29 studies that met the eligibility criteria (ie, economic evaluations, cluster-randomised trials, non-randomised trials, controlled before-and-after studies, and interrupted time-series studies exploring the effective of these interventions) were categorised according to intervention type: multimodal, care bundles, policies, and surveillance, monitoring, and feedback.
Because non-equivalent comparison groups may distort the results of evaluations, cluster-randomized trials (in which healthcare professionals or groups of professionals, rather than patients are randomized) are more likely to provide valid results than other research designs, such as controlled before-after or time-series studies [ 43].
Although several entities have derived slightly lower values (i.e., 0.2, 0.1, and 0.08 ppm), it is clear that with most comprehensive evaluations clustering at 0.3 ppm that a formaldehyde level of 0.1 ppm as derived and justified in the present review represents a conservative and health-protective concentration for indoor air in residential dwellings.
A multifactorial evaluation (cluster randomized, n = 981) was carried out between 1998 and 2000.
In health care service evaluation cluster RCTs, pre-specifying the numbers of clusters available, are frequently used.
All grant materials were collated from the Global Fund internal database, with the consent of the Strategy, Performance, and Evaluation Cluster at the Global Fund.
In external evaluation, clustering results are evaluated based on the known class labels.
For the sake of convenience, the evaluation clustered activities within a life-cycle approach.
Clustering of costs and of outcomes is often neglected in economic evaluations alongside cluster randomized trials that have individual cost data.
Several economic evaluations alongside cluster randomized trials have used bootstrapping to deal with asymmetrically distributed costs [ 10- 12], but without specifying whether they sampled individuals or clusters.
Incorporation of economic evaluations within (cluster) randomised controlled trials of public health interventions has been a growing trend in the past decade [ 13, 14].
