Common Causes Associated With Occupational Injuries in Iranian Health Care Workers : A Systematic Review and Meta-Analysis Study

Occupational injuries are the most important hazards threatening health care workers (HCWs). Among occupational injuries, needle stick injuries (NSIs) are one of the most common injuries to HCWs during work.1 HCWs are vulnerable to contact with patients.2 NSIs in HCWs significantly increase the risk of transmission of infectious diseases such as AIDS and hepatitis B and C.3-5 According to the World Health Organization (WHO), there have been 16 000 cases of hepatitis C, 66 000 cases of hepatitis B, and 1000 AIDS cases following occupational exposure.6 In addition to the transmission of infectious diseases, these injuries can endanger the mental health of HCWs and impose heavy costs resulting from the treatment of infected personnel.5,7 In addition to the risk of illness and death, psychological damage, and long-term disability, occupational exposure to sharp objects is also associated with fear, tension, and anxiety.8,9 Furthermore, it imposes a heavy economic burden on countries.10 A serious infection with blood-borne viruses can cost $1 million because of tests, follow-up, disability, and loss of work; the cost of preventing occupational injuries is estimated to be $3000.10,11 Despite the high prevalence of this occupational injuries among HCWs, they can be prevented.12-14 Identifying the factors associated with occupational injuries helps health policy-makers minimize and prevent these types of injuries. There are no coherent reports on the common causes of occupational injuries among Iran’s HCWs; thus, this meta-analysis aimed to determine precisely the common causes of occupational injuries in Iranian HCWs.


Introduction
Occupational injuries are the most important hazards threatening health care workers (HCWs).Among occupational injuries, needle stick injuries (NSIs) are one of the most common injuries to HCWs during work. 1 HCWs are vulnerable to contact with patients. 2NSIs in HCWs significantly increase the risk of transmission of infectious diseases such as AIDS and hepatitis B and C. [3][4][5] According to the World Health Organization (WHO), there have been 16 000 cases of hepatitis C, 66 000 cases of hepatitis B, and 1000 AIDS cases following occupational exposure. 6In addition to the transmission of infectious diseases, these injuries can endanger the mental health of HCWs and impose heavy costs resulting from the treatment of infected personnel. 5,7n addition to the risk of illness and death, psychological damage, and long-term disability, occupational exposure to sharp objects is also associated with fear, tension, and anxiety. 8,9Furthermore, it imposes a heavy economic burden on countries. 10A serious infection with blood-borne viruses can cost $1 million because of tests, follow-up, disability, and loss of work; the cost of preventing occupational injuries is estimated to be $3000. 10,11][14] Identifying the factors associated with occupational injuries helps health policy-makers minimize and prevent these types of injuries.There are no coherent reports on the common causes of occupational injuries among Iran's HCWs; thus, this meta-analysis aimed to determine precisely the common causes of occupational injuries in Iranian HCWs.
The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (Figure 1) were used to conduct and report the results of this study.

Search Strategy and Eligibility Criteria
The main questions of the researcher in this meta-analysis were, "What are the most common causes of occupational injuries in Iranian HCWs?" and "What is the prevalence rate of common causes of occupational injuries in Iranian HCWs?"To answer these questions, articles on occupational injuries in Iranian HCWs that had been published in local and international databases were searched using the key words "Occupational Injury", "Needle Stick Injury, " "Risk Factors, Health Care Workers" and "Iran." The inclusion criteria for articles were the availability of the full text, focus on causes of occupational injuries and needle-stick injuries, publication in Persian or English, and publication occurring in the 16year study period.Articles in languages other than Persian or English, those lacking clarity of methods, and those lacking the proper reporting of results were excluded.

Data Collection and Extraction
Searches were performed for all articles published in the 16year period of 2000 to 2016 in Persian or English on local databases (SID, Mag Iran, Iran Medex, Iranian Medical Library) as well as international databases (Google Scholar, ISI Web of Knowledge, Scopus, PubMed, and Science Direct).Data extracted from the relevant studies included author(s) name, publication year, location of research, sample size, and prevalence of common causes (needle as the common object and injections as the common activity).

Data Analysis
The extracted data was analyzed using STATA 11 software.I 2 was used to evaluate the heterogeneity of the data.The random effects model was used because of the heterogeneity of the results of the selected studies.
A total of 8703 HCWs and students were surveyed in the selected studies.The highest prevalence rates of needle as an associated factor of occupational injuries were reported by Nazmieh (79.9%),Kouhestani (76.92%), and Bijani (70.9%), and the lowest prevalence rates were reported by Mirzaei (33.3%),Gholami (35.71%), and Aghadoost (37.5%).The prevalence of NSI among Iranian HCWs with a sample size of 8703 was estimated to be 52.95%(95% CI: -46.05-59.84)using the random effect model (Figure 2).The funnel plot to assess publication bias for prevalence of needle as a common object in occupational injuries is presented in Figure 3.
The highest prevalence rates of injection as the cause of occupational injuries were reported by Parsapili (64.9%),Rakhshani (54.6%), and Vahedi (49.94%), and the lowest prevalence rates were reported by Gholami (14.47%),Ehsani (18.91%), and Adib-Hajbagheri (22.2%).The prevalence of injections among Iranian HCWs with a sample size of 8703 was estimated to be 33.56%(confidence interval 95%-27.43-37.90)using the random effect model (Figure 4).The funnel plot to assess publication bias for the prevalence of injections as a common activity in occupational injuries is presented in Figure 5.

