Biomedical subjects

J R Wilkins

Publications and source records attributed to J R Wilkins.

At least 19 recordsLinked to original sources

PubMed2006

Using participant event monitoring in a cohort study of unintentional injuries among children and adolescents.

OBJECTIVES: We conducted a 3-year cohort study of 407 youths aged 9 to 18 years to develop multivariable risk prediction models of agriculture-related injuries. METHODS: Data were obtained via participant event monitoring, with youths self-reporting injuries and exposures in daily diaries over a 13-week period. We evaluated data quality by comparing injury self-reports with other injury data. RESULTS: Semilogarithmic plots of rates of all unintentional injuries combined (US data from 2000) as well as of agriculture-related injuries (US and Canadian data from 19 previous studies) graphed as a function of injury severity exhibited linearity, as did plots based on the present results. Severity-specific unintentional injury rates were 1.4- to 4.3-times higher than national rates, suggesting that our methodology can significantly reduce injury underreporting. In addition, at each severity level, estimated agriculture-related injury rates were 5.8- to 9.3-times higher than rates from previous national, regional, and state-based studies. CONCLUSIONS: Our approach to participant event monitoring can be implemented with youths aged 9 to 18 years and will yield reliable daily data on unintentional injuries.

Accidents, Occupational↗

PubMed2006

Time-dependent recordkeeping fatigue among youth completing health diaries of unintentional injuries.

PROBLEM: Increasingly, investigators are asking youth to self-report daily activity patterns and health outcomes in diary studies. This study assesses recordkeeping fatigue with respect to data quality and event reporting among youth participating in a health diary study. METHOD: Unintentional injury data were collected during a 13-week longitudinal diary study of Ohio youth exposed to agricultural hazards. Two analyses were conducted using data from 2000. Analysis 1 examined trends in discernable recordkeeping errors (DREs) over the course of follow-up. Analysis 2 assessed trends in injury reporting over follow-up. RESULTS: The percentage of items containing a DRE showed a slight, non-significant decline throughout follow-up. Injury reporting declined significantly (p<0.001) over follow-up. SUMMARY: There was no compelling evidence of respondent fatigue with respect to DREs. The observed decline in injury reporting is problematic because estimates of youth injury incidence in health diary studies may vary depending upon the length of the follow-up period.

Adolescent↗

PubMed2006

Risk of vehicle-pedestrian and vehicle-bicyclist collisions among children with disabilities.

OBJECTIVES: To examine the potential association between disability and risk of vehicle-pedestrian and vehicle-bicyclist collisions among children. METHODS: Data from the 2002 National Transportation Availability and Use Survey for Persons with Disabilities (NTAUSPD) were analyzed. RESULTS: Among 5019 persons who completed the survey, there were a total of 687 children between 5-17 years of age, including 299 respondents with and 388 without disabilities. After controlling for potential confounding variables, children with disabilities were more than five times more likely to have been hit by a motor vehicle as a pedestrian or bicyclist than children without disabilities (adjusted OR = 5.53, 95% confidence interval (CI): 1.43-21.41). For all children, regardless of their disability status, children who reported having some difficulty with traffic had a significantly higher risk of collisions (adjusted OR = 50.71, 95% CI: 7.35-349.86). The most commonly reported traffic difficulties for all children with and without disabilities were "Too few or missing sidewalks/paths," "Do not know when it's safe to cross," and "Insensitive/unaware drivers." CONCLUSIONS: Existing effective transportation safety interventions should be effective in reducing the risk of vehicle-pedestrian and vehicle-bicyclist collisions in children with disabilities. Future research and safety interventions should focus on how to promote the use of existing effective transportation safety interventions among children with disabilities and their families.

Accidents, Traffic↗

PubMed2006

Protecting young workers in agriculture: participation in tractor certification training.

Tractor-related injuries among youth are an important public health problem. The major objectives of this study were to (1) provide a rigorous estimate of the number of youth operating tractors in Ohio and (2) assess the extent to which these youth are participating in federally mandated tractor safety training. A self-administered questionnaire was completed by approximately 4,000 students ages 14 or 15 years who were enrolled in a stratified cluster sample of 99 Ohio schools. Almost one-third of the youth (30%) reported having operated tractors, with 19% having operated a tractor on a farm not owned by a parent or guardian. More than half of the youth (52%) reported having operated a tractor and/or other hazardous machinery, with 25% having operated the machinery on a farm not owned or operated by a parent or guardian. Extrapolating from 4-H records and Ohio census data, fewer than 1% of the youth who are operating tractors or other hazardous machinery have participated in tractor certification training. Increasing participation in mandated training may be an important step in protecting the health of our nation's young agricultural workers.

