tests.     

Weight gain and the risk of developing insulin resistance syndrome

OBJECTIVE: Obesity and weight gain have been associated independently with hypertension, hyperinsulinemia, and dyslipidemia; however, prior research has not looked at the relation between weight gain from early adulthood to middle age and the development of this cluster of risk factors, known as insulin resistance syndrome. RESEARCH DESIGN AND METHODS: The association between weight gain over 30 years (defined as the difference between measured weight in middle age and participant recall of their weight at age 20) and the odds of developing insulin resistance syndrome at middle age was examined in a population-based sample of 2,272 eastern Finnish men. RESULTS: Each 5% increase in weight over the reported weight at age 20 was associated with nearly a 20% greater risk of insulin resistance syndrome by middle age, after adjustment for age and height. Moreover, there was a strong graded association between categories of weight gain and risk of insulin resistance syndrome. Men with weight increases of 10-19%, 20-29%, or > or =30% since age 20 were 3.0, 4.7, or 10.6 times more likely to have insulin resistance syndrome, respectively, by middle age, compared with men within 10% of their weight at age 20. Adjustments for age, height, physical activity, smoking, education, and parental history of diabetes did not alter these findings. CONCLUSIONS: The odds of having developed the hemodynamic and metabolic abnormalities that characterize insulin resistance syndrome by middle adulthood were increasingly higher the greater the weight gain over the preceding 30 years. This study adds to the literature identifying deleterious effects of weight gain from young to middle adulthood.     

Muscle strain during aerial combat maneuvering exercise

BACKGROUND: Little is known about the in-flight muscular strain of fighter pilots. HYPOTHESIS: The purpose of this study was to measure fighter pilots' mean and peak muscular strain during aerial combat maneuvering exercises. The results obtained were compared against existing ergonomic recommendations. METHODS: Six pilots volunteered to serve as test subjects. Their mean age (+/- SD) was 28.5 +/- 5 yr, height 181 +/- 7 cm, and weight 75 +/- 10 kg. They performed one-to-one dog-fight exercises in the morning and in the afternoon. During the flights, the pilots' electromyographic activity (EMC) was measured from the thigh, abdomen, back, and lateral neck. The mean and peak muscular strain for each muscle was calculated as the percentage of maximal voluntary contraction (%MVC). RESULTS: The results showed that the mean muscular strain was 5.2-19.8% MVC, the strain in the lateral neck being the highest. Peak muscular strain (over 50% MVC) occurred almost only during the encounters and usually in the lateral neck. Other muscles were subjected to fewer peak strain episodes; most of these occurred in the back. At least one peak strain episode exceeding 100% MVC was recorded for every muscle studied. The highest peak strain 257% MVC, was measured in the lateral neck. This peak strain episode caused an injury to the lateral neck area, and the flight mission was discontinued. CONCLUSIONS: The mean muscular strain measured in this study was rather low. However, the strain occurring in the lateral neck and the back exceeds the ergonomic recommendations for static work. Especially in the lateral neck, and to some extent in the back, peak strain occurs frequently, in a magnitude that is well above the maximal voluntary contraction; in these areas, the peak strain presents a potential risk of injury and negative health effects. The level and frequent occurrence of peak strain episodes means that fighter pilots' muscular strength and muscular endurance, especially in the neck and shoulder area, are subjected to demands clearly higher than those of the average population.     

Chronological age and age-related cognitive deficits are associated with an increase in multiple types of driving errors in late life.

Objective: Older driver research has mostly focused on identifying that small proportion of older drivers who are unsafe. Little is known about how normal cognitive changes in aging affect driving in the wider population of adults who drive regularly. We evaluated the association of cognitive function and age with driving errors. Method: A sample of 266 drivers aged 70 to 88 years were assessed on abilities that decline in normal aging (visual attention, processing speed, inhibition, reaction time, task switching) and the UFOV?, which is a validated screening instrument for older drivers. Participants completed an on-road driving test. Generalized linear models were used to estimate the associations of cognitive factors with specific driving errors and number of errors in self-directed and instructor navigated conditions. Results: All error types increased with chronological age. Reaction time was not associated with driving errors in multivariate analyses. A cognitive factor measuring speeded selective attention and switching was uniquely associated with the most errors types. The UFOV? predicted blind-spot errors and errors on dual carriageways. After adjusting for age, education, and gender, the cognitive factors explained 7% of variance in the total number of errors in the instructor-navigated condition and 4% of variance in the self-navigated condition. Conclusion: We conclude that among older drivers, errors increase with age and are associated with speeded selective attention, particularly when that requires attending to the stimuli in the periphery of the visual field, task switching, errors inhibiting responses, and visual discrimination. These abilities should be the target of cognitive training. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Perception of difficulties for the back related to assembly work: general findings and impact of back health

