Hospital safety climate and its relationship with safe work practices and workplace exposure incidents.

BACKGROUND: In the industrial setting, employee perceptions regarding their organization's commitment to safety (i.e., safety climate) have been shown to be important correlates to both the adoption and maintenance of safe work practices and to workplace injury rates. However, safety climate measures specific to the hospital setting have rarely been evaluated. This study was designed to develop a short and effective tool to measure hospital safety climate with respect to institutional commitment to bloodborne pathogen risk management programs and to assess the relationship between hospital safety climate and (1) employee compliance with safe work practices and (2) incidents of workplace exposure to blood and other body fluids. METHODS: A questionnaire, which included 46 safety climate items, was developed and tested on a sample of 789 hospital-based health care workers at risk for bloodborne pathogen exposure incidents. RESULTS: A 20-item hospital safety climate scale that measures hospitals' commitment to bloodborne pathogen risk management programs was extracted through factor analysis from the 46 safety climate items. This new hospital safety climate scale subfactored into 6 different organizational dimensions: (1) senior management support for safety programs, (2) absence of workplace barriers to safe work practices, (3) cleanliness and orderliness of the work site, (4) minimal conflict and good communication among staff members, (5) frequent safety-related feedback/training by supervisors, and (6) availability of personal protective equipment and engineering controls. Of these, senior management support for safety programs, absence of workplace barriers to safe work practices, and cleanliness/orderliness of the work site were significantly related to compliance (P<.05). In addition, both senior management support for safety programs and frequent safety-related feedback/training were significantly related to workplace exposure incidents (P<.05). Thus the most significant finding in terms of enhancing compliance and reducing exposure incidents was the importance of the perception that senior management was supportive of the bloodborne pathogen safety program. CONCLUSIONS: Hospital safety climate with regards to bloodborne pathogens can be measured by using a short, 20-question scale that measures 6 separate dimensions. Whereas all 6 dimensions are essential elements of overall safety climate, 3 dimensions are significantly correlated with compliance, and 1 dimension (senior management support) is especially significant with regard to both compliance and exposure incidents. This short safety climate scale can be a useful tool for evaluating hospital employees' perceptions regarding their organization's bloodborne pathogens management program. In addition, because this scale measures specific dimensions of the safety climate, it can be used to target problem areas and guide the development of intervention strategies to reduce occupational exposure incidents to blood and other body fluids.

Simplified amino acid alphabets for protein fold recognition and implications for folding.

Protein design experiments have shown that the use of specific subsets of amino acids can produce foldable proteins. This prompts the question of whether there is a minimal amino acid alphabet which could be used to fold all proteins. In this work we make an analogy between sequence patterns which produce foldable sequences and those which make it possible to detect structural homologs by aligning sequences, and use it to suggest the possible size of such a reduced alphabet. We estimate that reduced alphabets containing 10-12 letters can be used to design foldable sequences for a large number of protein families. This estimate is based on the observation that there is little loss of the information necessary to pick out structural homologs in a clustered protein sequence database when a suitable reduction of the amino acid alphabet from 20 to 10 letters is made, but that this information is rapidly degraded when further reductions in the alphabet are made.

Behavioral-diagnostic analysis of compliance with universal precautions among nurses.

This study used the PRECEDE model (L.W. Green, M.W. Kreuter, S.G. Deeds, & K.B. Partridge, 1980) to examine individual, job-task, and environmental-organizational factors related to compliance with universal precautions (UP) among nurses. Structural equation modeling showed that the hypothesized model did a better job predicting general compliance (R2 = .41) than compliance with personal protective equipment (PPE; R2 = .18). All 3 categories of diagnostic factors (predisposing, enabling, and reinforcing) influenced general compliance, but predisposing factors were relatively unimportant for compliance with PPE. With a set of nested models, the greatest improvement in model fit occurred when the indirect effects of reinforcing factors were added. A positive safety climate may increase the likelihood that the work environment will contain features that enable workers to comply with safe work practices.

Iterative sequence/secondary structure search for protein homologs: comparison with amino acid sequence alignments and application to fold recognition in genome databases.

