It's Your Game Keep It Real in South Carolina: A Group Randomized Trial Evaluating the Replication of an Evidence-Based Adolescent Pregnancy and Sexually Transmitted Infection Prevention Program.

OBJECTIVES: To evaluate the effectiveness of an evidence-based HIV/sexually transmitted infection (STI)/pregnancy prevention program for middle schools implemented by school staff in South Carolina. METHODS: Twenty-four schools, representing 3143 youths, participated in a randomized trial from 2011 to 2014. Students completed surveys before programming (fall of seventh grade), after completing the 2-year It's Your Game…Keep It Real program (spring of eighth grade), and 1-year postprogram (spring of ninth grade). RESULTS: There was no statistically significant effect on initiation of vaginal sex between baseline and eighth grade. Significantly fewer students in the comparison condition reported initiating sex at ninth grade, relative to the intervention condition. No group differences existed on other behavioral outcomes that addressed sexual activity in the past 3 months at ninth grade. Seven of 26 psychosocial outcomes (3 knowledge, 1 attitude, 1 self-efficacy, 2 personal limits) were positively affected at eighth grade; 4 remained significant at ninth grade. CONCLUSIONS: The original studies' behavioral effects were not replicated in this population, possibly as a result of this being an effectiveness trial instead of an efficacy trial, counterfactual exposure design issues, or postprogram exposure to evidence-based programming.

Sustaining Teen Pregnancy Prevention Programs in Schools: Needs and Barriers Identified by School Leaders.

BACKGROUND: To reduce teen pregnancy rates, prevention programs must be consistently available to large numbers of youth. However, prevention efforts have been historically conducted with little emphasis on ensuring program sustainability. This study examined the needs and barriers to sustaining teen pregnancy prevention (TPP) programming in schools after grant funding has ended, as identified by school leadership. METHODS: A total of 11 qualitative interviews were conducted between June and September 2012 with middle school leaders from 11 schools involved in current implementation of a TPP program in South Carolina. Interviews were audio-recorded, transcribed verbatim, and thematically coded. RESULTS: Identified needs and barriers to sustainability varied across schools. Common barriers to program sustainability included: lack of materials and supplies, insufficient funding (at the school and district level), lack of support and/or parental opposition, and other school/district priorities. School leaders also identified several needs to continue TPP programming, including: continued funding, trainings, outcome/effectiveness data to support the program, and regularly updated curriculum. CONCLUSION: Schools with greater perceived needs and barriers may be less likely to sustain. Knowledge gained through this research may be used to inform future interventions and sustainability planning efforts, allowing us to maximize prevention programming.

Using data to improve fidelity when implementing evidence-based programs.

In fall 2011, the South Carolina Campaign to Prevent Teen Pregnancy (SC Campaign), with funding from Office of Adolescent Health, began replicating an evidence-based curriculum, It's Your Game, Keep It Real in 12 middle schools across South Carolina. Fidelity of the curriculum was monitored by the use of lesson fidelity logs completed by curriculum facilitators and lesson observation logs submitted by independent classroom observers. These data were monitored weekly to identify possible threats to fidelity. The innovative model Fidelity Through Informed Technical Assistance and Training was developed by SC Campaign to react to possible fidelity threats in real time, through a variety of technical assistance modalities. Fidelity Through Informed Technical Assistance and Training guided the 55 hours of technical assistance delivered by the SC Campaign during the first year of It's Your Game, Keep It Real implementation to 18 facilitators across 12 SC middle schools, and achieved 98.4% curriculum adherence and a high quality of implementation scores.

Enhancing teen pregnancy prevention in local communities: capacity building using the interactive systems framework.