The study objective was to describe the perceptions of airplane assemblers on job demand for the back and how back pain modulated these perceptions. One hundred and seventy-six workers answered two questionnaires concerning back pain and the perception of work related difficulties (work activities, work contexts, tools, work positions, efforts). Results show that positions and work contexts are perceived as greater sources of difficulty than efforts or dynamic activities. The duration of a given position is more important than its frequency. Back pain has a significant but complex impact on the perception of difficulty. Assemblers appear to integrate several factors when evaluating their difficulties as opposed to individual aspects, as it is often measured in ergonomic studies. The results have important implications for the measurement of ergonomic factors in the genesis of back pain and illustrates the potential for misclassification and biases in current epidemiologic studies.     

Late morbidity after esophagectomy for cancer: is partial esophagectomy preferred?

BACKGROUND: Several studies have highlighted the problem of back pain among helicopter pilots, but few have controlled for potential confounding factors in their analyses, or sought to examine the effects of back pain on operational readiness and flying performance. There have been no previous studies of the prevalence of back pain among Australian military pilots. METHODS: The prevalence, risk factors, and consequences of low back pain were assessed in a cross-sectional survey of 200 Australian military helicopter pilots by self-completion questionnaire. RESULTS: Responses were received from 131 (66%) of available pilots. The overall prevalence of reported back pain was 64% (95% CI 56%-72%), with a further 28% of pilots describing back discomfort while flying. More than half the pilots (55%) indicated that back pain had interfered with their concentration while flying, with 16% reporting that they had hurried flying missions because of pain. A minority of pilots (7%) had refused to fly because of back problems. After adjusting for age, education, BMI, posture and numbers of hours flown, multiple logistic regression modelling indicated that a prior history of back injury was the most significant predictor of back pain among rotary wing pilots (OR 2.63, 95% CI 1.11-6.23). CONCLUSIONS: We conclude that the prevalence of back pain in Australian military helicopter pilots is unacceptably high and may be limiting operational readiness, pilot performance, flying safety, and pilot health. Urgent attention needs to be given to improved ergonomic design in aircraft, and both back pain prevention and back injury rehabilitation programs.     

Low back pain and its relationship to back strength and physical activity in children

OBJECTIVE: The objective of the study was to determine the occurrence of low back pain and its relationship to back strength and physical activity in children. METHODS AND MATERIALS: The study included 53 boys and 43 girls aged 10 to 19 years from a group of 116 children who had undergone isometric strength testing 4 years previously. No intervention was performed. Each child was asked five questions concerning low back pain. A questionnaire to quantify participation in athletic activities and manual labor was used as the basis for calculation of each child's activity level. Isometric back flexor and extensor strength were measured with the same method used 4 years previously. Statistical analyses were performed with appropriate correction for confounding factors. RESULTS: The frequency of low back pain and the relationship between low back pain and age, between low back pain and back strength, and between low back pain and physical activity were determined. There was a history of low back pain in 51%, and the frequency of low back pain in the past year was 35%. Eight percent of the children had been limited by low back pain, and 7% had seen a doctor for the pain. The first incident of low back pain occurred at a mean age of 12.3 years. The frequencies of a history of low back pain and of low back pain in the past year increased significantly with age (p = 0.02 and 0.01 respectively). Increased physical activity was significantly associated with a history of low back pain (p = 0.03), and increased back flexor strength was significantly associated with a history of low back pain and of low back pain in the past year (p = 0.03 and 0.008, respectively). The rate of low back flexor or strength over 4 years had a significantly positive association with the occurrence of low back pain in the past year (p = 0.008). CONCLUSIONS AND RELEVANCE: Low back pain is common in children, and, in contrast to adults, low back pain in these children was more common with increased physical activity and stronger back flexors. We believe the main causes of low back pain in children are musculotendinous strains and ligamentous sprains.     