MOTIVATION: Sequence alignment techniques have been developed into extremely powerful tools for identifying the folding families and function of proteins in newly sequenced genomes. For a sufficiently low sequence identity it is necessary to incorporate additional structural information to positively detect homologous proteins. We have carried out an extensive analysis of the effectiveness of incorporating secondary structure information directly into the alignments for fold recognition and identification of distant protein homologs. A secondary structure similarity matrix based on a database of three-dimensionally aligned proteins was first constructed. An iterative application of dynamic programming was used which incorporates linear combinations of amino acid and secondary structure sequence similarity scores. Initially, only primary sequence information is used. Subsequently contributions from secondary structure are phased in and new homologous proteins are positively identified if their scores are consistent with the predetermined error rate. RESULTS: We used the SCOP40 database, where only PDB sequences that have 40% homology or less are included, to calibrate homology detection by the combined amino acid and secondary structure sequence alignments. Combining predicted secondary structure with sequence information results in a 8-15% increase in homology detection within SCOP40 relative to the pairwise alignments using only amino acid sequence data at an error rate of 0.01 errors per query; a 35% increase is observed when the actual secondary structure sequences are used. Incorporating predicted secondary structure information in the analysis of six small genomes yields an improvement in the homology detection of approximately 20% over SSEARCH pairwise alignments, but no improvement in the total number of homologs detected over PSI-BLAST, at an error rate of 0.01 errors per query. However, because the pairwise alignments based on combinations of amino acid and secondary structure similarity are different from those produced by PSI-BLAST and the error rates can be calibrated, it is possible to combine the results of both searches. An additional 25% relative improvement in the number of genes identified at an error rate of 0.01 is observed when the data is pooled in this way. Similarly for the SCOP40 dataset, PSI-BLAST detected 15% of all possible homologs, whereas the pooled results increased the total number of homologs detected to 19%. These results are compared with recent reports of homology detection using sequence profiling methods. AVAILABILITY: Secondary structure alignment homepage at http://lutece.rutgers.edu/ssas CONTACT: anders@rutchem.rutgers.edu; ronlevy@lutece.rutgers.edu SUPPLEMENTARY INFORMATION: Genome sequence/structure alignment results at http://lutece.rutgers.edu/ss_fold_predictions.

Catastrophe model for the exposure to blood-borne pathogens and other accidents in health care settings.

Catastrophe models, which describe and predict discontinuous changes in system state variables, were used to model the exposure to blood and bodily fluids and more conventional occupational accidents among 1708 health care workers. Workers at three hospitals completed a survey measuring HIV-relevant exposures (needlesticks, cuts, splashes, contact with open wounds), the accident rate for broadly-defined injuries, and several occupationally relevant themes: safety climate, shift work, depression symptoms, work pace, verbal abuse, and professional group membership. A cusp (cubic polynomial) model predicting HIV-relevant exposures specifically was more accurate (R2 = 0.56) than a comparable linear model containing the same variables (R2 = 0.07). Some of the foregoing variables predisposed workers to greater differences in HIV-relevant and general accident exposures: shiftwork, climate, depressive symptoms, and work pace. Other variables governed how close an individual was to a critical threshold where a harmful incident would take place: verbal abuse, professional group membership. Similarly, a cusp model for accident incidents predicted from HIV-relevant exposures and occupational variables was also more accurate (R2 = 0.75) than comparison models. Two variables predisposed the worker to a greater accident risk: depression symptoms and shift work. Four other variables predisposed the worker to lesser accident risk: job satisfaction, safety climate, environmental stressors, and work pace. Compliance with the universal precautions and HIV-related training were not relevant to either of the models.

Tertiary contacts in alpha-lactalbumin at pH 7 and pH 2: a molecular dynamics study.

Molecular dynamics simulations of alpha-lactalbumin were performed under conditions of neutral pH and low pH in order to study the acid-induced molten globule state. Through the use of experimental techniques such as NMR and CD spectroscopy, molten globules have been characterized as being compact intermediates with secondary structure similar to that of the native protein but with tertiary structure that is disordered. The detailed structure of the molten globule state is unknown, however. Through the use of computer simulations we can study the structural changes which occur upon lowering pH. The simulations presented here differ from previous unfolding simulations in two important ways: the electrostatic interactions are treated more accurately than ever before, and artificially high temperatures are not used to force the protein to unfold. Simulations of 880 psec each were run at pH 7 (control simulation) and pH 2. We concentrate on the interesting changes in the tertiary interactions within the protein with lowering of pH. In particular, there is a loss of native tertiary contacts in the beta domain and interdomain region, and a large decrease in interdomain hydrogen bonds.

