List of metropolitan areas by population. One concept which measures the world's largest cities is that of the metropolitan area, which is based on the concept of a labor market area and is typically defined as an employment core (an area with a high density of available jobs) and the surrounding areas that have strong commuting ties to the core.
Average Costs. In treatment year 1, the average costs per patient diagnosed with PTSD ($8,300), TBI ($11,700), or both ($13,800) were much higher than the average costs for those with neither PTSD nor TBI ($2,400) (see Table 2 and Figure 3 on page 20).
1 Rand.org, meanwhile, put the estimated two-year cost of PTSD treatment around $5,900 to $10,300. 2  The number of patients referred to by CBO in the PTSD treatment alone was 103,500, while those who were treated for both PTSD and TBI were 26,600 patients.