Occupational Exposure to Knee Loading and the Risk of Osteoarthritis of the Knee: A Systematic Review and a Dose-Response Meta-Analysis.

BACKGROUND: Osteoarthritis of the knee is considered to be related to knee straining activities at work. The objective of this review is to assess the exposure dose-response relation between kneeling or squatting, lifting, and climbing stairs at work, and knee osteoarthritis. METHODS: We included cohort and case-control studies. For each study that reported enough data, we calculated the odds ratio (OR) per 5,000 hours of cumulative kneeling and per 100,000 kg of cumulative lifting. We pooled these incremental ORs in a random effects meta-analysis. RESULTS: We included 15 studies (2 cohort and 13 case-control studies) of which nine assessed risks in more than two exposure categories. We considered all but one study at high risk of bias. The incremental OR per 5,000 hours of kneeling was 1.26 (95% confidence interval 1.17-1.35, 5 studies, moderate quality evidence) for a log-linear exposure dose-response model. For lifting, there was no exposure dose-response per 100,000 kg of lifetime lifting (OR 1.00, 95% confidence interval 1.00-1.01). For climbing, an exposure dose-response could not be calculated. CONCLUSION: There is moderate quality evidence that longer cumulative exposure to kneeling or squatting at work leads to a higher risk of osteoarthritis of the knee. For other exposure, there was no exposure dose-response or there were insufficient data to establish this. More reliable exposure measurements would increase the quality of the evidence.

Inclusion criteria for outcomes of studies not clearly reported in Cochrane systematic reviews.

OBJECTIVES: The objective of this study was to survey how outcomes in recent Cochrane reviews were defined and used for inclusion of studies and how this compares with guidance on preventing outcome reporting bias. STUDY DESIGN AND SETTING: A survey of Cochrane reviews. We extracted data on the outcomes and how the outcomes were used for inclusion of studies in the review. RESULTS: We included 52 reviews with a mean of 8.4 (standard deviation, 4.3) outcomes. Of all reviews, 47 (90%) used primary and secondary outcomes as the names for their review's outcomes but without further definition. None reported using a core outcome set. Forty reviews (77%) did not explain if they used outcomes for inclusion of studies, 8 (15%) stated that studies were included if they reported either primary or secondary outcomes, 1 (2%) reported that outcomes were not used for inclusion, and for 3 (6%), this was unclear. CONCLUSION: In a sample of Cochrane reviews, most reviews did not state if outcomes were used for inclusion of studies. Better explanation of inclusion decisions is needed to be able to understand the risk of outcome reporting bias in a review. Consistent guidance in names and definitions for different types of outcomes used in systematic reviews is needed.

Personal protective equipment for preventing highly infectious diseases due to exposure to contaminated body fluids in healthcare staff.