Worksite health promotion programs in the U.S.: factors associated with availability and participation.

PURPOSE: To examine how the availability of and participation in worksite health promotion programs varies as a function of individual (e.g., age), organizational (e.g., occupation), and health (e.g., high blood pressure) characteristics. Availability of worksite programs was also compared to that reported in two previous national surveys of private companies. DESIGN: Data analyzed were from the 1994 National Health Interview Survey (NHIS), a national cross-sectional probability sample of the U.S. civilian population. SUBJECTS: Five thousand two hundred nineteen NHIS respondents met the inclusion criteria of (1) being currently employed in a company of at least 50 employees, and (2) completing the NHIS section on worksite health promotion. MEASURES: Employees indicated the availability of, and their participation in, 33 different types of worksite programs. National Health Interview Survey data were also available regarding general health, blood pressure, body mass index, and medical conditions. RESULTS: Smoking cessation programs had the highest mean availability (43%), followed by health education programs (31%) and screening tests (31%). Overall, availability of worksite programs appeared comparable to that reported in a recent national survey. Participation ranged from 32% for health education programs to 5% for smoking cessation programs. Compared to availability, participation depended less on individual and organizational characteristics. Healthy employees were not consistently more likely to participate in worksite health promotion programs than nonhealthy employees. CONCLUSIONS: Although availability of worksite health promotion programs remains high, participation by employees in specific types of programs can vary widely. Attempts to increase participation should look beyond individual, health, and organizational variables, to specific features of the work environment that encourage involvement in health promotion activities.

Protein hydration and unfolding--insights from experimental partial specific volumes and unfolded protein models.

BACKGROUND: The partial specific volume of a protein is an experimental quantity containing information about solute-solvent interactions and protein hydration. We use a hydration-shell model to partition the partial specific volume into an intrinsic volume occupied by the protein and a change in the volume occupied by the solvent resulting from the solvent interactions with the protein. We seek to extract microscopic information about protein hydration and unfolding from experimental volume measurements without using computer simulations. We employ the idea that the protein-solvent interaction will be proportional to the surface area of the protein. RESULTS: A linear relationship is obtained when the difference between the experimental protein partial specific volume and its intrinsic volume is plotted as a function of the protein solvent-accessible surface area. The effect of using different protein volume definitions on the analysis of protein volumetric properties is discussed. Volumetric data are used to test a model for the unfolded state of proteins and to make predictions about the denatured state. CONCLUSIONS: The linear relationship between hydration-shell volume change and accessible surface area reflects the similar surface properties (fractional composition of nonpolar, polar and charged surface) among a diverse set of proteins. This linear relationship is found to be independent of how the solution is partitioned into solute and solvent components. The interpretation of hydration shell versus bulk water properties is found to be very model dependent, however. The maximally exposed unfolded protein model is found to be inconsistent with experimental volume changes of unfolding.

Occupational differences in depression and global health: results from a national sample of US workers.

Occupational differences in depression and global health were examined in a sample of 8,486 employed persons who completed the 1987 National Medical Expenditure Survey (NMES). Scores on the depression and global health measures in the NMES were adjusted for age, race, sex, tenure, and hours worked per week, and then grouped according to occupations in the 1980 US Census code. In all, 239 different occupations, distributed across 11 occupational categories, were studied. Results indicated that professional and managerial occupations tended to have healthier scores on both depression and global health. Occupations involving the operation of machines or transportation equipment tended to have poorer scores. These findings are discussed in terms of factors that contribute to occupational differences in well-being, and the need for additional research in which more detailed information concerning working conditions is collected.

Compliance with universal precautions among physicians.

This study characterized and assessed self-reported levels of compliance with universal precautions (UP) among hospital-based physicians, and determined significant factors associated with both compliance and noncompliance. The physicians (n = 322) were a subgroup of a larger study population of hospital-based health care workers recruited from three geographically distinct locations (n = 1746), and were surveyed using a detailed confidential questionnaire that assessed personal, work-related, and organizational factors. Compliance with UP was measured through 11 items that examined how often physicians followed specific recommended work practices. Compliance was found to vary among the 11 items: they were high for certain activities (eg, glove use, 94%; disposal of sharps, 92%) and low for others (eg, wearing protective clothing, 55%; not recapping needles, 56%). Compliance with all items was low (31% to 38%). Stepwise logistic regression revealed that noncompliant physicians were likely to be age 37 or older, to report high work stress, and to perceive a conflict of interest between providing patient care and protecting themselves. Compliant physicians were more likely to be knowledgeable and to have been trained in universal precautions, to perceive protective measures as being effective, and to perceive an organizational commitment to safety.