Getting To Outcomes (GTO), an innovative framework for planning, implementing, evaluating, and sustaining interventions has been shown to be effective in helping community-based organizations (CBOs) introduce science-based approaches into their prevention work. However, the Interactive Systems Framework (ISF) suggests that adopting innovations like GTO requires a significant amount of capacity building through training and technical assistance (T/TA). In this study, 11 CBOs and three schools in South Carolina entered into a 3 year program of intense and proactive T/TA based on the ISF to learn how to apply an adaptation of GTO (Promoting Science-Based Approaches-Getting To Outcomes, PSBA-GTO) to their teen pregnancy prevention programs. Using semi-structured interviews, the partnering organizations were assessed at three points in time, pre-T/TA, 12 months, and post T/TA (30 months) for their performance of the steps of GTO in their work. The seven organizations which participated in T/TA until the end of the project received an average of 76 h of TA and 112 h of training per organization. Interview results showed increased performance of all 10 steps of PSBA-GTO by these organizations when conducting their teen pregnancy programs. These results suggest targeted and proactive T/TA can successfully bridge the gap between research and practice by using a three part delivery system, as prescribed in the ISF, which relies on an intermediary prevention support system to ensure accurate and effective translation of research to the everyday work of community-based practitioners.

Development of a retrospective job exposure matrix for PCB-exposed workers in capacitor manufacturing.

OBJECTIVES: Polychlorinated biphenyls (PCBs) are considered probable human carcinogens by the International Agency for Research on Cancer and one congener, PCB126, has been rated as a known human carcinogen. A period-specific job exposure matrix (JEM) was developed for former PCB-exposed capacitor manufacturing workers (n=12,605) (1938-1977). METHODS: A detailed exposure assessment for this plant was based on a number of exposure determinants (proximity, degree of contact with PCBs, temperature, ventilation, process control, job mobility). The intensity and frequency of PCB exposures by job for both inhalation and dermal exposures, and additional chemical exposures were reviewed. The JEM was developed in nine steps: (1) all unique jobs (n=1,684) were assessed using (2) defined PCB exposure determinants; (3) the exposure determinants were used to develop exposure profiles; (4) similar exposure profiles were combined into categories having similar PCB exposures; (5) qualitative intensity (high-medium-low-baseline) and frequency (continuous-intermittent) ratings were developed, and (6) used to qualitatively rate inhalation and dermal exposure separately for each category; (7) quantitative intensity ratings based on available air concentrations were developed for inhalation and dermal exposures based on equal importance of both routes of exposure; (8) adjustments were made for overall exposure, and (9) for each category the product of intensity and frequency was calculated, and exposure in the earlier era was weighted. RESULTS: A period-specific JEM modified for two eras of stable PCB exposure conditions. CONCLUSIONS: These exposure estimates, derived from a systematic and rigorous use of the exposure determinant data, lead to cumulative PCB exposure-response relationships in the epidemiological cancer mortality and incidence studies of this cohort.

Agreement between task-based estimates of the full-shift noise exposure and the full-shift noise dosimetry.

Noise assessments have been conducted using full-shift dosimetry and short-term task-based measurements. Advantages of the task-based method include the opportunity to directly identify high-noise exposure tasks and to target control measures, as well as obtain estimates of task-based full-shift exposures; however, there is little empirical evidence comparing the two methods. National Institute for Occupational Safety and Health assessed noise exposures at three industrial facilities using dosimetry and task-based methods with the objective of comparing the two strategies and assessing the degree of agreement and causes of disagreement. Eight indices of task-based full-shift exposures were created from task-based sampling using three methods to assess time-at-task (direct observation by industrial hygienist, end-of-shift worker estimates and supervisor estimates) and three methods to assign noise levels to tasks [direct measurement, arithmetic mean (AM) and geometric mean (GM)]. We assessed aspects of agreement (precision, bias and absolute agreement) using Bland-Altman plots and concordance correlation coefficient (CCC). Overall, the task-based methods worked fairly well, with mean biases less than +/-2.8 dBA and precision ranges of 3.3-4.4 dBA. By all measures, task-based full-shift estimates based on supervisor assessment of time-at-task agreed most poorly with the dosimetry data. The task-based full-shift estimates based on worker estimates of time-at-task generally agreed as well as those based on direct observation. For task noise level, task-based full-shift estimates based on directly measured task agreed the best with dosimetry data, while agreement for task-based indices based on task AM or GM was variable. Overall, the task-based full-shift estimates based on direct observation task and direct measured task noise level achieved the best agreement with the dosimetry data (CCC 0.84) with 95% of their differences being within 7.4 dBA and 56% of the differences <3 dBA. For this index, a high degree of accuracy was observed (accuracy coefficient = 0.96) with major cause of disagreement arising from a lack of precision (precision coefficient = 0.88). When the measurements were classified by job characteristics, significant improvements in the degree of agreement were observed in the low job mobility, low job complexity and low job variability categories. Our data suggest that a high degree of absolute agreement can be achieved between the task-based and dosimetry-based estimates of full-shift exposures. The task-based approach that uses worker reports combined with task AM or GM levels is similar to the more time-intensive direct observation method to estimate full-shift exposures.