Accidents, Occupational↗

PubMed2006

Escalator-related injuries among children in the United States, 1990-2002.

OBJECTIVE: We describe the epidemiology of escalator-related injuries among children 0 to 19 years of age in the United States, with a focus on the pediatric population that is younger than 5 years. METHODS: We conducted a retrospective analysis of data from the National Electronic Injury Surveillance System of the US Consumer Product Safety Commission. Reported cases were used to project national estimates and rates of escalator-related injuries in the United States. The analysis included all patients who were 0 to 19 years of age in the National Electronic Injury Surveillance System database and were seen in an emergency department for an escalator-related injury during the 13-year period 1990-2002. RESULTS: There were an estimated 26000 escalator-related injuries among children who were 0 to 19 years of age in the United States during 1990-2002, yielding an average of 2000 of these injuries annually (rate = 2.6 per 100,000 population per year). The mean age was 6.5 years at the time of injury, and 53.4% of the patients were male. When comparing cases by 5-year age groups, children who were younger than 5 years had the highest estimated number of injuries (12000), as well as the highest annual escalator-related injury rate (4.8 per 100000). The most common mechanism of injury for all age groups was a fall, accounting for 13000 (51.0%) injuries. Entrapment accounted for 29.3% of all injuries and 36.5% of injuries among children who were younger than 5 years. Six percent (723) of injuries to children who were younger than 5 years involved a stroller, with most injuries occurring when a child fell out of the stroller while on the escalator. The most common body part injured for all ages was the leg, accounting for 27.7% of all injuries. Among children who were younger than 5 years, the hand was the most common injury site (40.6%), with hand injuries frequently occurring as a result of entrapment (72.4%). A laceration was the most common type of injury, accounting for 47.4% of escalator-related injuries. Amputations and avulsions were uncommon; however, 71.4% (595 of 833) occurred among children who were younger than 5 years. CONCLUSIONS: There was a disproportionate number of escalator-related injuries among children who were younger than 5 years. Entrapment occurred more frequently among children who were younger than 5 years than in any other age group, which may explain the increased number of hand injuries in this age group. Escalator designs that reduce the gap between the steps and sidewall or shield against access to the gap may decrease entrapment risk. Young children should be supervised properly and should not be transported in a stroller while riding on an escalator. All passengers should use caution and remain alert when riding an escalator to avoid injuries related to falls or entrapment. Additional research is needed to determine the relationship among passenger behavior, escalator design, and escalator-related injury.

Accidental Falls↗

PubMed2005

Self-reported symptoms of neurotoxicity and agricultural injuries among Ohio cash-grain farmers.

BACKGROUND: In 1993, the Ohio Farm Family Health and Hazard Surveillance Program (OFFHHSP) was initiated to assess the health status of cash-grain farmers and their families. The objective of this study was to examine the postulated relationship between symptoms of neurotoxicity and risk of agriculture-related injury among Ohio cash-grain farmers. METHODS: A reanalysis of the data from a previously published case-control study of cash-grain farmers [Crawford et al. (1998) Am J Ind Med 34:588-599] was performed. The Principal Operator (PO) of each farm was asked to complete a self-administered questionnaire which included items about injuries experienced during the past year. A section of the questionnaire contained a 24-item instrument ("Q24") that queried symptoms of neurotoxicity experienced during the previous 12 months. Design-based multiple logistic regression analyses were conducted to evaluate associations between neuropsychological subsets ("domains") of the 24-item instrument and injury risk among the white male POs (who accounted for >99% of all POs). RESULTS: Significantly elevated odds ratios (ORs) were found in 8 of 11 domains. POs answering in the affirmative to the single item "Have you been bothered by lack of coordination or loss of balance?" were 3.12 times more likely to have reported an injury than POs responding negatively (95% CI 1.68-5.81). CONCLUSIONS: Farmers with higher scores on several Q24 domains, and for particular questionnaire items, appear to be at increased risk of agricultural injury.

Accidents, Occupational↗

PubMed2005

Obesity and risk of nonfatal unintentional injuries.

