Table 5 Individual and meta‐analysis results of occupational TCE exposure and non‐Hodgkin's Lymphoma for Group I sub‐cohorts by shortest and longest cumulative exposure and duration categories of exposure.
| Reference and exposure level | Type of risk estimate | Shortest exposure category | Longest exposure category | ||
|---|---|---|---|---|---|
| Risk estimate | 95% CI | Risk estimate | 95% CI | ||
| Cumulative exposure (intensity × duration) | |||||
| Blair et al, 199829 | |||||
| TCE exposed sub‐cohort | |||||
| Shortest: <5 unit‐years | |||||
| Longest: >25 unit‐years (units = intensity/year × duration/day for each job × frequency) | RR | 0.85 | 0.39 to 1.62 | 0.98 | 0.45 to 1.86 |
| Hansen et al, 200125 | |||||
| Cumulative TCE exposed sub‐cohort | |||||
| Shortest: <1080 months × mg/m3 | |||||
| Longest: ⩾1080 months × mg/m3 | SIR | 3.90 | 0.80 to 11.0 | 3.10 | 0.6 to 9.10 |
| Morgan et al, 199830* | |||||
| Shortest: cumulative and low TCE exposed sub‐cohort | |||||
| Longest: cumulative and highly TCE exposed sub‐cohort (based on intensity and duration of exposure) | RR | 2.25 | 0.46 to 11.1 | 0.81 | 0.10 to 2.20 |
| Summary risk estimate: random effects model | SRRE | 1.8 | 0.62 to 5.26 | 1.41 | 0.61 to 3.23 |
| Test for heterogeneity | p value | 0.041 | 0.179 | ||
| Duration of exposure (time) | |||||
| Boice et al, 199935 | |||||
| TCE exposed sub‐cohort | |||||
| Shortest: 1–4 years exposed | |||||
| Longest: ⩾5 years exposed | RR | 1.33 | 0.64 to 2.78 | 1.62 | 0.82 to 3.22 |
| Raaschou‐Nielsen et al, 200326 | |||||
| Cumulative TCE exposed sub‐cohort | |||||
| Shortest: 1–4.9 years | |||||
| Longest: ⩾5 years | SIR | 1.50 | 1.10 to 2.10 | 1.60 | 1.10 to 2.20 |
| Summary risk estimate: random effects model | SRRE | 1.47 | 1.08 to 2.0 | 1.60 | 1.20 to 2.10 |
| Test for heterogeneity | p value | 0.771 | 0.974 | ||
*Results for ICD codes 200 and 202.