The ENRICHD Social Support Instrument is a valid and reliable tool for measuring social support in coronary artery disease patients, which can be valuable for controlling patient variability in outcomes studies.
The ESSI appears to be a valid and reliable measure of social support in patients undergoing treatment for coronary artery disease. It may prove to be a valuable method of controlling for patient variability in outcomes studies where the outcomes are related to patients' social support.
Vaglio et al. (2004) studied this question.