BACKGROUND: Obesity is recognized as a risk factor for multiple chronic diseases. Yet, it is unclear whether obesity is also associated with an increased risk of nonfatal unintentional injury. METHODS: A population-based survey was conducted among adults aged > or = 18 years from January 1999 through October 2000. The relationship was investigated between body mass index (BMI), defined as weight in kilograms divided by the square of the height in meters (kg/m2), and risk of nonfatal unintentional injuries among 2575 respondents aged > or = 20 years by comparing percentage of adults between obese and nonobese respondents who had injuries. Multivariate logistic regression further examined this relationship by controlling for confounding demographics. RESULTS: A total of 370 respondents reported injuries in the previous year. We observed a linear dose-response trend among women. An estimated 7.0% of underweight individuals (BMI <18.5) reported injuries. In contrast, 26.0% of men and 21.7% of women with a BMI > or = 35.0 reported injuries. The odds ratio of injuries for individuals with a BMI > or = 35.0 was 2.00 (95% confidence interval=1.07-3.74, p<0.05) after controlling for gender, age, education level, marital status, family poverty status, and area of residence. CONCLUSIONS: A marginally significant association between extreme obesity and elevated risk of injuries was observed. Efforts to promote optimal body weight may reduce not only the risk of chronic diseases but also the risk of unintentional injury among overweight and obese individuals.

Adolescent↗

PubMed2004

Physical demands and low-back injury risk among children and adolescents working on farms.

Little information currently exists regarding the risk of low-back disorders among youth who perform physically demanding farm activities. Thus, afield study was conducted in which children and adolescents who engage in farm work were recruited, fitted with a lumbar motion monitoring system, and then observed performing their usual chores. The lumbar motion monitor was used to record the trunk movements required while youth were performing routine manual material handling tasks on a farm. Workplace factors and motions from both males and females were recorded on over 40 farm tasks, such as feeding animals, lifting bales of hay and straw, and other miscellaneous farm chores. Although the sample size and number of observations in this study were small, the results showed that the magnitude of several work-related factors, such as weight and horizontal moment arm, and trunk motions for many farm activities were equal to or greater than those associated with high injury risk jobs previously assessed in industrial workplaces. In this study, we quantified the physical demands of tasks performed by children and adolescents on farms. In addition, the specific farm chores more likely to load the spines of youth and thereby contribute to musculoskeletal injury were identified.

Adolescent↗

PubMed2003

Prevalence of ROPS--equipped tractors and farm/farmer characteristics.

Data were collected on tractor safety status and the prevalence of ROPS as part of the Ohio Farm Family Health and Hazard Surveillance Program (FFHHSP) "walk-around" hazard assessments of cash grain farms in central Ohio. Principal operator (PO) characteristics thought a priori to have a possible association with ROPS utilization included age, education, percent time spent farming, total years in agriculture, and previous training in occupational injury prevention. Farm characteristics of interest were farm size, acres of cropland in use, sales value during the past 12 months, and current number of farm workers. Descriptive and logistic regression analyses were conducted to evaluate potential associations between these factors and ROPS utilization patterns. Of 1,044 tractors encountered on 306 farms, 359 (34.4%) were equipped with ROPS, 29 (9.5%) had nothing but ROPS-equipped tractors, and 117 (38.2%) did not have any ROPS-equipped tractors. The absence/presence of ROPS-equipped tractors in our sample was found to vary by several factors, and over a wide range. Results of invariable logistic regression analyses (excluding the relatively small number of tractors manufactured after 1985) indicated that younger POs with at least a high school education who spent more than half their time working in agriculture, employed three or more workers, had 500 or more acres of total farm land and cropland in use, and had a 12-month sales value exceeding $250,000 were more likely to have at least one ROPS-equipped tractor on their farms. However, time spent farming, number of workers, and the 12-month sales value were not strongly predictive in multivariable models. Although more than 20% of the POs in our sample reported having had training in occupational injury prevention, this factor had essentially no value in predicting the absence/presence of ROPS-equipped tractors on their farms. The results of this study illustrate the need for interventions to encourage ROPS retrofitting that target POs with less education and who work on smaller and less productive farms. However, the low overall ROPS utilization rates suggest that all farmers could benefit from intervention efforts.

Accidents, Occupational↗

PubMed1999

Prevalence of chronic respiratory symptoms among Ohio cash grain farmers.

