Tree diagram of hierarchical agglomerative cluster analysis of the six health-related behaviours. The dendrogram provides a visual presentation of the distance at which clusters are combined. It is read from left to right and the vertical lines show joined clusters. The position of the vertical line on the scale indicates the distance at which clusters are joined. Variables with smaller distance have higher homogeneity and they are combined with a vertical line linking them in a cluster, while the variables with larger distance indicate the least homogenous clusters. The distances (agglomeration coefficients) displayed in the top of the plot are rescaled (by default) to fall into a range of 1 to 25.