Long-term health experience of jet engine manufacturing workers: V. Issues with the analysis of non-malignant central nervous system neoplasms.
OBJECTIVE
We attempted to examine non-malignant central nervous system (CNS) neoplasms incidence rates for workers at 8 jet engine manufacturing facilities in Connecticut. The objective of this manuscript is to describe difficulties encountered regarding these analyses to aid future studies.


METHODS
We traced the cohort for incident cases of CNS neoplasms in states where 95% of deaths in the total cohort occurred. We used external and internal analyses in an attempt to obtain the true risk of non-malignant CNS in the cohort. Because these analyses were limited by data constraints, we conducted sensitivity analyses, including using state driver's license data to adjust person-year stop dates to help minimize underascertainment and more accurately determine cohort risk estimates.


RESULTS
We identified 3 unanticipated challenges: case identification, determination of population-based cancer incidence rates, and handling of case underascertainment. These factors precluded an accurate assessment of non-malignant CNS neoplasm incidence risks in this occupational epidemiology study.


CONCLUSIONS
The relatively recent (2004) mandate of capturing non-malignant CNS tumor data at the state level means that, in time, it may be possible to conduct external analyses of these data. Meanwhile, similar occupational epidemiology studies may be limited to descriptive analysis of the non-malignant CNS case characteristics.
Department of Biostatistics, University of Pittsburgh, Pittsburgh, PA, USA. jeanine@cobe.pitt.edu
Jeanine M
JM
Buchanich
Ada O
AO
Youk
Gary M
GM
Marsh
Kathleen J
KJ
Kennedy
Steven E
SE
Lacey
Roger P
RP
Hancock
Nurtan A
NA
Esmen
Michael A
MA
Cunningham
Frank S
FS
Leiberman
Mary Lou
ML
Fleissner
D000401:Aircraft; D016543:Central Nervous System Neoplasms / Q000453:epidemiology*; D015331:Cohort Studies; D003237:Connecticut / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007221:Industry; D009784:Occupational Diseases / Q000453:epidemiology*; D016273:Occupational Exposure / Q000706:statistics & numerical data*; D011159:Population Surveillance / Q000379:methods; D012042:Registries / Q000706:statistics & numerical data*; D018570:Risk Assessment