BACKGROUND: The prevalence of chronic cough, chronic phlegm, dyspnea, and non-cold wheeze was estimated from a mixed-mode survey of Ohio cash grain farmers in 1993. METHODS: Personal characteristics of the principal operators (POs) such as age and cigarette smoking, in addition to selected farm characteristics and relevant medical and work history factors potentially associated with both exposure to respiratory irritants and subsequent respiratory symptoms were considered. RESULTS: The overall design-adjusted prevalences (and the corresponding 95% confidence intervals (CIs) were: 9.4% (7.6-11.1%) for chronic cough, 10.8% (9.0-12.6%) for chronic phlegm, 16.2% (14.1-18.3%) for dyspnea, and 8.1% (6.4-9.8%) for non-cold wheeze. In univariate and multivariate analyses, smoking status was found, not surprisingly, to be the strongest predictor of increased symptom prevalence compared to all other factors. Other non-occupational factors found associated with increased symptom prevalence include age (cough, phlegm, dyspnea) and pet allergy (non-cold wheeze). Occupational factors found at least weakly associated with increased symptom prevalence include lifetime hours of cab tractor operation (cough); percent time spent farming (phlegm); having livestock other than cattle, cows, and calves (dyspnea); acres of corn for silage or green chop (cough); acres of alfalfa hay (non-cold wheeze); and personal involvement with pesticides (cough). CONCLUSIONS: Symptom prevalences reported here are consistent with previous findings from studies of other groups of farmers. Results pertaining to factors found associated with symptom prevalences should be interpreted in light of several sources of potential bias.

Adult↗

PubMed1999

Evaluation of focal defects of the nerve fiber layer using optical coherence tomography.

OBJECTIVE: To analyze glaucomatous eyes with known focal defects of the nerve fiber layer (NFL), relating optical coherence tomography (OCT) findings to clinical examination, NFL and stereoscopic optic nerve head (ONH) photography, and Humphrey 24-2 visual fields. DESIGN: Cross-sectional prevalence study. PARTICIPANTS: The authors followed 19 patients in the study group and 14 patients in the control group. INTERVENTION: Imaging with OCT was performed circumferentially around the ONH with a circle diameter of 3.4 mm using an internal fixation technique. One hundred OCT scan points taken within 2.5 seconds were analyzed. MAIN OUTCOME MEASURES: Measurements of NFL thickness using OCT were performed. RESULTS: In most eyes with focal NFL defects, OCTs showed significant thinning of the NFL in areas closely corresponding to focal defects visible on clinical examination, to red-free photographs, and to defects on the Humphrey visual fields. Optical coherence tomography enabled the detection of focal defects in the NFL with a sensitivity of 65% and a specificity of 81%. CONCLUSION: Analysis of NFL thickness in eyes with focal defects showed good structural and functional correlation with clinical parameters. Optical coherence tomography contributes to the identification of focal defects in the NFL that occur in early stages of glaucoma.

Cross-Sectional Studies↗

PubMed1999

Agricultural hazard data from a population-based survey of cash grain farms: Ohio observations.

In response to congressional concerns, the National Institute for Occupational Safety and Health (NIOSH) initiated a multistate agricultural surveillance effort in 1990. The Farm Family Health and Hazard Surveillance (FFHHS) program involved separate population-based surveillance efforts by six state agencies or universities which gathered health and hazard data on farm operators and farm families. The results of the Ohio program are presented as an example of the data collection capabilities developed during the course of this project, which include the application of these data in documenting the prevalence of specific agricultural occupational hazards as well as the current attitudes of agricultural operators toward control and elimination of safety and health hazards. Specifically, three operationally defined areas of hazard audit (Structures, Landscape, and Mobile Equipment) are examined for the prevalence of such safety hazards as potential electrical shock, slippery or badly maintained walkways, inadequate chemical and fuel storage, and missing farm equipment moving-part guards. Questionnaire survey response examples are presented as an indication of farm operator attitudes toward safety and health training, on-site professional service access, and use of personal protective equipment. Current plans for data use and distribution, and the potential applications of the data as an occupational safety and health tool are also discussed.

Agricultural Workers' Diseases↗

PubMed1998

Occupational factors and reproductive outcomes among a cohort of female veterinarians.

