Gaissmaier, W., Giese, H., Galesic, M., Garcia-Retamero, R., Kasper, J., ... Heesen, C. (2018). Numeracy of multiple sclerosis patients: A comparison of patients from the PERCEPT study to a German probabilistic sample. Patient Education and Counseling, 101(1), 74–78 doi: 10.1016/j.pec.2017.07.018

OBJECTIVE: A shared decision-making approach is suggested for multiple sclerosis (MS) patients. To properly evaluate benefits and risks of different treatment options accordingly, MS patients require sufficient numeracy - the ability to understand quantitative information. It is unknown whether MS affects numeracy. Therefore, we investigated whether patients' numeracy was impaired compared to a probabilistic national sample.
METHODS: As part of the larger prospective, observational, multicenter study PERCEPT, we assessed numeracy for a clinical study sample of German MS patients (N=725) with a standard test and compared them to a German probabilistic sample (N=1001), controlling for age, sex, and education. Within patients, we assessed whether disease variables (disease duration, disability, annual relapse rate, cognitive impairment) predicted numeracy beyond these demographics.
RESULTS: MS patients showed a comparable level of numeracy as the probabilistic national sample (68.9% vs. 68.5% correct answers, P=0.831). In both samples, numeracy was higher for men and the highly educated. Disease variables did not predict numeracy beyond demographics within patients, and predictability was generally low.
CONCLUSION: This sample of MS patients understood quantitative information on the same level as the general population.
PRACTICE IMPLICATIONS: There is no reason to withhold quantitative information from MS patients.