Psychometric properties of instruments for assessing adherence to oral antineoplastic agents: a COSMIN systematic review.

INTRODUCTION

Oral antineoplastic therapies have increasingly become a mainstay therapy for various cancers. Selecting the most suitable instrument for assessing adherence to oral antineoplastic agents (OAAs) in cancer patients is crucial to tracking patients' medication compliance. This review is the first to identify available instruments for assessing adherence to OAAs and examine the quality of their psychometric properties.

METHODS

Following the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, eight electronic databases (PubMed, Embase, Web of Science, Cumulative Index to Nursing and Allied Health Literature (CINAHL), China National Knowledge Infrastructure (CNKI), Wanfang, Weipu, and Sinomed) were systematically searched for relevant studies published from inception until December 31, 2023. The study protocol received registration with the International Prospective Register of Systematic Reviews (CRD42024546402).

RESULTS

Eight studies assessing eight identified instruments were included. Four instruments were universal to cancer patients treated with any OAA; the other four instruments were only suitable for a specific type of OAA. None of the studies explored measurement error, cross-cultural validity/measurement invariance, and responsiveness of the instruments. All the instruments failed to meet the COSMIN criteria. Eventually, seven instruments were weakly recommended for use to assess OAA adherence, and one was not recommended for assessing OAA adherence due to high-quality evidence for insufficient internal consistency.

CONCLUSION

The selection of the most appropriate instrument to assess adherence to OAAs depends on its psychometric properties and relevance to the type of OAA. Eight identified instruments for assessing adherence to OAAs demonstrated limited reliability and validity. Further thorough validation is required for all included instruments. Instruments with rigid measurement properties are urgently needed to be developed to assess OAA adherence in cancer patients.