Lessons learnt during a complex, multicentre cluster randomised controlled trial: the ProAct65+ trial.

Area of Science:

• Gerontology
• Clinical Trials
• Exercise Science

Background:

• Randomized controlled trials (RCTs) often face recruitment and retention challenges.
• Intervention fidelity and data accuracy are critical for reliable results.
• The ProAct65+ cluster RCT addressed these issues in an exercise study for adults aged 65+.

Purpose of the Study:

• To describe methods used to overcome challenges in a cluster randomized controlled trial (RCT) involving exercise interventions for older adults.
• To detail strategies for improving participant recruitment, retention, intervention fidelity, and adverse event capture.

Main Methods:

• Extended recruitment periods and increased participant invitations to address organizational delays.
• Introduced telephone pre-screening to identify and exclude ineligible participants.
• Implemented quality assurance observations by experienced instructors to maintain intervention fidelity.
• Utilized diaries for data collection on falls and costs, adjusting frequency to improve completion.

Main Results:

• Organizational factors, such as room availability, impacted recruitment timelines.
• Telephone pre-screening effectively excluded highly active individuals and frequent fallers.
• Recruiting volunteer peer mentors proved difficult; their caseload was lower than anticipated.
• Quality assurance observations enhanced fidelity to the group exercise intervention.
• Diary completion was variable, leading to reduced data collection frequency.
• Standardizing adverse event classification required joint assessment across research sites.

Conclusions:

• General practice recruitment for trials may require longer periods due to organizational constraints.
• Targeted screening can optimize participant selection for exercise interventions.
• Peer mentor recruitment and feasibility require separate investigation.
• Tailored exercise programs necessitate quality assurance for fidelity, and risk assessment standardization is crucial.
• Adjusting data collection methods, like diary frequency, can mitigate participant burden and improve data completeness.