Table 2 Inclusion and exclusion criteria for the realist review

Populations: all participants aged 50 years and over with multimorbidity (two conditions or more)

Studies focused solely on toxicity reactions

Interventions (concepts/process and theory)—any systematic intervention process used to safely withdraw medications in older people with multimorbidity and polypharmacy and the outcomes used to measure the effectiveness of these strategies.

Context: documents conducted in any appropriate setting (general practice/pharmacy/home setting)

Documents from low- and middle-income countries, studies not published in English

Study design: Any comparative studies including RCTs, cohort or case control studies, qualitative studies and grey literature