Numeracy levels influence shared decision-making and surgical outcomes: A scoping review of the literature

Published:January 04, 2023DOI:


      • Many patients perform poorly on simple numeracy assessments.
      • This scoping review highlights the high degree of data heterogeneity among numeracy studies.
      • There is a lack of standardization among numeracy tools and measurements.
      • Patient numeracy is important for preoperative counseling, risk assessment and surgical outcomes.
      • Future research must integrate communication interventions following numeracy assessments.



      Health literacy has been widely studied with regard to medical decision-making and health care access, however research regarding numeracy - the ability to comprehend and attach meaning to numbers - is more limited.


      A scoping review following PRISMA guidelines was conducted. We screened 132 abstracts and 12 studies were included in the analysis.


      Surgical population numeracy ranged from 47 to 86.1%. We found heterogeneity in the scales used to measure numeracy and the cutoff values used to define adequate numeracy. Low numeracy was shown to influence the accuracy of patients’ responses to quality of life measures used to determine surgical outcomes and was associated with patient overestimation of pre-operative risk. Adequate numeracy was correlated with improved outcomes 2–4 years after bariatric surgery.


      Patient numeracy is generally poor and has important implications for pre-operative risk understanding, accuracy of health measurement tools and long-term surgical outcomes.


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