JU INSIGHT: Impact of Left-digit Age Bias in the Treatment of Localized Prostate Cancer
By: Aaron Brant, MD; Patrick Lewicki, MD; Xian Wu, MPH; Christina Sze, MD, MS; Jeffrey P. Johnson, MD; Spyridon P. Basourakos, MD; Camilo Arenas-Gallo, MD; Daniel Shoag, PhD; Christopher E. Barbieri, MD, PhD; Nicholas G. Zaorsky, MD, MS; Jonathan E. Shoag, MD | Posted on: 01 Nov 2022
Brant A, Lewicki P, Wu X, et al. Impact of left-digit age bias in the treatment of localized prostate cancer. J Urol. 2022;208(5):997-1006.
Study Need and Importance
Left-digit bias is a phenomenon in which the leftmost digit of a number disproportionately influences decision making. Left-digit bias towards patient age has been shown to influence treatment decisions in health care. We explored treatment recommendations made for patients with localized prostate cancer in 2 large national databases to determine if left-digit bias towards patient age affected treatment recommendations in this subset of patients.
What We Found
For patients with localized prostate cancer in both the National Cancer Database (NCDB) and Surveillance, Epidemiology, and End Results (SEER), discontinuities from age 69 to 70 were found in the proportion of patients recommended for radiation therapy and radical prostatectomy, with increased recommendations for radiation therapy (NCDB effect size: 3.1%, P < .01; SEER effect size: 2.2%, P < .01) and decreased recommendations for radical prostatectomy (NCDB effect size: −2.7%, P < .01; SEER effect size: −1.4%, P < .01; see Figure). Significant discontinuity in recommendations for radiation therapy and prostatectomy from age 69 to 70 was observed in both White and non-White patients, and in patients with Charlson Comorbidity index of 0.
Prostate-specific antigen was not available in all patients and thus was not used in risk stratification. We could not adjust for patient frailty, which is likely to influence treatment recommendations. Due to the retrospective nature of the study, there may be biases in patient selection and errors in charting that influence results.
In this study of SEER and NCDB patients with clinically localized prostate cancer, left-digit age change from 69 to 70 was associated with disproportionately increased recommendations for radiation therapy and disproportionately decreased recommendations for radical prostatectomy, affecting 5.8% of cases at age 70 in the NCDB cohort and 3.6% of cases at age 70 in the SEER cohort. Physicians should be aware of this cognitive bias potential when treating patients with prostate cancer.