Understanding the Harms and Benefits of Cancer Screening: A Model of Factors That Shape Informed Decision Making.
OBJECTIVE
Decisions about cancer screenings often involve the consideration of complex and counterintuitive evidence. We investigated psychological factors that promote the comprehension of benefits and harms associated with common cancer screenings and their influence on shared decision making.


METHODS
In experiment 1, 256 men received information about PSA-based prostate cancer screening. In experiment 2, 355 women received information about mammography-based breast cancer screening. In both studies, information about potential screening outcomes was provided in 1 of 3 formats: text, a fact box, or a visual aid (e.g., mortality with and without screening and rate of overdiagnosis). We modeled the interplay of comprehension, perceived risks and benefits, intention to participate in screening, and desire for shared decision making.


RESULTS
Generally, visual aids were the most effective format, increasing comprehension by up to 18%. Improved comprehension was associated with 1) superior decision making (e.g., fewer intentions to participate in screening when it offered no benefit) and 2) more desire to share in decision making. However, comprehension of the evidence had a limited effect on experienced emotions, risk perceptions, and decision making among those participants who felt that the consequences of cancer were extremely severe.


CONCLUSIONS
Even when information is counterintuitive and requires the integration of complex harms and benefits, user-friendly risk communications can facilitate comprehension, improve high-stakes decisions, and promote shared decision making. However, previous beliefs about the effectiveness of screening or strong fears about specific cancers may interfere with comprehension and informed decision making.
['Petrova|Dafina|D|', 'Garcia-Retamero|Rocio|R|', 'Cokely|Edward T|ET|']
D000293:Adolescent D000328:Adult D000368:Aged D001943:Breast Neoplasms D032882:Comprehension D003657:Decision Making D005260:Female D006801:Humans D008297:Male D008875:Middle Aged D011471:Prostatic Neoplasms D055815:Young Adult
cancer screening shared decision making emotions risk communication risk literacy