Relationships between isoinertial lumbar dynamometry parameters and demographic parameters in chronic low back pain patients

The purpose of this study was to investigate which demographic parameters are most important in relation to lumbar dynamometry performance in patients with chronic low back pain (LBP). Forty-five chronic LBP patients participated in this study. Gender, age, weight and height were determined and a lumbar dynamometry measurement was carried out, using the Isostation B200. Student's t-test, ANOVA techniques and correlation coefficients were used to investigate the relationships between each demographic parameter and lumbar dynamometry performance. Stepwise multiple linear regression analyses were performed afterwards to determine which demographic parameters are most important in relation to lumbar dynamometry performance. Results indicate significant relationships (1) between gender, height, weight and all lumbar dynamometry parameters and (2) between age and three of the six isometric torque parameters. No significant relationship was found between age and maximum velocity parameters. Results of the stepwise multiple linear regression analyses show that the demographic parameters explain 27-47% of the variance in maximum isometric strength parameters and 19-25% of the variance in maximum velocity parameters. Gender is the most important demographic parameter, being related to nearly all maximum isometric torque parameters (percentage explained variance 6-37%) and height is the only important demographic parameter related to the velocity parameters (percentage explained variance 19-25%). Weight and age account for only a small amount of variance in lumbar dynamometry parameters (percentage explained variance 5-7%), meaning that these parameters are non-relevant predictors.     

Contribution of job control and other risk factors to social variations in coronary heart disease incidence

BACKGROUND: The first Whitehall Study showed an inverse social gradient in mortality from coronary heart disease (CHD) among British civil servants--namely, that there were higher rates in men of lower employment grade. About a quarter of this gradient could be attributed to coronary risk factors. We analysed 5-year CHD incidence rates from the Whitehall II study to assess the contribution to the social gradient of psychosocial work environment, social support, coronary risk factors, and physical height. METHODS: Data were collected in the first three phases of examination of men and women in the Whitehall II study. 7372 people were contacted on all three occasions. Mean length of follow-up was 5.3 years. Characteristics from the baseline, phase 1, questionnaire, and examination were related to newly reported CHD in people without CHD at baseline. Three self-reported CHD outcomes were examined: angina and chest pain from the Rose questionnaire, and doctor-diagnosed ischaemia. The contribution of different factors to the socioeconomic differences in incident CHD was assessed by adjustment of odds ratios. FINDINGS: Compared with men in the highest grade (administrators), men in the lowest grade (clerical and office-support staff) had an age-adjusted odds ratio of developing any new CHD of 1.50. The largest difference was for doctor-diagnosed ischaemia (odds ratio for the lowest compared with the highest grade 2.27). For women, the odds ratio in the lowest grade was 1.47 for any CHD. Of factors examined, the largest contribution to the socioeconomic gradient in CHD frequency was from low control at work. Height and standard coronary risk factors made smaller contributions. Adjustment for all these factors reduced the odds ratios for newly reported CHD in the lowest grade from 1.5 to 0.95 in men, and from 1.47 to 1.07 in women. INTERPRETATION: Much of the inverse social gradient in CHD incidence can be attributed to differences in psychosocial work environment. Additional contributions were made by coronary risk factors--mainly smoking--and from factors that act early in life, as represented by physical height.     

Navigation and the mobility of older drivers

OBJECTIVES: Age related difficulties in navigating are believed to restrict driving mobility. A decline in mobility can have negative implications for peoples' well-being and independence. This problem may be more serious than the increased risk of collision that occurs with old age. The aim of this research was to determine the extent to which age-related difficulties in navigating restrict car travel. METHODS: A postal questionnaire survey of 1,186 United Kingdom (U.K.) motorists (aged 21 to 85 years) was conducted to determine more about people's mobility, the restrictions to their driving, and their driving experience. RESULTS: As predicted, respondents were found to report more navigation problems with increasing old age. Hierarchical regression analyses indicated that navigation problems relate to reduced mobility (miles per week, trips per week, and average driving frequency) when controlling for other predictors of mobility (age, gender, employment, health, residential location, fitness, and ability to afford driving). DISCUSSION: This research highlights the need to have better navigational support for drivers, particularly elderly drivers. Improved roads signs and in-vehicle navigation aids are two solutions that might help enhance the mobility of elderly drivers.     

