### Abstract

Tsai S P (Gulf Oil Corporation, Medical and Health Resources Division, PO Box 2100, Houston, Texas 77252, USA) and Wen C P. The impact of competing risks on relative risk in occupational cohort studies. International Journal of Epidemiology 1984, 13: 518- 525.This paper develops a method for adjustment of competing causes of death in the calculation of relative risk. It has identified three factors determining the significance of competing risks: (1) the magnitude of the overall mortality risk of the study population; (2) differential risk (or the adjustment factor) for mortality other than cause of interest between two populations; and (3) age intervals used in the mortality calculation. Thus, the impact of competing risks is increased if the study cohort has a high mortality risk, if the mortality other than the cause of interest has a large differential risk or if the mortality calculation uses wide age intervals. Two examples from a refinery cohort and the US national population show that among certain age groups unadjusted for competing risks the relative risk is overestimated by 9%. The impact of competing risks in these two particular examples is relatively small. Furthermore, if relative risk is expressed in terms of the ratio of mortality rates, competing risks can be ignored.

Original language | English (US) |
---|---|

Pages (from-to) | 518-525 |

Number of pages | 8 |

Journal | International Journal of Epidemiology |

Volume | 13 |

Issue number | 4 |

DOIs | |

State | Published - Dec 1984 |

Externally published | Yes |

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### ASJC Scopus subject areas

- Statistics, Probability and Uncertainty
- Applied Mathematics
- Physiology (medical)
- Reproductive Medicine
- Obstetrics and Gynecology
- Epidemiology

### Cite this

*International Journal of Epidemiology*,

*13*(4), 518-525. https://doi.org/10.1093/ije/13.4.518

**The impact of competing risks on relative risk in occupational cohort studies.** / Tsai, Shan Pou; Wen, C. P.

Research output: Contribution to journal › Article

*International Journal of Epidemiology*, vol. 13, no. 4, pp. 518-525. https://doi.org/10.1093/ije/13.4.518

}

TY - JOUR

T1 - The impact of competing risks on relative risk in occupational cohort studies

AU - Tsai, Shan Pou

AU - Wen, C. P.

PY - 1984/12

Y1 - 1984/12

N2 - Tsai S P (Gulf Oil Corporation, Medical and Health Resources Division, PO Box 2100, Houston, Texas 77252, USA) and Wen C P. The impact of competing risks on relative risk in occupational cohort studies. International Journal of Epidemiology 1984, 13: 518- 525.This paper develops a method for adjustment of competing causes of death in the calculation of relative risk. It has identified three factors determining the significance of competing risks: (1) the magnitude of the overall mortality risk of the study population; (2) differential risk (or the adjustment factor) for mortality other than cause of interest between two populations; and (3) age intervals used in the mortality calculation. Thus, the impact of competing risks is increased if the study cohort has a high mortality risk, if the mortality other than the cause of interest has a large differential risk or if the mortality calculation uses wide age intervals. Two examples from a refinery cohort and the US national population show that among certain age groups unadjusted for competing risks the relative risk is overestimated by 9%. The impact of competing risks in these two particular examples is relatively small. Furthermore, if relative risk is expressed in terms of the ratio of mortality rates, competing risks can be ignored.

AB - Tsai S P (Gulf Oil Corporation, Medical and Health Resources Division, PO Box 2100, Houston, Texas 77252, USA) and Wen C P. The impact of competing risks on relative risk in occupational cohort studies. International Journal of Epidemiology 1984, 13: 518- 525.This paper develops a method for adjustment of competing causes of death in the calculation of relative risk. It has identified three factors determining the significance of competing risks: (1) the magnitude of the overall mortality risk of the study population; (2) differential risk (or the adjustment factor) for mortality other than cause of interest between two populations; and (3) age intervals used in the mortality calculation. Thus, the impact of competing risks is increased if the study cohort has a high mortality risk, if the mortality other than the cause of interest has a large differential risk or if the mortality calculation uses wide age intervals. Two examples from a refinery cohort and the US national population show that among certain age groups unadjusted for competing risks the relative risk is overestimated by 9%. The impact of competing risks in these two particular examples is relatively small. Furthermore, if relative risk is expressed in terms of the ratio of mortality rates, competing risks can be ignored.

UR - http://www.scopus.com/inward/record.url?scp=0021746553&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0021746553&partnerID=8YFLogxK

U2 - 10.1093/ije/13.4.518

DO - 10.1093/ije/13.4.518

M3 - Article

VL - 13

SP - 518

EP - 525

JO - International Journal of Epidemiology

JF - International Journal of Epidemiology

SN - 0300-5771

IS - 4

ER -