Stress management in work settings: a critical review of the health effects.

PURPOSE: To review critically the research literature on the health effects of worksite stress-management interventions. SEARCH METHODS: Stress-management interventions were defined as techniques that are designed to help employees modify their appraisal of stressful situations or deal more effectively with the symptoms of stress. Stress-management studies that were worksite based, assessed a health outcome, and were published in the peer-reviewed literature were included in this review. The main search method was the one described in the lead article to this special issue of the JOURNAL, but supplementary sources included prior reviews of the research literature and expert contacts. Sixty-four studies met the criteria for inclusion in this review. SUMMARY OF FINDINGS: A variety of stress-management techniques was used in worksite studies, including muscle relaxation, meditation, biofeedback, cognitive-behavioral skills, and combinations of these techniques. The most common techniques used were muscle relaxation, cognitive-behavioral skills, and combinations of two or more techniques. Outcome measures to evaluate the success of stress interventions included physiologic and psychologic measurements, somatic complaints, and job-related measures. Nearly three-fourths of the studies offered the training to all workers and did not specifically recruit high-stress employees. Over half the studies were randomized control trials, but only 30% conducted posttraining follow-up evaluations. The effectiveness of stress interventions varied according to the health-outcome measure used; some techniques were more effective for psychologic outcomes (e.g., cognitive-behavioral skills), whereas others were more effective for physiologic outcomes (e.g., muscle relaxation). Biofeedback was the least frequent technique used in work settings and also seemed to be the least effective technique. Meditation produced the most consistent results across outcome measures but was used in only six studies. In general, studies using a combination of techniques (e.g., muscle relaxation plus cognitive-behavioral skills) seemed to be more effective across outcome measures than single techniques. CONCLUSIONS: The large number of different stress-management techniques coupled with the wide range of health outcome measures used in stress intervention studies makes it difficult to draw firm conclusions about the efficacy of each technique and each outcome. Also, the quality of the methodology varied substantially among studies. Nevertheless, the most positive results across the various health outcomes were obtained with a combination of two or more techniques. None of the stress interventions was consistently effective in producing effects on job/organization-relevant outcomes, such as absenteeism or job satisfaction. To produce changes on these types of measures, stress interventions will need to alter or modify the sources of stress in the work environment. It can be said that stress management in work settings can be effective in enhancing worker physical and psychologic health, but the choice of which stress-management technique to use should be based on the specific health outcomes that are targeted for change.

A work-systems analysis of compliance with universal precautions among health care workers.

Universal precautions are work practices designed to protect health care workers from occupational exposure to HIV and other bloodborne pathogens. However, despite aggressive dissemination efforts by CDC and regulatory action by OSHA, compliance remains less than satisfactory. This article argues that the minimization of risk from bloodborne pathogens requires a multilevel or work-systems perspective that considers individual, job/task, and environmental/organizational factors. The available literature on universal precautions suggests the potential of such an approach and provides insight into the limited success of current worker-focused mitigation efforts. In particular, specific opportunities exist to develop and apply engineering controls, to improve the design and organization of jobs and tasks, and to create organizations that facilitate and reinforce safe behavior.

Operationalizing theoretical constructs in bloodborne pathogens training curriculum.

This article describes how the protection motivation theory (PMT) was used to inform the production of video curriculum for a bloodborne pathogens training program for hospital nurses. Although hospital nurses are well acquainted with the work practices designed to prevent bloodborne pathogen exposures (universal precautions), there is evidence that they do not always follow them. First, the original PMT is adapted to reflect what is currently known about the role of affect in health behavior prediction. Second, the authors show how the four PMT message constructs-probability of occurrence, magnitude of noxiousness, response efficacy, and self-efficacy-guided the planning, shooting, and editing of the videotapes. Incidental to this process was the operationalization of these message constructs in such a way that affective reactions would result. The results show that this video curriculum successfully aroused negative affect in the target audience. Only by carefully planning and documenting how message constructs are operationalized in health education materials can one be sure of achieving theory-based (and thus the most replicable) message design.