BACKGROUND: In epidemics of highly infectious diseases, such as Ebola Virus Disease (EVD) or SARS, healthcare workers (HCW) are at much greater risk of infection than the general population, due to their contact with patients' contaminated body fluids. Contact precautions by means of personal protective equipment (PPE) can reduce the risk. It is unclear which type of PPE protects best, what is the best way to remove PPE, and how to make sure HCWs use PPE as instructed. OBJECTIVES: To evaluate which type or component of full-body PPE and which method of donning or removing (doffing) PPE have the least risk of self-contamination or infection for HCWs, and which training methods most increase compliance with PPE protocols. SEARCH METHODS: We searched MEDLINE (PubMed up to 8 January 2016), Cochrane Central Register of Trials (CENTRAL up to 20 January 2016), EMBASE (embase.com up to 8 January 2016), CINAHL (EBSCOhost up to 20 January 2016), and OSH-Update up to 8 January 2016. We also screened reference lists of included trials and relevant reviews, and contacted NGOs and manufacturers of PPE. SELECTION CRITERIA: We included all eligible controlled studies that compared the effect of types or components of PPE in HCWs exposed to highly infectious diseases with serious consequences, such as EVD and SARS, on the risk of infection, contamination, or noncompliance with protocols. This included studies that simulated contamination with fluorescent markers or a non-pathogenic virus.We also included studies that compared the effect of various ways of donning or removing PPE, and the effects of various types of training in PPE use on the same outcomes. DATA COLLECTION AND ANALYSIS: Two authors independently selected studies, extracted data and assessed risk of bias in included trials. We intended to perform meta-analyses but we did not find sufficiently similar studies to combine their results. MAIN RESULTS: We included nine studies with 1200 participants evaluating ten interventions. Of these, eight trials simulated the exposure with a fluorescent marker or virus or bacteria containing fluids. Five studies evaluated different types of PPE against each other but two did not report sufficient data. Another two studies compared different types of donning and doffing and three studies evaluated the effect of different types of training.None of the included studies reported a standardised classification of the protective properties against viral penetration of the PPE, and only one reported the brand of PPE used. None of the studies were conducted with HCWs exposed to EVD but in one study participants were exposed to SARS. Different types of PPE versus each otherIn simulation studies, contamination rates varied from 25% to 100% of participants for all types of PPE. In one study, PPE made of more breathable material did not lead to a statistically significantly different number of spots with contamination but did have greater user satisfaction (Mean Difference (MD) -0.46 (95% Confidence Interval (CI) -0.84 to -0.08, range 1 to 5, very low quality evidence). In another study, gowns protected better than aprons. In yet another study, the use of a powered air-purifying respirator protected better than a now outdated form of PPE. There were no studies on goggles versus face shields, on long- versus short-sleeved gloves, or on the use of taping PPE parts together. Different methods of donning and doffing procedures versus each otherTwo cross-over simulation studies (one RCT, one CCT) compared different methods for donning and doffing against each other. Double gloving led to less contamination compared to single gloving (Relative Risk (RR) 0.36; 95% CI 0.16 to 0.78, very low quality evidence) in one simulation study, but not to more noncompliance with guidance (RR 1.08; 95% CI 0.70 to 1.67, very low quality evidence). Following CDC recommendations for doffing led to less contamination in another study (very low quality evidence). There were no studies on the use of disinfectants while doffing. Different types of training versus each otherIn one study, the use of additional computer simulation led to less errors in doffing (MD -1.2, 95% CI -1.6 to -0.7) and in another study additional spoken instruction led to less errors (MD -0.9, 95% CI -1.4 to -0.4). One retrospective cohort study assessed the effect of active training - defined as face-to-face instruction - versus passive training - defined as folders or videos - on noncompliance with PPE use and on noncompliance with doffing guidance. Active training did not considerably reduce noncompliance in PPE use (Odds Ratio (OR) 0.63; 95% CI 0.31 to 1.30) but reduced noncompliance with doffing procedures (OR 0.45; 95% CI 0.21 to 0.98, very low quality evidence). There were no studies on how to retain the results of training in the long term or on resource use.The quality of the evidence was very low for all comparisons because of high risk of bias in studies, indirectness of evidence, and small numbers of participants. This means that it is likely that the true effect can be substantially different from the one reported here. AUTHORS' CONCLUSIONS: We found very low quality evidence that more breathable types of PPE may not lead to more contamination, but may have greater user satisfaction. We also found very low quality evidence that double gloving and CDC doffing guidance appear to decrease the risk of contamination and that more active training in PPE use may reduce PPE and doffing errors more than passive training. However, the data all come from single studies with high risk of bias and we are uncertain about the estimates of effects.We need simulation studies conducted with several dozens of participants, preferably using a non-pathogenic virus, to find out which type and combination of PPE protects best, and what is the best way to remove PPE. We also need randomised controlled studies of the effects of one type of training versus another to find out which training works best in the long term. HCWs exposed to highly infectious diseases should have their use of PPE registered and should be prospectively followed for their risk of infection.

Inclusion of nonrandomized studies in Cochrane systematic reviews was found to be in need of improvement.

OBJECTIVES: Nonrandomized studies (NRSs) are considered to provide less reliable evidence for intervention effects. However, these are included in Cochrane reviews, despite discouragement. There has been no evaluation of when and how these designs are used. Therefore, we conducted an overview of current practice. STUDY DESIGN AND SETTING: We included all Cochrane reviews that considered NRS, conducting inclusions and data extraction in duplicate. RESULTS: Of the included 202 reviews, 114 (56%) did not cite a reason for including NRS. The reasons were divided into two major categories: NRS were included because randomized controlled trials (RCTs) are wanted (N = 81, 92%) but not feasible, lacking, or insufficient alone or because RCTs are not needed (N = 7, 8%). A range of designs were included with controlled before-after studies as the most common. Most interventions were nonpharmaceutical and the settings nonmedical. For risk of bias assessment, Cochrane Effective Practice and Organisation of Care Group's checklists were used by most reviewers (38%), whereas others used a variety of checklists and self-constructed tools. CONCLUSION: Most Cochrane reviews do not justify including NRS. When they do, most are not in line with Cochrane recommendations. Risk of bias assessment varies across reviews and needs improvement.