Occupational exposure to polychlorinated biphenyls and risk of breast cancer.

BACKGROUND: Despite the endocrine system activity exhibited by polychlorinated biphenyls (PCBs), recent studies have shown little association between PCB exposure and breast cancer mortality. OBJECTIVES: To further evaluate the relation between PCB exposure and breast cancer risk, we studied incidence, a more sensitive end point than mortality, in an occupational cohort. METHODS: We followed 5,752 women employed for at least 1 year in one of three capacitor manufacturing facilities, identifying cases from questionnaires, cancer registries, and death certificates through 1998. We collected lifestyle and reproductive information via questionnaire from participants or next of kin and used semiquantitative job-exposure matrices for inhalation and dermal exposures combined. We generated standardized incidence ratios (SIRs) and standardized rate ratios and used Cox proportional hazards regression models to evaluate potential confounders and effect modifiers. RESULTS: Overall, the breast cancer SIR was 0.81 (95% confidence interval, 0.72-0.92; n = 257), and regression modeling showed little effect of employment duration or cumulative exposure. However, for the 362 women of questionnaire-identified races other than white, we observed positive, statistically significant associations with employment duration and cumulative exposure; only smoking, birth cohort, and self- or proxy questionnaire completion had statistically significant explanatory power when added to models with exposure metrics. CONCLUSIONS: We found no overall elevation in breast cancer risk after occupational exposure to PCBs. However, the exposure-related risk elevations seen among nonwhite workers, although of limited interpretability given the small number of cases, warrant further investigation, because the usual reproductive risk factors accounted for little of the increased risk.

Evaluation results of the CDC/ASPH Institute for HIV Prevention Leadership: a capacity-building educational program for HIV prevention program managers.

OBJECTIVE: The goal of this research was to evaluate changes over time in the capacity of participants of the CDC/ASPH Institute for HIV Prevention Leadership (Institute), a capacity-building program for HIV prevention program managers in minority-based, community-based organizations. Capacity was defined as the application of new skills and knowledge to participants' jobs and confidence in using those new skills and knowledge to strategically manage and apply "best practices" to their HIV prevention activities. METHODS: This is a longitudinal study involving measuring scholar capacity at three points in time: pre-Institute, post-Institute, and 6 months' post-Institute. Only responses from participants who completed all three surveys are included in this final analysis of the data (N = 94). RESULTS: Results indicate that participants from 3 years of the Institute (2002-2004) increased their capacity in HIV prevention programming and strategic planning and management. Significant changes were seen in the frequency and self-efficacy with which participants conduct several HIV prevention programming activities. Participants also reported conducting strategic planning activities at more appropriate intervals and were significantly more confident in conducting these activities. CONCLUSION: The Institute has positively and significantly increased the capacity of participants to conduct more effective HIV prevention programs on a national level.

Mortality and exposure response among 14,458 electrical capacitor manufacturing workers exposed to polychlorinated biphenyls (PCBs).

