Table 1.

Information about the various variables extracted for the overview of chronic disease models

Study year	Information was recorded on the number of studies that were published during the various years from 2003-2011
Study location	Information was recorded on the location of the studies including U.S. versus non U.S. based and whether or not the studies were done in rural or urban settings.
Study design	Information was also recorded if the studies were observational or randomized controlled clinical trials and if they were interventional or not.
Studies follow up	The duration of the studies was also recorded to examine the impact of the chronic models on longitudinal
Disease studied	The review is focused on diseases including Diabetes, Chronic Obstructive Pulmonary Disease and Cardiovascular diseases because of their predominance in resulting death and disability worldwide.
Chronic disease model and its elements	Information was recorded on the specific chronic disease models and their elements that were described and evaluated across all these studies
Outcomes assessed	Information was also recorded about the various outcomes that were measured in these studies.