Occupational stress intervention.

The topic of occupational stress has received considerable research attention during the last decade and has emerged as an important occupational safety and health concern. Worker compensation claims for stress-related illnesses, for example, were the fastest growing type of claim in the 1980s, comprising more that 11% of all such claims. Concern over problems associated with occupational stress and their costs has fostered interest in intervention strategies. While specific work stressors and their resulting physical and mental health consequences have been identified, relatively few successful interventions have been documented in the literature. This article discusses primary, secondary, and tertiary interventions efforts in the area of occupational stress and argues for efforts to increase understanding of the occupational stress intervention process.

Compliance with universal precautions among health care workers at three regional hospitals.

OBJECTIVE: To assess and characterize self-reported levels of compliance with universal precautions among hospital-based health care workers and to determine correlates of compliance. DESIGN: Confidential questionnaire survey of 1716 hospital-based health care workers. PARTICIPANTS: Participants were recruited from three geographically distinct hospitals. A stratified convenience sample of physicians, nurses, technicians, and phlebotomists working in emergency, surgery, critical care, and laboratory departments was selected from employment lists to receive the survey instrument. All participants had direct contact with either patients or patient specimens. RESULTS: For this study, overall compliance was defined as "always" or "often" adhering to the desired protective behavior. Eleven different items composed the overall compliance scale. Compliance rates varied among the 11 items, from extremely high for certain activities (e.g., glove use, 97%; disposal of sharps, 95%) to low for others (e.g., wearing protective outer clothing, 62%; wearing eye protection, 63%). Compliance was strongly correlated with several key factors: (1) perceived organizational commitment to safety, (2) perceived conflict of interest between workers' need to protect themselves and their need to provide medical care to patients; (3) risk-taking personality; (4) perception of risk; (5) knowledge regarding routes of HIV transmission; and (6) training in universal precautions. Compliance rates were associated with some demographic characteristics: female workers had higher overall compliance scores than did male workers (25% of female and 19% of male respondents circled "always" or "often" on each of the 11 items, p < 0.05); and overall compliance scores were highest for nurses, intermediate for technicians, and lowest for physicians. Overall compliance scores were higher for the mid-Atlantic respondents (28%) than for those from the Southwest (20%) or Midwest (20%, p = 0.001). CONCLUSIONS: This study supports earlier findings regarding several compliance correlates (perception of risk, knowledge of universal precautions), but it also identifies important new variables, such as the organizational safety climate and perceived conflict of interest. Several modifiable variables were identified, and intervention programs that address as many of these factors as possible will probably succeed in facilitating employee compliance.

Job dimensions associated with severe disability due to cardiovascular disease.

This study explored associations among job activities and disability due to cardiovascular disease by merging national disability data with independently-obtained job activity data. Disability data were taken from a 1978 U.S. health interview survey (n = 9855). Expert ratings of job activities (dimensions) were obtained from a job analysis database (n = 2485 occupations). The two databases were merged such that job dimension data were imputed to each occupation in the disability database. Odds ratios for cardiovascular disability were calculated for scores in the second, third, and fourth quartiles for each of the 32 job dimensions, using scores in the first quartile as the standard. Job dimensions associated with cardiovascular disability were (a) hazardous situations; (b) vigilant work and responsibility for others; (c) exchanging job-related information; and (d) attention to devices. Occupations identified with high scores on these job dimensions included transportation jobs (air traffic controllers, airline pilots and attendants, bus drivers, locomotive engineers, truck drivers), teachers (preschool, adult education), and craftsmen/foremen (machinists, carpenters, and foremen).

Prevention of work-related psychological disorders. A national strategy proposed by the National Institute for Occupational Safety and Health (NIOSH).

The National Institute for Occupational Safety and Health (NIOSH) recognizes psychological disorders as a leading occupational health problem. This document, developed by a NIOSH working group led by the present authors, represents a first attempt to fashion a comprehensive national strategy to protect and promote the psychological health of workers. Roles are identified for industry, labor, government, and academia. Key initiatives include (a) steps to improve working conditions and employee mental health services and (b) increased research and surveillance to advance understanding of the problem. Because work-related psychological disorders appear to be a rapidly developing problem lacking complete definition in terms of scope and etiology, this strategy is not to be considered a final statement of NIOSH policy.