BACKGROUND: We expanded an existing cohort of workers (n = 2,588) considered highly exposed to polychlorinated biphenyls (PCBs) at two capacitor manufacturing plants to include all workers with at least 90 days of potential PCB exposure during 1939-1977 (n = 14,458). Causes of death of a priori interest included liver and rectal cancers, previously reported for the original cohort, and non-Hodgkin lymphoma (NHL), melanoma, and breast, brain, intestine, stomach, and prostate cancers, based on other studies. METHODS: We ascertained vital status of the workers through 1998, and cumulative PCB exposure was estimated using a new job exposure matrix. Analyses employed standardized mortality ratios (SMRs; U.S., state, and county referents) and Poisson regression modeling. RESULTS: Mortality from NHL, melanoma, and rectal, breast, and brain cancers were neither in excess nor associated with cumulative exposure. Mortality was not elevated for liver cancer [21 deaths; SMR 0.89; 95% confidence interval (CI), 0.55-1.36], but increased with cumulative exposure (trend p-value = 0.071). Among men, stomach cancer mortality was elevated (24 deaths; SMR 1.53; 95% CI, 0.98-2.28) and increased with cumulative exposure (trend p-value = 0.039). Among women, intestinal cancer mortality was elevated (67 deaths; SMR 1.31; 95% CI, 1.02-1.66), especially in higher cumulative exposure categories, but without a clear trend. Prostate cancer mortality, which was not elevated (34 deaths; SMR 1.04; 95% CI, 0.72-1.45), increased with cumulative exposure (trend p-value = 0.0001). CONCLUSIONS: This study corroborates previous studies showing increased liver cancer mortality, but we cannot clearly associate rectal, stomach, and intestinal cancers with PCB exposure. This is the first PCB cohort showing a strong exposure-response relationship for prostate cancer mortality.

Development of a curriculum to enhance community-based organizations' capacity for effective HIV prevention programming and management.

Community-based organizations (CBOs), particularly minority-based CBOs, are instrumental in the delivery of HIV/AIDS prevention programs and services. Despite a tremendous need, many CBOs lack the capacity to plan, implement, and evaluate targeted prevention interventions to serve culturally diverse populations. This article describes a comprehensive, innovative curriculum for building capacity within CBOs providing HIV prevention programming. An overview of the process through which the Centers for Disease Control and Prevention/Association of Schools of Public Health Institute for HIV Prevention Leadership evolved is discussed. The development of the curriculum occurred in four phases: needs assessment, curricular design, implementation, and evaluation. A description of the Institute's evaluation strategies and procedures are described. Selected preliminary evaluation results from two cohorts of participants indicate significant knowledge gains and high levels of satisfaction with the Institute sessions, assignments, and faculty. The Institute's model shows promise for the provision of capacity building education at the individual and organizational level for community-based professionals implementing HIV prevention programs.

Update: cohort mortality study of workers highly exposed to polychlorinated biphenyls (PCBs) during the manufacture of electrical capacitors, 1940-1998.

BACKGROUND: The National Institute for Occupational Safety and Health previously reported mortality for a cohort of workers considered highly exposed to polychlorinated biphenyls (PCBs) between 1939 and 1977 at two electrical capacitor manufacturing plants. The current study updated vital status, examined liver and rectal cancer mortality previously reported in excess in this cohort and evaluated mortality from non-Hodgkin's lymphoma (NHL) and cancers of the stomach, intestine, breast, prostate, skin (melanoma) and brain reported to be in excess in other cohort and case-control studies of PCB-exposed persons. METHODS: Mortality was updated through 1998 for 2572 workers. Age-, gender-, race- and calendar year-adjusted standardized mortality ratios (SMRs) and 95% confidence intervals (CI) were calculated using U.S., state and county referent rates. SMRs using U.S. referent rates are reported. Duration of employment was used as a surrogate for exposure. RESULTS: Consistent with the previous follow-up, mortality from biliary passage, liver and gall bladder cancer was significantly elevated (11 deaths, SMR 2.11, CI 1.05 - 3.77), but mortality from rectal cancer was not (6 deaths, SMR 1.47, CI 0.54 - 3.21). Among women, mortality from intestinal cancer (24 deaths, SMR 1.89, CI 1.21 - 2.82) and from "other diseases of the nervous system and sense organs", which include Parkinson's disease and amyotrophic lateral sclerosis, (15 deaths, SMR 2.07, CI 1.16 - 3.42) were elevated. There were four ALS deaths, all women (SMR 4.35, CI 1.19-11.14). Mortality was elevated for myeloma (7 deaths, SMR 2.11, CI 0.84 - 4.34), particularly among workers employed 10 years or more (5 deaths, SMR 2.80, CI 0.91 - 6.54). No linear associations between mortality and duration of employment were observed for the cancers of interest. CONCLUSION: This update found that the earlier reported excess in this cohort for biliary, liver and gall bladder cancer persisted with longer follow-up. Excess mortality for intestinal cancer among women was elevated across categories of duration of employment; myeloma mortality was highest among those working 10 years or more. The small numbers of deaths from liver and intestinal cancers, myeloma and nervous system diseases coupled with the lack of an exposure-response relationship with duration of employment preclude drawing definitive conclusions regarding PCB exposure and these causes of death.

