ADOLESCENTS MISINTERPRETATION OF HEALTH RISK PROBABILITY-EXPRESSIONS

Objective. To determine if differences exist between adolescents and p hysicians in their numerical translation of 13 commonly used probabili ty expressions (eg, possibly, might). Design. Cross-sectional. Setting . Adolescent medicine and pediatric orthopedic outpatient units. Parti cipants. 150 adolescents and 51 pediatricians, pediatric orthopedic su rgeons, and nurses. Measurement. Numerical ratings of the degree of ce rtainty implied by 13 probability expressions (eg, possibly, probably) . Results. Adolescents were significantly more likely than,physicians to display comprehension errors, reversing or equating the meaning of terms such as probably/possibly possibly and likely/possibly. Numerica l expressions of uncertainty (eg, 30% chance) elicited less variabilit y in ratings than lexical expressions of uncertainty (eg, possibly). C onclusion. Physicians should avoid using probability expressions such as probably, possibly, and likely when communicating health risks to c hildren and adolescents. Numerical expressions of uncertainty may be m ore effective for conveying the likelihood of an illness than lexical expressions of uncertainty (eg, probably).