gms | German Medical Science

19. Deutscher Kongress für Versorgungsforschung

Deutsches Netzwerk Versorgungsforschung e. V.

30.09. - 01.10.2020, digital

The challenge to define a relevant change in Medication Appropriateness Index score in older adults

Meeting Abstract

  • Laura Krisch - Institute of Nursing Science and Practice, Paracelsus Medical University, Salzburg, Österreich
  • Angelika Mahlknecht - Institute of General Practice, Family Medicine and Preventive Medicine, Paracelsus Medical University, Salzburg, Österreich
  • Ulrike Bauer - Institute of Nursing Science and Practice, Paracelsus Medical University, Salzburg, Österreich
  • Nadja Nestler - Institute of Nursing Science and Practice, Paracelsus Medical University, Salzburg, Österreich
  • Georg Hempel - Department of Pharmaceutical and Medical Chemistry – Clinical Pharmacy, Westfaelische Wilhelms-University, Münster, Deutschland
  • Jürgen Osterbrink - Institute of Nursing Science and Practice, Paracelsus Medical University, Salzburg, Österreich
  • Maria Flamm - Institute of General Practice, Family Medicine and Preventive Medicine, Paracelsus Medical University, Salzburg, Österreich

19. Deutscher Kongress für Versorgungsforschung (DKVF). sine loco [digital], 30.09.-01.10.2020. Düsseldorf: German Medical Science GMS Publishing House; 2020. Doc20dkvf235

doi: 10.3205/20dkvf235, urn:nbn:de:0183-20dkvf2357

Veröffentlicht: 25. September 2020

© 2020 Krisch et al.
Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). Lizenz-Angaben siehe http://creativecommons.org/licenses/by/4.0/.


Gliederung

Text

Background: The Medication Appropriateness Index (MAI) is considered the most reliable and valid implicit instrument to measure medication appropriateness and is mostly used as a progression parameter in RCTs. We applied the MAI in an interventional study [1] that aimed to improve drug therapy safety in residents of nursing homes by means of an intervention that combined training of professional groups, the use of an online platform, that structured communication between health care professions and a medication review. Thereby we faced some challenges regarding the interpretation of the changes in MAI-score – it’s magnitude as well as its practical or clinical significance.

Aim: The aim of this contribution is to investigate and discuss different possibilities for interpretation of this value and to encourage a debate on that topic.

Methods: We address this issue by discussing a content-based, a distribution-based and a context-based approach.

Results: The content-based approach focuses on content and construct of the scale. Typically MAI score per drug and drug count form a summated score per subject. Dividing the patient’s score by patient’s drug count would lead to a comparable and standardized value. The scale’s items are weighted in their importance from 1 to 3 construing a 3-point change to be qualitatively meaningful. For more transparency a content-based cut-off should be determined by an expert discussion.

The distribution-based approach concentrates on the comparability between studies, as MAI change score, mostly reported in RCTs using MAI, is not standardized. It is necessary to report standardized effect sizes (e.g. Cohen’s d) including confidence intervals. A small effect size (d=0.2) may also be used as standardized distributional measure of the minimum clinically important difference (MCID). Still the clinical meaning remains unsettled.

The context-based approach focuses on the correspondence between a change in test score and in patient outcomes. Context-dependent even small effects may be meaningful by triggering significant consequences. The MAI change is strongly related to pre-interventional appropriateness. A RCT uses the mean difference of 3.88 points extracted from a Cochrane review as cut-off for a major benefit. It’s meaning for patient-relevant outcomes remains unclear.

Discussion: As each of the presented approaches has limitations, combining them can be useful to interpret MAI results. It does not seem to be conducive to determine one single cut-off but rather to interpret the change considering the content of the scale, to include a context by adducting comparable studies with external criteria and to report standardized measures of effect size

Implications: Further research is needed in order to determine a clinically relevant cut-off for a reduction in MAI score that may vary according to setting, intervention and population.


References

1.
Mahlknecht A, Krisch L, Nestler N, Bauer U, Letz N, Zenz D, Schuler J, Fährmann L, Hempel G, Flamm M, Osterbrink J. Impact of training and structured medication review on medication appropriateness and patient-related outcomes in nursing homes: results from the interventional study InTherAKT. BMC Geriatr. 2019 Sep;19(1):257. DOI: 10.1186/s12877-019-1263-3 Externer Link