Mortality among workers exposed to polychlorinated biphenyls (PCBs) in an electrical capacitor manufacturing plant in Indiana: an update.

An Indiana capacitor-manufacturing cohort (n=3,569) was exposed to polychlorinated biphenyls (PCBs) from 1957 to 1977. The original study of mortality through 1984 found excess melanoma and brain cancer; other studies of PCB-exposed individuals have found excess non-Hodgkin lymphoma and rectal, liver, biliary tract, and gallbladder cancer. Mortality was updated through 1998. Analyses have included standardized mortality ratios (SMRs) and 95% confidence intervals (CIs) using rates for Indiana and the United States, standardized rate ratios (SRRs), and Poisson regression rate ratios (RRs). Estimated cumulative exposure calculations used a new job-exposure matrix. Mortality overall was reduced (547 deaths; SMR, 0.81; 95% CI, 0.7-0.9). Non-Hodgkin lymphoma mortality was elevated (9 deaths; SMR, 1.23; 95% CI, 0.6-2.3). Melanoma remained in excess (9 deaths; SMR, 2.43; 95% CI, 1.1-4.6), especially in the lowest tertile of estimated cumulative exposure (5 deaths; SMR, 3.72; 95% CI, 1.2-8.7). Seven of the 12 brain cancer deaths (SMR, 1.91; 95% CI, 1.0-3.3) occurred after the original study. Brain cancer mortality increased with exposure (in the highest tertile, 5 deaths; SMR, 2.71; 95% CI, 0.9-6.3); the SRR dose-response trend was significant (p=0.016). Among those working >or= 90 days, both melanoma (8 deaths; SMR, 2.66; 95% CI, 1.1-5.2) and brain cancer (11 deaths; SMR, 2.12; 95% CI, 1.1-3.8) were elevated, especially for women: melanoma, 3 deaths (SMR, 5.99; 95% CI, 1.2-17.5); brain cancer, 3 deaths (SMR, 2.87; 95% CI, 0.6-8.4). These findings of excess melanoma and brain cancer mortality confirm results of the original study. Melanoma mortality was not associated with estimated cumulative exposure. Brain cancer mortality did not demonstrate a clear dose-response relationship with estimated cumulative exposure.

Polychlorinated biphenyls and neurodegenerative disease mortality in an occupational cohort.