Gloves, extra gloves or special types of gloves for preventing percutaneous exposure injuries in healthcare personnel.

BACKGROUND: Healthcare workers are at risk of acquiring viral diseases such as hepatitis B, hepatitis C and HIV through exposure to contaminated blood and body fluids at work. Most often infection occurs when a healthcare worker inadvertently punctures the skin of their hand with a sharp implement that has been used in the treatment of an infected patient, thus bringing the patient's blood into contact with their own. Such occurrences are commonly known as percutaneous exposure incidents. OBJECTIVES: To determine the benefits and harms of extra gloves for preventing percutaneous exposure incidents among healthcare workers versus no intervention or alternative interventions. SEARCH METHODS: We searched CENTRAL, MEDLINE, EMBASE, NHSEED, Science Citation Index Expanded, CINAHL, NIOSHTIC, CISDOC, PsycINFO and LILACS until 26 June 2013. SELECTION CRITERIA: Randomised controlled trials (RCTs) with healthcare workers as the majority of participants, extra gloves or special types of gloves as the intervention, and exposure to blood or bodily fluids as the outcome. DATA COLLECTION AND ANALYSIS: Two authors independently assessed study eligibility and risk of bias, and extracted data. We performed meta-analyses for seven different comparisons. MAIN RESULTS: We found 34 RCTs that included 6890 person-operations as participating units and reported on 46 intervention-control group comparisons. We grouped interventions as follows: increased layers of standard gloves, gloves manufactured with special protective materials or thicker gloves, and gloves with puncture indicator systems. Indicator gloves show a coloured spot when they are perforated. Participants were surgeons in all studies and they used at least one pair of standard gloves as the control intervention. Twenty-seven studies also included other surgical staff (e.g. nurses). All but one study used perforations in gloves as an indication of exposure. The median control group rate was 18.5 perforations per 100 person-operations. Seven studies reported blood stains on the skin and two studies reported self reported needlestick injuries. Six studies reported dexterity as visual analogue scale scores for the comparison double versus single gloves, 13 studies reported outer glove perforations. We judged the included studies to have a moderate to high risk of bias.We found moderate-quality evidence that double gloves compared to single gloves reduce the risk of glove perforation (rate ratio (RR) 0.29, 95% confidence interval (CI) 0.23 to 0.37) and the risk of blood stains on the skin (RR 0.35, 95% CI 0.17 to 0.70). Two studies with a high risk of bias also reported the effect of double compared to single gloves on needlestick injuries (RR 0.58, 95% CI 0.21 to 1.62).We found low-quality evidence in one small study that the use of three gloves compared to two gloves reduces the risk of perforation further (RR 0.03, 95% CI 0.00 to 0.52). There was similar low-quality evidence that the use of one fabric glove over one normal glove reduces perforations compared to two normal gloves (RR 0.24, 95% CI 0.06 to 0.93). There was moderate-quality evidence that this effect was similar for the use of one special material glove between two normal material gloves. Thicker gloves did not perform better than thinner gloves.There was moderate to low-quality evidence in two studies that an indicator system does not reduce the total number of perforations during an operation even though it reduces the number of perforations per glove used.There was moderate-quality evidence that double gloves have a similar number of outer glove perforations as single gloves, indicating that there is no loss of dexterity with double gloves (RR 1.10, 95% CI 0.93 to 1.31). AUTHORS' CONCLUSIONS: There is moderate-quality evidence that double gloving compared to single gloving during surgery reduces perforations and blood stains on the skin, indicating a decrease in percutaneous exposure incidents. There is low-quality evidence that triple gloving and the use of special gloves can further reduce the risk of glove perforations compared to double gloving with normal material gloves. The preventive effect of double gloves on percutaneous exposure incidents in surgery does not need further research. Further studies are needed to evaluate the effectiveness and cost-effectiveness of special material gloves and triple gloves, and of gloves in other occupational groups.

