Recruitment and adherence of randomized controlled trials for mild cognitive impairment: A systematic review and meta‐analysis

Abstract

Objectives The recruitment and adherence status of randomized controlled trials (RCTs) for population with mild cognitive impairment (MCI) are little known. We aimed to explore the RCT recruitment and adherence status and factors associated with these among MCI patients. Methods We searched MEDLINE, EMBASE, Cochrane Library, CINAHL, PsycINFO, and PsycARTICLES from inception to 8th July 2019. Included studies were RCTs conducted among MCI patients with available data of invitation rate, eligibility rate, randomization rate, recruitment rate, adherence rate, satisfaction rate, or potential barrier for recruitment and compliance. Two authors screened the studies and extracted the data independently. We calculated pooled proportions of each rate and their 95% confidence intervals (CIs) using random‐effects meta‐analysis. Meta‐regression and subgroup analysis was conducted. Results Hundred and ten articles were judged to meet the study inclusion criteria from 10 387 articles. The invitation rates ranged from 9% to96% but were not pooled together due to high heterogeneity. The pooled overall eligibility, randomization, recruitment, intervention adherence, and follow‐up adherence rates were 55% (95% CI: 48%‐62%), 86% (95% CI: 81%‐91%), 44% (95% CI: 37%‐50%), 88% (95% CI: 86%‐90%), and 85% (95% CI: 83%‐87%), respectively. Non‐MCI (47.5%), disease or medical problems (13.8%), and loss of interest (8.5%) were the most frequent reasons for screen failure. Refusal without reason (36.6%), adverse events (30.9%), and health issues (7.7%) were the most frequent reasons for drop‐out. Conclusions This study provided important information for future RCTs targeting at MCI patients. Strategies designed to improve participant recruitment and RCT adherence should be developed among this population.

Comparative Effectiveness of Interventions for Global Cognition in Patients With Mild Cognitive Impairment: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

“…The acceptability of the included interventions should also be taken into account. In a recent meta-analysis about the recruitment rate and adherence rate among MCI patients, the pooled intervention adherence rate for all types of interventions ranged from 82 to 96% (Xu et al, 2020). Transcranial magnetic stimulation, lifestyle modification/counseling, and dietary intervention had the top three intervention adherence rates of more than 90% in this study.…”

Audit of screen failure in 15 randomised studies from a low and middle-income country

“…Declining to participate in the trial (22.2%) and non-compliance (2.2%) made up a big part of screen failure. These are especially important determinants as they seem most amenable to correction [ 8 , 9 ]. To an extent, non-compliance of patients and also their decision against participating in the trial can benefit from better counselling and teaching methods by investigators involved in recruitment.…”

Optimizing the physical activity intervention for older adults with mild cognitive impairment: a factorial randomized trial

“…According to the SCT and previous studies, a total of two core intervention components (PA material and PA education) and three implementation strategies (role modeling, reminding, and goal-setting) ( 14 , 19 ) were selected. The hypothesized conceptual model based on SCT is shown in Figure 1 .…”

“…Older adults in this group received text messages that reminded them to perform PA. Reminding could increase the awareness of participants to perform PA ( 14 ). The frequency, order, repetition, timing, and direction of text messages were determined based on the participants' preferences and the WHO guidelines ( 23 ).…”

“…Several implementation strategies have been identified to increase the PA level in older adults with cognitive decline, but there is no consistent approach to the type of strategies being used. A recent systematic review has demonstrated that several implementation strategies, such as role modeling, goal-setting, and reminding, have proven effective in improving the PA level of participants ( 14 ). One RCT utilized text messages to remind participants aged 55–70 years to exercise and found that those who received reminders exercised 1.21 times as much as the control group ( 15 ).…”