Messerli 2016.

Study characteristics
Methods	Aim of study: to investigate the impact of the polymedication check (PMC) on patients on polypharmacy Study design: RCT (individual allocation) Number of arms/groups: 2
Participants	Description: patient/consumer Geographic location: Switzerland Setting: community pharmacy Inclusion criteria: > 18 years, ≥ 4 prescribed drugs over ≥ 3 months Exclusion criteria: living in retirement home, prior PMC, receiving weekly dosing aids filled by the pharmacy or another person, cognitive impairment, move or death, insufficient knowledge of written and spoken German or French Number of participants randomised: 450 (218, 232) Number of participants included in analysis: 372 completed; 450 in analysis Age: mean ± SD 67.2 ± 11.52 vs 67.1 ± 11.56 Gender: female: 118 (54.1%) vs 125 (53.9%) Ethnicity: not specified. Number of medications: long‐term oral medications (excluding on‐demand and self‐medication): 6.8 ± 2.92 (range 1 to 19) Frailty/Functional impairment: Disabilities of the Arm, Shoulder and Hand (DASH‐4) score: 4.9 ± 2.01 vs 4.9 ± 1.83 Cognitive impairment: cognitive impairment excluded Comorbidities: not specified
Interventions	Group 1 ‐ Polymedication check (PMC): face‐to‐face counselling with pharmacist. Pharmacist screened all meds, checked for knowledge gaps and pharmaceutical care issues (e.g. handling, adherence). Pharmacist documented all resulting interventions (e.g. GP consultations, implementation of weekly dose reminder systems). Education and medication plan could also be provided when necessary. PMC occurred at T0 and T28 (28 weeks = study end) Group 2 ‐ Usual care: no intervention or T0 documentation. Did receive PMC at 28 weeks (study end) Co‐intervention: N/A Provider: pharmacist (appropriately trained) Where: community pharmacy (separate area, i.e. consulting room) When and how often: T0 (intervention) and T28 (both) Intervention personalised: yes ‐ personalised because medication specific
Outcomes	Timing of outcome assessment: baseline (200 days before T0) and 28 weeks (T0 = T28 = 196 days) Medication adherence (objective) : medication possession ratio (MPR) ‐ calculated by dividing the days supply of a medication dispensed by the number of days in the time interval of interest Knowledge about medicines (objective): knowledge of medicines and daily use ‐ phone questionnaire; 58 questions ‐ included assessing knowledge Adverse clinical health outcomes (subjective): GP/Hospital visits: self‐reported patient's unplanned visits at the general practitioner or hospital
Notes	Trial registration: NCT01739816 Consumer involvement: unclear ‐ the PMC (polymedication check) is standardised so potential consumers can be involved in the original development of the Swiss PMC Funding source: investigator initiated project; funded in part by Swiss Pharmacists Association, pharmaSuisse Dropout: 18 withdrew, 60 were lost to follow‐up
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Patients were assigned by 2 × 4 block randomisation to intervention or control group. Initially, each study pharmacist received 2 blocks containing 8 dossiers (4 intervention and 4 control), each packed in sealed and unlabelled envelopes. Unclear if envelopes opaque
Allocation concealment (selection bias)	Unclear risk	Once the first patient had consented, the study pharmacist opened 1 envelope out of the first block to reveal which arm of the study the patient had been randomised to. Once all 8 envelopes of block No. 1 had been assigned, the next block was used. Upon request, further blocks were available. Pharmacist would know allocation of some (e.g. if already opened 4 intervention, then would know remaining were control)
Blinding of participants and personnel (performance bias) All outcomes	High risk	Unable to blind; Hawthorne effect
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Patients filled out questionnaire, sealed in envelope, and returned to pharmacy. Interviewers blinded to intervention and without knowledge of the content of the PMC or the patient questionnaire at T0
Incomplete outcome data (attrition bias) All outcomes	High risk	Table 2 summarises reasons for dropout: 34 lost because pharmacist revoked study participation because underestimated time commitment. Missing patients from both T0 and T28 analyses unexplained
Selective reporting (reporting bias)	High risk	MPR for antiplatelets and PPI listed, not mentioned in methods; no results presented for medication knowledge
Other bias	Unclear risk	Sample size calculation: 780 at T0 and 252 at T28 (not reached for adherence). Also study pharmacists received compensation for delivery of each complete patient data set, and patients paid for time spent on telephones