Discussion
In this meta-analysis study, the analysis results suggested that needles and injections are the most common causes of occupational injuries in Iranian HCWs.The prevalence of NSIs among Iranian HCWs was estimated to be 52.95%(confidence interval 95%-46.05-59.84)using the random effect model.These results indicate the high prevalence of  the needle as the most common device causing injuries.In a study by Kebede et al in Ethiopia, the needle was reported as the most common device among HCWs (47.2%), 32 which is consistent with the current findings in Iran.As the needle is the most commonly used device in routine care by HCWs, the high prevalence of injuries caused by this device is reasonable.
Martins et al showed that syringe needles were responsible for 45.8% of injuries. 33The slight difference between the current findings and those of Martins et al can be attributed to different organizational and environmental settings in   different countries.In Japan, a study by Yoshikawa et al on 5463 cases showed that the disposable syringe was the most common device causing injuries in 25.4% of cases. 34sing safety equipment and following standard precautions are very important to decreasing device-related injuries. 34he frequency of NSIs is a major occupational health issue around the world, especially in countries with limited safety equipment resources. 35In the study by Smith et al among Japanese nurses, the needle was the common device in 31.3% of injuries. 36The high prevalence of NSIs in the current findings compared with other studies emphasizes the role of education and the importance of recapping and practicing strict precautionary actions after using devices with needles. 32he results of the current study showed a wide variation in the prevalence rates of injection-related injuries among HCWs in Iran.The prevalence of injection-related occupational injuries among Iranian HCWs was estimated to be 33.56%(confidence interval 95%-27.43-37.90)using the random effect model.This is higher than the prevalence of injectionrelated injuries reported by Martin et al. 33 In their study, they showed that injection was the most common cause of activity-related injuries among HCWs. 33In a study by Afridi et al in Pakistan, 41.9% of HCWs were injured while giving injections or drawing blood samples. 37Injection was the most common cause of activity-related injuries in the findings of the studies of Laishram et al, 38 Quien et al, 39 Nsubuga et al, 40 and Kebede et al. 32 Caution must be taken when comparing the current findings with those of the above-mentioned studies.This article is the analysis of 19 studies, while the other mentioned papers were  based on one study.Because of the high prevalence rates of device-related and activity-related injuries in Iranian HCWs, it is necessary to establish effective precautionary standards and safety measures to reduce occupational injuries among HCWs.
This meta-analysis has two limitations.First, because of the heterogeneity of the studies and the fact that this metaanalysis was restricted to studies on Iran, caution must be taken in interpreting and generalizing the findings to other health care settings around the world.Secondly, differences in participant occupation, gender, sample size, location, type of hospital (public or private), and experiences of HCWs require that the current findings be interpreted with caution.

Conclusions
This study found the overall prevalence rates of needlerelated and injection-related injuries among HCWs in Iran to be 52.95% and 33.56%, respectively.The impact occupational injuries have on the quality of patient care, the safety of HCWs, and health care costs demand that effective measures be applied to prevent or decrease the frequency of occupational injuries.

Figure 1 .
Figure 1.Flow Chart of the Study.
-text articles assessed for eligibility 19 of studies included in meta-analysis 41 of full-text articles excluded because of lake of inclusion criteria 3610 of records excluded after checking of title, abstract and research question 342 of records excluded after checking of duplication

Figure 2 .
Figure 2. Needle Prevalence Based on the Reviewed Studies.Horizontal lines around the main mean show the confidence interval of 95% for each study.The dotted line in the middle indicates the estimated total prevalence, and the lozenge shows the confidence interval of the total prevalence of needle-related injuries.

Figure 3 .
Figure 3. Funnel Plot to Assess Publication Bias for Prevalence of Needle as a Common Object in Occupational Injuries.

Figure 4 .
Figure 4. Prevalence of Injections Based on the Reviewed Studies.Horizontal lines around the main mean show the confidence interval of 95% for each study.The dotted line in the middle indicates the estimated total prevalence, and the lozenge shows the confidence interval of the total prevalence of injection-related injuries.

Figure 5 .
Figure 5. Funnel Plot to Assess Publication Bias for Prevalence of Injections as Common Activity in Occupational Injuries.

Table 1 .
Characteristics of Reviewed Studies