[Cohort studies on cancer mortality of digestive system among workers exposed to asbestos: a meta-analysis].

Objective: To determine if there are excessive risks of malignant tumors or not among workers exposed to asbestos by applying a meta-analysis technique.

Methods: All data meeting the criteria of cohort studies on cancer mortality of digestive system among workers exposed to asbestos would be incorporated into the meta-analysis. The pooled standardized mortality ratios (SMR) and their corresponding 95% confidence intervals (CIs) for main cancer sites of digestive system were calculated by using two approaches of un-weighted ratio and random effects model.

Cohort studies on cancer mortality among workers exposed only to chrysotile asbestos: a meta-analysis.

Objective: To determine whether there was excessive risk of cancer among workers exposed to chrysotile fiber alone by applying a meta-analysis technique.

Methods: All data meeting the criteria of cohort studies on cancer mortality among workers exposed only to chrysotile were incorporated into meta-analysis. Pooled standardized mortality ratios (SMRs) and their corresponding 95% confidence intervals (CIs) for main cancer sites were calculated using two approaches of unweighted ratio and random effect model.

[A meta-analysis of cohort studies on cancer mortality among workers exposure to chrysotile fiber alone].

Objective: To determine there was excessive risk of malignant tumors or not among workers exposure to chrysotile fiber alone by applying a meta-analysis technique.

Methods: All data meeting the criteria of cohort studies on cancer mortality among workers exposed only to chrysotile would incorporate into the meta-analysis. The pooled standardized mortality ratios (SMR) and their corresponding 95% confidence intervals (95% CI) for main cancer sites were calculated using two approaches of unweighted ratio and random effects model.