Tendency of cumulative incidence of coal workers' pneumoconiosis in a coal mine in Huaibei City 
	    		
		   		
		   			
		   		
	    	
    	 
    	10.11763/j.issn.2095-2619.2017.05.005
   		
        
        	
        	
        	
        		- Author:
	        		
		        		
		        		
			        		Jian MENG
			        		
			        		
			        		
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			        		Xinping DING
			        		
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			        		Jiao CHEN
			        		
			        		
			        		
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			        		Fengtao CUI
			        		
			        		
			        		
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			        		Jianhua LIU
			        		
			        		
			        		
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			        		Fuhai SHEN
			        		
			        		
			        		
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			        		Author Information
			        		
		        		
		        		
			        		
			        		
			        			1. School of Public Health,North China University of Science and Technology Tangshan,Hebei 063210,China
			        		
		        		
	        		
        		 
        	
        	
        	
        		- Publication Type:Journal Article
 
        	
        	
        		- Keywords:
        			
	        			
	        				
	        				
			        		
				        		Coal worker's pneumoconiosis;
			        		
			        		
			        		
				        		Dust;
			        		
			        		
			        		
				        		Incidence regularity;
			        		
			        		
			        		
				        		Cumulative incidence rate
			        		
			        		
	        			
        			
        		
 
        	
            
            
            	- From:
	            		
	            			China Occupational Medicine
	            		
	            		 2017;44(05):557-561
	            	
            	
 
            
            
            	- CountryChina
 
            
            
            	- Language:Chinese
 
            
            
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		        	Abstract:
			       	
			       		
				        
				        	 OBJECTIVE: To analyze the tendency of incidence in coal workers' pneumoconiosis( CWP) in different time of dust exposure and different types of work in a mining enterprise in Huaibei City. METHODS: A total of 12 152 dust exposed workers who worked from 1970 to 2014 in a mining enterprise in Huaibei City were chosen as study subjects by judgment sampling method. They were divided into 2 cohorts were formed according to initial year of dust exposure( 1970-,1980-),and 4 group according to the type of work( tunneling,mining,combining and helping). Life table method was adopted to calculate cumulative life-incidence of CWP in each cohort. RESULTS: Among 12 152 workers,there were 594 of them diagnosed as CWP patients with a 4. 89% of incidence. During the same 34-year-observation period,the cumulative CWP incidence of 1970-cohort was higher than that of the 1980 s( 8. 03% vs 5. 45%,P < 0. 01). The cumulative CWP incidence of tunneling,mining,combining and helping workers were 69. 33%,40. 53%,36. 66% and 19. 70% by 2014,respectively. The cumulative incidence of CWP in tunneling group started to rise from the 14-year-observation window,mining's from 16-year-observation window,combining and helping workers from 18-year-observation window. Among the workers in 1970-cohort at the 34-year-observation window,the CWP cumulative incidence in mining group was the highest( 33. 83%,P < 0. 004),and combining's was the lowest( 2. 28%,P < 0. 004). Among the workers in 1970-cohort at the 44-year-observation window,the CWP cumulative incidence in tunneling group was the highest( 66. 66%,P < 0. 004),and helping's was the lowest( 27. 24%,P < 0. 004). Among the workers in 1980-cohort at the 34-year-observation window,the CWP cumulative incidence in tunneling group was the highest( 29. 87%,P < 0. 004). CONCLUSION: The cumulative incidence of CWP patients was slowed down with prolonged dust exposure starting time. There were differences among different types of workers with different starting time of dust exposure.