> The succession and clustering of interventions that we see in at least four cases (pathway b) does not appear to be an isolated occurrence.
A multilevel Poisson regression model was applied to estimate Incidence Rate Ratios (IRR) with 95% Confidence Intervals (CI) for A/T surgery among children aged 2 9 years in 2004 2006, while taking into account clustering of interventions within the 21 Local Health Units.
A random-intercept Poisson regression model was applied to estimate Incidence Rate Ratios (IRR) with 95% confidence Intervals (CI) for A/T surgery associated with age, sex, and citizenship (Italian and non-Italian), while taking into account clustering of interventions within Local Health Units.
The cluster of intervention, and thus the unit of randomisation, was the commune and its corresponding health station.
After adjusting for clustering, members of intervention households had 15% fewer weeks of diarrhoea than those of control households, but the confidence intervals indicated little statistical support (longitudinal prevalence ratio 0.85, 95%CI: 0.61 to 1.20).
Because of concurrent interventions like these, it is not clear whether the decision support interventions alone or the cluster of interventions were responsible for the effect.
Because the set of interventions were not mutually exclusive, we have not reported on a full set of incremental comparisons for the cluster of interventions relating to cardiovascular disease.
According to the Health Council of The Netherlands, 'preconception care' (henceforth PCC) refers to the large cluster of interventions "aimed at ensuring that couples who wish to have children start a pregnancy under the best possible conditions" [ 1].
Incremental cost effectiveness ratios are also provided for each cluster of interventions, which give the additional cost needed to secure one extra healthy life year as successively less cost effective strategies are entered into the mix.
In trials of complex interventions there is likely to be clustering of the intervention effect within therapists.
A limitation to the design of the trial was the non-random allocation of clusters to intervention and control blocks.
