EXAMINING DECISION-MAKING FOR CANCER SCREENING: COMPARISON BETWEEN THE CHARACTERISTICS OF JAPANESE AND US ADULTS

Purpose: The DECISIONS Study (Zikmund-Fisher B.J., et al. 2010) shed light on the characteristics of US adults regarding 9 common medical decisions (MD).  A comparison with non-US countries would advance this research, enable examination of the problems related to medical decision-making (MDM), and facilitate improvement of cancer screening rates. This study explores the structure of MDM related to cancer screening by comparing the traits of adults in Japan and the US.

Method: Internet survey data was collected from 2017 Japanese adults in their 40s to 60s who made decisions on cancer screening within the last three years (mammography: 626; colonoscopy: 1226 (male: 652; female: 574); PSA test: 165). The questions covered topics such as the importance of early detection of cancer, precision, cost and discomfort associated with the screening, their assessment of the health care provider's explanation regarding screening, and their satisfaction with their decision.

Result: Logistic regression analysis was applied to determine the factors related to those who were satisfied/confident with their decision and those who were not (Japanese/US adults). The common variable among the cancer types determining satisfaction with their decision was the health care provider's explanation (mammography: OR=2.068, p<0.01; colonoscopy: male OR=23.404, p<0.01; female OR=1.416, p<0.01; PSA test: OR=1.420, p<0.01), while confidence in their decision was related to early detection of the cancer (mammography: OR=1.302, p<0.01; colonoscopy: male OR=1.238, p<0.05, female OR=1.416,p<0.01; PSA test: OR=1.420, p<0.01). There was a common trend between Japanese and US adults regarding the factors affecting decision-making to undergo mammography: the important factors for Japanese subjects were the health care provider's explanation, precision of screening, early detection of cancer, and discomfort related with screening, while for US subjects they were the early detection of cancer, fear of getting cancer, shared decision-making, and discomfort related to screening.

Conclusion: In conclusion, comparison of decision-making for cancer screening in different countries would help improve cancer screening rates: the effectiveness of early detection of cancer should be emphasized for Japanese, while shared decision-making could potentially encourage US females to undergo screening colonoscopies, considering the differences in the factors that affect the confidence in decision-making regarding undergoing mammography and colonoscopy in the US.