The following characteristics of the population, intervention, and methodological quality of the trials were defined a priori as potential effect modifiers: sex, dose of aspirin, duration of treatment, allocation concealment, and compliance with treatment.
We plan to use the random effects model rather than the fixed effects model, because we assume that the included studies will not be functionally equivalent and will show considerable clinical (concerning population, intervention) and methodological (design, quality etc).
We plan to use a random effects model rather than fixed effects one, because we assume that the included studies will not be functionally equivalent and will show considerable clinical (concerning population, intervention) and methodological (design, quality etc).
A standardised data extraction recorded information on study context, population, interventions, outcomes and methodological quality.
Pooling results in a meta-analysis implicitly assumes that the studies are sufficiently similar with respect to their populations, study interventions, outcomes, and methodological quality that one could reasonably expect a comparable underlying treatment effect.
Forming accurate conclusions about the impact of person-centered interventions on residents and staff is hampered by the heterogeneity of the interventions and significant methodological differences between studies.
The aim of this paper is to describe the design of the U-PROFIT trial, the content of the two interventions and its methodological challenges.
The problem thus lies with the recognition of heterogeneity in a trial, which includes clinical heterogeneity (variability in the participants, interventions and outcomes), methodological heterogeneity (variability in trial design and quality) and statistical heterogeneity (variability in the treatment effects evaluated in different trials).
Two reviewers extracted data on population, intervention, outcome and methodological quality.