BACKGROUND: Production of polychlorinated biphenyls (PCBs) ended in the United States in the 1970s, but PCBs persist in the environment and are detectable in the blood of approximately 80% of Americans over age 50. PCBs decrease dopamine levels in rats and monkeys. Loss of dopamine is the hallmark of Parkinson disease, a neurodegenerative disease. There are no epidemiologic studies of PCBs and neurodegenerative disease. METHODS: We conducted a retrospective mortality study of 17,321 PCB-exposed workers to determine whether mortality from Parkinson disease, dementia, and amyotrophic lateral sclerosis was elevated compared with the U.S. population. All workers had a least 90 days employment in 1 of 3 electrical capacitor plants using PCBs from the 1940s to the 1970s. PCB serum levels from a sample of these workers in the 1970s were approximately 10 times the level of community controls. RESULTS: We found no overall excess of Parkinson disease, amyotrophic lateral sclerosis, or dementia in the PCB-exposed cohort (standardized mortality ratios [SMRs]-1.40, 1.11, and 1.26, respectively, and number of deaths-14, 10, and 28 respectively). However, sex-specific analyses revealed that women had an excess of amyotrophic lateral sclerosis (SMR-2.26; 95% confidence interval [CI] = 1.08-4.15; 10 deaths). Furthermore, among highly exposed women (defined by a job-exposure matrix), we found an excess of Parkinson disease (SMR-2.95; 95% CI = 1.08-6.42; 6 deaths) and dementia (SMR-2.04; 95% CI = 1.12-3.43; 14 deaths). CONCLUSIONS: Our data are limited due to small numbers and reliance on mortality rather than incidence data, but are suggestive of an effect of PCBs on neurodegenerative disease for women. The literature does not offer an explanation for why women would be more affected than men by PCB exposure for these outcomes.

Microbicide acceptability among high-risk urban U.S. women: experiences and perceptions of sexually transmitted HIV prevention.

OBJECTIVES: The objectives of this study were to measure microbicide acceptability among high-risk women in Hartford, Connecticut, and contextual factors likely to affect acceptability and use. GOAL: The goal of this study was to assess usefulness of microbicides for HIV/sexually transmitted infection (STI) prevention for high-risk women. STUDY: Ethnographic interviews (n = 75) and a survey (n = 471) explored women's perspectives on HIV/STI prevention, vaginal contraceptives similar to microbicides, and microbicide acceptability. Participants (n = 94) in a 2-week behavioral trial used an over-the-counter vaginal moisturizer to simulate microbicide use during sex with primary, casual, and/or paying partners. RESULTS: Findings showed limited experience with vaginal contraceptives, but high interest in microbicides as an alternative to condoms, indicated by an acceptability index score of 2.73 (standard deviation, 0.49; scale of 1-4) in the overall sample. General microbicide acceptability varied by ethnicity, prior contraceptive and violence/abuse experiences, relationship power, and other attitudinal factors. The simulation trial indicated significant willingness to use the product in various locations and with all types of partners. CONCLUSIONS: Vaginal microbicides may improve prevention outcomes for high-risk inner-city women.

The contribution of focus groups in the evaluation of hearing conservation program (HCP) effectiveness.

PROBLEM: Exclusive reliance on such practices as policy review, audiometric testing audits, and noise surveillance to evaluate the effectiveness of workplace hearing conservation programs (HCP) fails to capture the impact of these programs as experienced by workers at the "shop floor" and offers little insight into the reasons and potential remedies for noted deficiencies. METHODS: A qualitative approach for evaluating industrial HCPs (and their various components) is discussed using three industrial populations as case studies. For each study population, this paper illustrates how focus groups, comprised of line workers and supervisors, were used to clarify and augment information gathered through more traditional program assessments to provide a more enriched picture of hearing conservation practices. Descriptive data on plant hearing conservation program practices at each plant are presented with a comparison of proactive elements of each program relative to the Occupational Safety and Health Administration (OSHA) Hearing Conservation Amendment (HCA) requirement and to internal plant policy. RESULTS: Yearly program evaluation with input from all end-users is important in the process of hearing loss prevention. The qualitative assessment outlined in this paper serves as a basis for future quantitative assessments of HCP effectiveness using hearing threshold data and noise exposure assessments to examine changes in hearing levels as a function of noise exposure and other risk factors for hearing loss.

Evaluation of the risk of noise-induced hearing loss among unscreened male industrial workers.