Disc degeneration/back pain and calcification of the abdominal aorta. A 25-year follow-up study in Framingham

STUDY DESIGN: A 25-year follow-up study of 606 members of the population-based Framingham cohort, who had received lateral lumbar radiographs in 1967-1968 and 1992-1993, and completed an interview on back symptoms at the second examination. OBJECTIVES: To evaluate whether calcific lesions in the posterior wall of the abdominal aorta, the source of the feeding arteries of the lumbar spine, are associated with disc degeneration or back pain, which would suggest that ischemia of the lumbar spine leads to disc degeneration. METHODS: The presence of radiographic aortic calcification was ascertained in front of each lumbar segment from L1 through L4, and disc degeneration at intervertebral spaces from L1-L2 through L4-L5. The associations between aortic calcification, disc degeneration, and back pain were tested using logistic regression with adjustment for age and sex. RESULTS: At the baseline examination, aortic calcification was significantly associated with general disc degeneration, that is, disc space narrowing or endplate sclerosis at any lumbar level (odds ratio 1.6; 95% confidence interval 1.0-2.5; P = 0.034). In longitudinal, level-specific analyses, comparing local aortic calcifications with disc degeneration at the matching level, aortic calcifications predicted disc deterioration, that is, a decrease in disc space or appearance of endplate sclerosis, between the examinations (odds ratio 1.5; 95% confidence interval 1.3-1.8; P < 0.001). Furthermore, subjects in whom aortic calcifications developed between the examinations had disc deterioration twice as frequently as those in whom aortic calcifications did not develop (odds ratio 2.0; 96% confidence interval 1.2-3.5; P = 0.013). Also, individuals with severe (Grade 3) posterior aortic calcification in front of any lumbar segment were more likely than others to report back pain during adult life (odds ratio 1.6; 95% confidence interval 1.1-2.2; P = 0.014). CONCLUSIONS: Advanced aortic atherosclerosis, presenting as calcific deposits in the posterior wall of the aorta, increases a person's risk for development of disc degeneration and is associated with the occurrence of back pain.     

Effects of age, system experience, and navigation technique on driving with an advanced traveler information system

This paper explores the effects of age, system experience, and navigation technique on driving, navigation performance, and safety for drivers who used TravTek, an Advanced Traveler Information System. The first two studies investigated various route guidance configurations on the road in a specially equipped instrumented vehicle with an experimenter present. The third was a naturalistic quasi-experimental field study that collected data unobtrusively from more than 1200 TravTek rental car drivers with no in-vehicle experimenter. The results suggest that with increased experience, drivers become familiar with the system and develop strategies for substantially more efficient and safer use. The results also showed that drivers over age 65 had difficulty driving and navigating concurrently. They compensated by driving slowly and more cautiously. Despite this increased caution, older drivers made more safety-related errors than did younger drivers. The results also showed that older drivers benefited substantially from a well-designed ATIS driver interface.     

Crash risks of older drivers: a panel data analysis

Considerable progress has been made on understanding older drivers' safety issues. None the less, findings from previous research have been rather inconclusive. Differences in data and research methodology have been suggested as factors that contribute to the discrepancies in previous findings. One of the methodological limitations is the lack of considering temporal order between events (i.e. the time between onset of medical condition, symptom and crash). Without time-series data, a 'snap-shot' of medical conditions and driving patterns were often linked to more than 1 year--of crash data, hoping to accumulate enough data on crashes. The interpretation of the results from these studies is difficult in that one cannot explicitly attribute the increase in highway crash rates to medical conditions and/or physical limitations. This paper uses a panel data analysis to identify factors that place older drivers at greater crash risk. Our results show that factors that place female drivers at greater crash risk are different from those influencing male drivers. More risk factors were found to be significant in affecting older men's involvement in crashes than older women. When the analysis controlled for the amount of driving, women who live alone or who experience back pain were found to have a higher crash risk. Similarly, men who are employed, score low on word-recall tests, have a history of glaucoma, or use antidepressant drugs were found to have a higher crash risk. The most influential risk factors in men were the number of miles driven, and use of antidepressants.