OBJECTIVE: To estimate absolute and relative risks of preterm delivery (PTD) and small-for-gestational-age (SGA) births among a cohort of female veterinarians in relation to selected occupational factors, including clinical practice type (CPT). DESIGN: Retrospective cohort survey. SAMPLE POPULATION: 2,997 female graduates from US veterinary colleges between 1970 and 1980. PROCEDURE: Relevant health and occupational data were collected through a self-administered mail questionnaire with telephone follow-up of nonrespondents. Absolute and relative risks of PTD and SGA births were estimated in relation to maternal CPT at the time of conception and exposure to 13 occupational factors. Attempts were made to control confounding by use of multiple logistic regression analyses. RESULTS: Absolute and relative risks of PTD were highest for veterinarians employed in exclusively equine clinical practice. Although several increased, none of the CPT-specific relative risk estimates were significantly different from the null value of 1. Exposure-specific analyses indicated that occupational involvement with solvents among exclusively small animal practitioners was associated with the highest relative risk of PTD. A small number of SGA births limited information that could be obtained from these analyses. Overall absolute risks of PTD and SGA births among cohort members were much lower in comparison with the general female population. CLINICAL IMPLICATIONS: Given the large number of women currently practicing and entering the profession of veterinary medicine, clinical tasks associated with potential reproductive hazards should be approached with heightened awareness and increased caution, especially activities that may involve exposure to solvents.

Cohort Studies↗

PubMed1998

A cross-sectional case control study of work-related injuries among Ohio farmers.

The agricultural industry has consistently been ranked among the most hazardous in the U.S. To date, few analytic studies of occupational injury among farm operators and workers have been conducted. A case control study was undertaken to investigate risk factors for agricultural work-related injury among Ohio farm operators. Cases were selected from among 1,793 respondents to a questionnaire administered during the first phase of the NIOSH-sponsored Ohio Farm Family Health and Hazard Study (OFFHHS). Analysis consisted of description of the injury experience of the sample as a whole, followed by logistic estimation of prevalence odds ratios (pORs) measuring the effect of potential risk factors on injury risk. The case series consisted of 90 white male principal operators (POs) injured doing farm work in the 12 months prior to questionnaire completion. Controls consisted of 1,475 white male POs who reported no injuries. The overall rate of injury was 5 per 100 person-years. The most notable result is the relationship between self-reported neurotoxic symptoms and injury, suggesting those with more reported symptoms were at greater risk of injury. The crude OR, when compared to the reference score of < or = 27, increased from 1.74 (95% CI = 0.60-5.09) in the 28-30 category, to 1.89 (95% CI = 0.71-5.03) in the 31-35 category, to 2.96 (95% CI = 1.10-7.96) in the highest category of test score. The P value for trend was 0.0218. These associations largely persisted after controlling for potential confounders with multiple logistic regression. Risk was inversely related to age. The results show marked increases in risk of injury associated with farmers younger than 30 and increased severity of self-reported neurological symptoms, controlling for potential confounding.

Accidents, Occupational↗

PubMed1998

Topography of diabetic macular edema with optical coherence tomography.

OBJECTIVE: This study aimed to develop a protocol to screen and monitor patients with diabetic macular thickening using optical coherence tomography (OCT), a technique for high-resolution cross-sectional imaging of the retina. DESIGN: A cross-sectional pilot study was conducted. PARTICIPANTS: A total of 182 eyes of 107 patients with diabetic retinopathy, 55 eyes from 31 patients with diabetes but no ophthalmoscopic evidence of retinopathy, and 73 eyes from 41 healthy volunteers were studied. INTERVENTION: Six optical coherence tomograms were obtained in a radial spoke pattern centered on the fovea. Retinal thickness was computed automatically from each tomogram at a total of 600 locations throughout the macula. Macular thickness was displayed geographically as a false-color topographic map and was reported numerically as averages in each of nine regions. MAIN OUTCOME MEASURES: Correlation of OCT with slit-lamp biomicroscopy, fluorescein angiography, and visual acuity was measured. RESULTS: Optical coherence tomography was able to quantify the development and resolution of both foveal and extrafoveal macular thickening. The mean +/- standard deviation foveal thickness was 174 +/- 18 microns in normal eyes, 179 +/- 17 microns in diabetic eyes without retinopathy, and 256 +/- 114 microns in eyes with nonproliferative diabetic retinopathy. Foveal thickness was highly correlated among left and right eyes of normal eyes (mean +/- standard deviation difference of 6 +/- 9 microns). Foveal thickness measured by OCT correlated with visual acuity (r2 = 0.79). A single diabetic eye with no slit-lamp evidence of retinopathy showed abnormal foveal thickening on OCT. CONCLUSIONS: Optical coherence tomography was a useful technique for quantifying macular thickness in patients with diabetic macular edema. The topographic mapping protocol provided geographic information on macular thickness that was intuitive and objective.

