|Equation||(# participants) x (% participants getting supportive housing solely because of the program) x (% decrease in hospitalizations due to program) x (% participants hospitalized as a result of a physical illness) x (QALY increase) x ($QALY)|
|Explanation||This metric estimates the impact of avoided or reduced homelessness on the rate of hospitalization, estimated in quality-adjusted life years (QALY).
Number of participants: Reported by program.
Percent of these adults who avoid homelessness due the program: [0.52], for programs serving individuals at imminent risk of homelessness (e.g. individuals coming from shelters, or with eviction notices and no feasible housing alternative), we assume a 100% rate of effectiveness. To this number, we subtract the percentage of homeless individuals in the Twin Cities metropolitan area who are on a waiting list for any public housing, Section 8 housing, or some other type of housing that offers financial assistance as a counterfactual [48%] (Wilder Research, 2016).
Percentage of decrease in hospitalizations due to program: [0.30], based on Culhane, Metreaux & Hadley (2001); Martinez & Burt (2006); and Sadowski, Kee, VanderWeele & Buchanan (2009)
Percentage of patients hospitalized as a result of physical illness: [0.20], for those who are housed in supportive housing and who avoided hospitalization or would have been hospitalized due to some general diagnosis, based on the findings of Salit, Kuhn, Hartz, Vu & Mosso (1998).
QALY increase: [0.025], estimate for the value of avoiding hospitalization due to general illness (Lavelle, Meltzer, Gebremarian, Lamarand, Fiore & Prosser, 2011).
$ value per QALY: [$50,000].
Benefits are then discounted to present value based on the average age of participation to life expectancy.
|References||Culhane, D. P., Metreaux, S. & Hadley, T. (2001). The impact of supportive housing for homeless people with severe mental illness on the utilization of the public health, correcting, and emergency shelter systems: The New York-New York Initiative. Washington, DC: Fannie Mae Foundation. Retrieved from https://www.researchgate.net/publication/228638508_The_Impact_of_Supportive_
Lavelle, T.A., Meltzer, M. I., Gebremariam, A., Lamarand, K., Fiore, A.E. & Prosser, L.A. (2011). Community-based values for 2009 pandemic influenza A H1N1 illnesses and vaccination-related adverse events. PLoS One, 6(12). E27777.
Martinez, T. E. & Burt, M. (2006). Impact of permanent supportive housing on the use of acute care health services by homeless adults. Psychiatric Services: A Journal of the American Psychiatric Association, 57(7), 992-999.
Sadowski, L., Kee, R., VanderWeele, T. & Buchanan, D. (2009). Effect of a housing and case management program on emergency department visits and hospitalizations among chronically ill homeless adults: A randomized trial. Journal of the American Medical Association, 301(17), 1771-1778.
Salit, S., Kuhn, E., Hartz, A., Vu, J. & Mosso, A. (1998). Hospitalization costs associated with homelessness in New York City. New England Journal of Medicine, 338(24), 1734-1740.
Wilder Research. (2016). 2015 homeless adults and children: Minnesota statewide survey data. Retrieved from http://mnhomeless.org/minnesota-homeless-study/detailed-data-interviews/2015/HennepinCountyMN_Adult2015_Tables51-67.pdf