Variability in background risk and distribution of various risk factors for hearing loss may explain some of the diversity in excess risk of noise-induced hearing loss (NIHL). This paper examines the impact of various risk factors on excess risk estimates of NIHL using data from the 1968-1972 NIOSH Occupational Noise and Hearing Survey (ONHS). Previous analyses of a subset of these data focused on 1172 highly "screened" workers. In the current analysis, an additional 894 white males (609 noise-exposed and 285 controls), who were excluded for various reasons (i.e., nonoccupational noise exposure, otologic or medical conditions affecting hearing, prior occupational noise exposure) have been added 2066) to assess excess risk of noise-induced material impairment in an unscreened population. Data are analyzed by age, duration of exposure, and sound level (8-h TWA) for four different definitions of noise-induced hearing impairment, defined as the binaural pure-tone average (PTA) hearing threshold level greater than 25 dB for the following frequencies: (a) 1-4 kHz (PTA1234), (b) 1-3 kHz (PTA123), (c) 0.5, 1, and 2 kHz (PTA512), and (d) 3, 4, and 6 kHz (PTA346). Results indicate that populations with higher background risks of hearing loss may show lower excess risks attributable to noise relative to highly screened populations. Estimates of lifetime excess risk of hearing impairment were found to be significantly different between screened and unscreened population for noise levels greater than 90 dBA. Predicted age-related risk of material hearing impairment in the ONHS unscreened population was similar to that predicted from Annex B and C of ANSI S3.44 for ages less than 60 years. Results underscore the importance of understanding differential risk patterns for hearing loss and the use of appropriate reference (control) populations when evaluating risk of noise-induced hearing impairment among contemporary industrial populations.

Evaluation of a safety training program in three food service companies.

PROBLEM: Outcome measures for safety training effectiveness research often do not include measures such as occupational injury experience. Effectiveness mediators also receive sparse attention. METHOD: A new safety training curriculum was delivered to workers in a stratified random sample of food service facilities across three companies. A similar group of facilities received usual training. We collected post-test measures of demographic variables, safety knowledge, perceptions of transfer of training climate, and workers' compensation claim data for one year after the initial training activities. RESULTS: Knowledge test scores were apparently higher in the new-training units than in the usual-training units. Some demographic variables were inconsistently associated with these differences. Evidence for reduction of the injury rate associated with the new training was observed from two companies but only approached significance for one company. A second company revealed a similar but non-significant trend. Knowledge scores were not significantly associated with lower injury rates. DISCUSSION: We found evidence that safety training increases knowledge and reduces injuries. We found almost no evidence of effects of training effectiveness mediators, including no relationship between safety knowledge and injury experience. Methodological issues related to conducting a large study may have influenced these results. IMPACT ON INDUSTRY: Although safety training leads to greater knowledge and, in some cases, reduced occupational injuries, the influence of mediating variables remains to be fully explained.

Distribution of risk factors for hearing loss: implications for evaluating risk of occupational noise-induced hearing loss.

This paper presents an analysis of hearing threshold levels among 2066 white male workers employed in various U.S. industries studied in the 1968-72 NIOSH Occupational Noise and Hearing Survey (ONHS). The distribution of hearing threshold levels (HTL) is examined in relation to various risk factors (age, prior occupational noise, medical conditions) for hearing loss among a population of noise exposed and control (low noise-exposed) industrial workers. Previous analyses of a subset of these data from the ONHS focused on 1172 highly "screened" workers. An additional 894 male workers (609 noise-exposed and 285 controls), who were excluded for various reasons (i.e., nonoccupational noise exposure, otologic or medical conditions affecting hearing, prior occupational noise exposure) have been added to examine hearing loss in an unscreened population. Data are analyzed by age, duration of exposure, and sound level (8-h TWA) by individual test frequency. Results indicate that hearing threshold levels are higher among unscreened noise-exposed and control workers relative to screened workers. Analysis of risk factors such as nonoccupational noise exposure, medical conditions, and type of industry among unscreened controls indicated that these factors were not significantly associated with increased mean HTLs or risk of material impairment over and above what is expected due to age. Age-specific mean hearing threshold levels (and percentiles of the distribution) among the unscreened ONHS control population may be used as a comparison population of low-noise exposed white male industrial workers for evaluating the effectiveness of hearing conservation programs for workers less than 55 years of age. To make valid inferences regarding occupational noise-induced hearing loss, it is important to use hearing data from reference (control) populations that are similar with respect to the degree of subject screening, type of work force (blue vs white collar), and the distribution of other risk factors for hearing loss.