Of the 750 women searched during the pilot study, 507 were eligible (e.g., community-dwelling, aged 65 89 years and alive based on a vital statistics linkage completed in August 2002) for the new study to begin recruitment in 2003.
These data were linked so that we could conduct a case controlled, before and after study of hospital utilisation of people referred to IAPT, and by the time that permissions were obtained and this linkage completed, the IAPT evaluation programme was well underway.
Linkage was completed using probabilistic linkage software.
Ferreira and Hitchcock [20] compared the performance of four major hierarchical methods (single linkage, complete linkage, average linkage and Ward's method) for clustering functional data.
Blashfield [16] compared four types of hierarchical clustering methods (single linkage, complete linkage, average linkage and Ward's method) for accuracy in recovery of original population clusters.
Hands and Everitt [18] compared five hierarchical clustering techniques (single linkage, complete linkage, average, centroid, and Ward's method) on multivariate binary data.
Kuiper and Fisher [15] compared six hierarchical clustering procedures (single linkage, complete linkage, median, average linkage, centroid and Ward's method) for multivariate normal data, assuming that the true number of clusters was known.
Hierarchical clustering technique (e.g. Ward method, single linkage, complete linkage, etc)., K means and latent class clustering (LCC) have been used in road accident analysis [2, 3, 20 22].
After selection, we found five usable clustering methods: Average linkage, complete or longest distance method, flexible-beta method, McQuitty's similarity method, and Ward's minimum-variance method.
The cluster analyses using the single linkage, complete linkage, and average linkage methods did not produce clinically interpretable results.
Average linkage, complete linkage, single linkage, neighbor joining [ 120] and UPGMA [ 121] are the most widely used methods.
