ABSTRACT
AIM: To validate and standardize the Brazilian version of the Medication Regimen Complexity Index (MRCI) for older adults in primary healthcare. METHODS: A cross-sectional methodological study was carried out with elderly patients attending primary healthcare centers in southeastern Brazil. Convergent validity was tested by correlating MRCI scores with medication number. Divergent validity was tested by correlating MRCI scores with age, sex, cognition, and basic and instrumental activities of daily living. Reliability was assessed by interrater and test-retest reliability. Regarding standardization, percentiles were calculated for the total MRCI scores. RESULTS: A total of 227 older adults were included, with a mean age of 71.4 years (standard deviation 7.5 years) and mostly women (70.9%). There was a correlation between MRCI scores and medication number (rho = 0.890; P = 0.000). There was no correlation between MRCI scores and age (P = 0.192), sex (P = 0.052), cognition (P = 0.369), and basic (P = 0.682) and instrumental (P = 0.582) activities of daily living. High interrater (intraclass correlation coefficient = 0.98; rho = 0.991) and test-retest (intraclass correlation coefficient = 0.996; rho = 0.985) reliability was obtained. The following complexity was considered: low, MRCI ≤ 9.0 points; average 0.9 < MRCI ≤ 16.5 points; and high, MRCI > 16.5 points. CONCLUSIONS: MRCI showed satisfactory psychometric qualities for measuring regimen complexity of older adults attending the primary healthcare centers evaluated. Standardization might increase the applicability of MRCI to the health research context. Geriatr Gerontol Int 2018; 18: 853-859.