Adult↗

PubMed1997

Comparing dietary recall data for mothers and children obtained on two occasions in a case-control study of environmental factors and childhood brain tumours.

BACKGROUND: Food frequency questionnaires (FFQ) have been widely used in epidemiological studies of dietary factors, despite persistent questions about the quality of the data they generate. To address concerns about the influence of disease status on dietary recall, we examined the temporal consistency of dietary recall data obtained in a case-control study of environmental factors and childhood brain tumours. METHODS: On two occasions separated by approximately 4.5 years, the mothers of children with brain tumours and healthy matched controls were asked about their diets during pregnancy and their children's diets prior to diagnosis. Forty-five case and 60 control mothers completed both FFQ for themselves and/or their children. Daily dietary intakes of substances related to dietary N-nitroso compounds were estimated from the responses to each of the questionnaires and compared. The dietary intakes of the cases were also compared to their matched controls. RESULTS: The changes in estimated dietary intakes from the first to the second questionnaire administration were similar in both groups of mothers, indicating negligible case-control differences in healthy individuals recalling their own diets. Control mothers reported for their children a higher intake of the index foods on the second questionnaire than on the first while estimated intakes for the case children were lower the second time compared to the first. Significant case-control differences among the children were seen for the majority of dietary components examined. CONCLUSIONS: The results suggest that the magnitude and direction of errors in dietary recall data can vary by disease status, and further suggest that reliance on retrospective reports of children's diets may be inappropriate in a case-control study.

Adolescent↗

PubMed1997

Needlestick injuries among female veterinarians: frequency, syringe contents and side-effects.

In a mixed-mode survey of all 1970-80 female graduates of all US veterinary colleges, information was obtained regarding several health, personal and occupational factors including data on occupational needlestick events. Among the 2,532 survey respondents, 1,620 reported one or more needlesticks after graduation from veterinary college (64.0% of all respondents). A total of 2,663 stick events were reported, although the descriptions of each puncture event varied in quality/completeness, probably due in large part to their retrospective nature. Substances most often injected include vaccines, antibiotics, anaesthetics and animal blood. Of the 438 sticks resulting in at least one side-effect (16.4% of all sticks), 337 were classified as mild and localized at the site of injection (12.4% of all sticks, approximately 77% of sticks producing a side-effect), with 18 characterized as severe and systemic (0.7% of all sticks, approximately 4% of sticks producing a side-effect). One accidental self-injection of a prostaglandin compound resulted in a spontaneous abortion, heightening awareness that occupational needlesticks may also represent a serious human reproductive health hazard. The estimated overall needlestick injury rate for this group of health care professionals was 9.3 sticks per 100 person-years (PYs) of practice, comparable to reported rates among health care workers such as nurses, laboratory technicians and hospital housekeeping staff. Accounting for underreporting of the stick events, the actual injury rate is likely to be at least 20 sticks per 100 PYs. When stick rates were estimated by clinical practice type (small animal, large animal and mixed practice), all-small-animal and mixed-practice veterinarians demonstrated the highest rates, with all-large-animal practitioners demonstrating a rate lower by about 40%.

Anesthetics↗

PubMed1997

Mixed-mode survey of female veterinarians yields high response rate.

In a recent study of female veterinarians, a subgroup of health professionals growing rapidly in number, the authors employed a mixed-mode survey design in targeting the cohort of women graduating from all US veterinary colleges during the 11-year period 1970-80 (n = 2,997). The questionnaire elicited information on a variety of health and occupational factors and required 35 minutes on average to complete. In the first stage, a modified version of Dillman's Total Design Method for mailed, self-administered questionnaires was employed, yielding a response rate of 82.9%. In the second stage, a telephone interview of all mail non-respondents was attempted, yielding a response rate here of only 30.1%, but increasing the overall response rate among those contacted to 90.2%. Non-respondents differed little from mail (early) or telephone (late) respondents with respect to year of graduation and geographic region of veterinary college attendance. Gentle probing of telephone non-respondents suggested the personal nature of some questions and the amount of time required to answer all questions were the main reasons they chose not to participate. It therefore appears that conventional survey techniques may be successfully employed in health studies of health professionals, particularly if issues of great concern to the target population are addressed.

Bias↗