Interventions to prevent occupational noise-induced hearing loss: a Cochrane systematic review.

OBJECTIVE: To assess the effectiveness of interventions for preventing occupational noise exposure or hearing loss compared to no intervention or alternative interventions. DESIGN: We searched biomedical databases up to 25 January 2012 for randomized controlled trials (RCT), controlled before-after studies and interrupted time-series of hearing loss prevention among workers exposed to noise. STUDY SAMPLE: We included 19 studies with 82 794 participants evaluating effects of hearing loss prevention programs (HLPP). The overall quality of studies was low to very low, as rated using the GRADE approach. RESULTS: One study of stricter legislation showed a favorable effect on noise levels. Three studies, of which two RCTs, did not find an effect of a HLPP. Four studies showed that better use of hearing protection devices in HLPPs decreased the risk of hearing loss. In four other studies, workers in a HLPP still had a 0.5 dB greater hearing loss at 4 kHz (95% CI - 0.5 to 1.7) than non-exposed workers. In two similar studies there was a substantial risk of hearing loss in spite of a HLPP. CONCLUSIONS: Stricter enforcement of legislation and better implementation of HLPPs can reduce noise levels in workplaces. Better evaluations of technical interventions and long-term effects are needed.

Occupational safety and health enforcement tools for preventing occupational diseases and injuries.

BACKGROUND: There is uncertainty as to whether and what extent occupational safety and health regulation and legislation enforcement activities, such as inspections, are effective and efficient to improve workers' health and safety. We use the term regulation to refer both to regulation and legislation. OBJECTIVES: To assess the effects of occupational safety and health regulation enforcement tools for preventing occupational diseases and injuries. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (PubMed), EMBASE (embase.com), CINAHL (EBSCO), PsycINFO (Ovid), OSH update, HeinOnline, Westlaw International, EconLit and Scopus from the inception of each database until January 2013. We also checked reference lists of included articles and contacted study authors to identify additional published, unpublished and ongoing studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs), controlled before-after studies (CBAs), interrupted time series (ITS) and econometric panel studies of firms or workplaces evaluating inspections, warnings or orders, citations or fines, prosecution or firm closure by governmental representatives and if the outcomes were injuries, diseases or exposures.In addition, we included qualitative studies of workers' or employers' attitudes or beliefs towards enforcement tools. DATA COLLECTION AND ANALYSIS: Pairs of authors independently extracted data on the main characteristics, the risk of bias and the effects of the interventions. We expressed intervention effects as risk ratios (RR) or mean differences (MD). We recalculated other effect measures into RRs or MDs. We combined the results of similar studies in a meta-analysis. MAIN RESULTS: We located 23 studies: two RCTs with 1414 workplaces, two CBAs with 9903 workplaces, one ITS with six outcome measurements, 12 panel studies and six qualitative studies with 310 participants. Studies evaluated the effects of inspections in general and the effects of their consequences, such as penalties. Studies on the effects of prosecution, warnings or closure were not available or were of such quality that we could not include their results. The effect was measured on injury rates, on exposure to physical workload and on compliance with regulation, with a follow-up varying from one to four years. All studies had serious limitations and therefore the quality of the evidence was low to very low. The injury rates in the control groups varied across studies from 1 to 23 injuries per 100 person-years and compliance rates varied from 40% to 75% being compliant.The effects of inspections were inconsistent in seven studies: injury rates decreased or stayed at a similar level compared to no intervention at short and medium-term follow-up. In studies that found a decrease the effect was small with a 10% decrease of the injury rate. At long-term follow-up, in one study there was a significant decrease of 23% (95% confidence interval 8% to 23%) in injury rates and in another study a substantial decrease in accident rates, both compared to no intervention.First inspections, follow-up inspections, complaint and accident inspections resulted in higher compliance rates compared to the average effect of any other type of inspections.In small firms, inspections with citations or with more penalties could result in fewer injuries or more compliance in the short term but not in the medium term.Longer inspections and more frequent inspections probably do not result in more compliance.In two studies, there was no adverse effect of inspections on firm survival, employment or sales.Qualitative studies show that there is support for enforcement among workers. However, workers doubt if the inspections are effective because inspections are rare and violations can be temporarily fixed to mislead inspectors. AUTHORS' CONCLUSIONS: There is evidence that inspections decrease injuries in the long term but not in the short term. The magnitude of the effect is uncertain. There are no studies that used chemical or physical exposures as outcome. Specific, focused inspections could have larger effects than inspections in general. The effect of fines and penalties is uncertain. The quality of the evidence is low to very low and therefore these conclusions are tentative and can be easily changed by better future studies. There is an urgent need for better designed evaluations, such as pragmatic randomised trials, to establish the effects of existing and novel enforcement methods, especially on exposure and disorders.

