Bach model: the 1-year probability of lung cancer diagnosis.
Model described by Bach et al. predicts the probability of being diagnosed with lung cancer within the next year. The model was developed using subjects enrolled in the Carotene and Retinol Efficacy Trial (CARET); a large, randomized trial of lung cancer prevention. 
Research authors: Peter B. Bach, Michael W. Kattan, Mark D. Thornquist, Mark G. Kris, Ramsey C. Tate, Matt J. Barnett, Lillian J. Hsieh, Colin B. Begg
Details Formula Study characteristics Files & References
Model author
Model ID
Revision date
MeSH terms
  • Lung Cancer
  • Smoking
  • Asbestos
  • Model type
    Custom model (Calculation)

    Additional information

    A total of 18 314 individuals were randomly assigned to receive either placebo or the study drug (30 mg/day beta-carotene and 25 000 IU/day retinyl palmitate). Randomization for the pilot study began in June 1985, followed by randomization for the full-scale study in June 1989; study accrual ended in September 1994. The intervention itself was stopped in January 1996 after preliminary results revealed definitive evidence of no benefit and substantial evidence of possible harm, but study subjects continue to be followed annually by mail, with additional data collection on reported endpoints. The subjects included in our analyses were the 18 172 individuals who had a documented history of current or former smoking. Our analyses of the CARET data were approved by the Institutional Review Board at the Fred Hutchinson Cancer Research Center, Seattle, WA.

    Study Population

    Total population size: 18172
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    Females: {{ model.numberOfFemales }}

    Categorical characteristics

    Name Subset / Group Nr. of patients
    All Heavy Smoker cohort 14254
    Asbestos cohort 3918
    Age at study entry 44-54 6317
    55-60 4638
    61-75 7217
    Smoking status Former 7168
    Current 11004
    Race White 16939
    Black 524
    Hispanic 273
    Asian/Pacific Islander 205
    American Indian/Alaskan 148
    Other/Unknown 83
    Arm Placebo 8825
    Intervention 9347
    Enrollment site Seattle, WA 6655
    Baltimore, MD 822
    New Haven, CT 1041
    Portland, OR 4564
    San Fransisco, CA 866
    Irvine, CA 4224
    Education No high school diploma 2044
    High school 4320
    Some college 6226
    Completed college 3737
    Unknown 1845
    Bach model: the 1-year probability of lung cancer diagnosis.
    Refer to Intended Use for instructions before use
    Evidencio B.V., Irenesingel 19, 7481 GJ, Haaksbergen, the Netherlands

    Related files

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    Supporting Publications

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    Notes are only visible in the result download and will not be saved by Evidencio

    The 1-year probability of being diagnosed with lung cancer is: %

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    Outcome stratification

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    Conditional information

    Result interpretation

    This model should be used together with the Bach Model: The 1-year probability of death in the absene of lung cancer diagnosis. Iterative use of both models estimates the probability of lung cancer diagnosis over a longer time horizon than 1 year. 

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    Calculations alone should never dictate patient care, and are no substitute for professional judgement. See our full disclaimer.

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