Interventions to prevent occupational noise-induced hearing loss.

BACKGROUND: Millions of workers worldwide are exposed to noise levels that increase their risk of hearing impairment. Little is known about the effectiveness of hearing loss prevention interventions. OBJECTIVES: To assess the effectiveness of non-pharmaceutical interventions for preventing occupational noise exposure or occupational hearing loss compared to no intervention or alternative interventions. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; and OSH update to 25 January 2012. SELECTION CRITERIA: We included randomised controlled trials (RCT), controlled before-after studies (CBA) and interrupted time-series (ITS) of non-clinical hearing loss prevention interventions under field conditions among workers exposed to noise. DATA COLLECTION AND ANALYSIS: Two authors independently assessed study eligibility and risk of bias and extracted data. MAIN RESULTS: We included 25 studies. We found no controlled studies on engineering controls for noise exposure but one study evaluated legislation to reduce noise exposure in a 12-year time-series analysis. Eight studies with 3,430 participants evaluated immediate and long-term effects of personal hearing protection devices (HPDs) and sixteen studies with 82,794 participants evaluated short and long-term effects of hearing loss prevention programmes (HLPPs). The overall quality of studies was low to very low.The one ITS study that evaluated the effect of new legislation in reducing noise exposure found that the median noise level decreased by 27.7 dB(A) (95% confidence interval (CI) -36.1 to -19.3 dB) immediately after the implementation of stricter legislation and that this was associated with a favourable downward trend in time of -2.1 dB per year (95% CI -4.9 to 0.7).Hearing protection devices attenuated noise with about 20 dB(A) with variation among brands and types but for ear plugs these findings depended almost completely on proper instruction of insertion. Noise attenuation ratings of hearing protection under field conditions were consistently lower than the ratings provided by the manufacturers.One cluster-RCT compared a three-year information campaign as part of a hearing loss prevention programme for agricultural students to audiometry only with three and 16-year follow-up but there were no significant differences in hearing loss. Another study compared a HLPP, which provided regular personal noise exposure information, to a programme without this information in a CBA design. Exposure information was associated with a favourable but non-significant reduction of the rate of hearing loss of -0.82 dB per year (95% CI -1.86 to 0.22). Another cluster-RCT evaluated the effect of extensive on-site training sessions and the use of personal noise-level indicators versus information only on noise levels but did not find a significant difference after four months follow-up (Mean Difference (MD) -0.30 dB(A) (95%CI -3.95 to 3.35).There was very low quality evidence in four very long-term studies, that better use of HPDs as part of a HLPP decreased the risk of hearing loss compared to less well used hearing protection in HLPPs. Other aspects of the HLPP such as training and education of workers or engineering controls did not show a similar effect.In four long-term studies, workers in a HLPP still had a 0.5 dB greater hearing loss at 4 kHz than workers that were not exposed to noise (95% CI -0.5 to 1.7) which is about the level of hearing loss caused by exposure to 85 dB(A). In addition, two other studies showed substantial risk of hearing loss in spite of the protection of a HLPP compared to non-exposed workers. AUTHORS' CONCLUSIONS: There is low quality evidence that implementation of stricter legislation can reduce noise levels in workplaces. Even though case studies show that substantial reductions in noise levels in the workplace can be achieved, there are no controlled studies of the effectiveness of such measures. The effectiveness of hearing protection devices depends on training and their proper use. There is very low quality evidence that the better use of hearing protection devices as part of HLPPs reduces the risk of hearing loss, whereas for other programme components of HLPPs we did not find such an effect. Better implementation and reinforcement of HLPPs is needed. Better evaluations of technical interventions and long-term effects are needed.