5.1. The Importance of Evidence

Evidence has been central to the development of Housing First. It is through the collection of good quality evidence that Housing First became influential in homelessness policy debates in North America and was able to attract and then sustain funding. In Europe, the emerging evidence base for Housing First has shown that it can work in a diverse range of countries, which have significant differences in their welfare systems, housing systems, culture and levels of economic prosperity. As is shown in the Appendix, Housing First evaluations are reporting successes in countries as diverse as Denmark, England, France, the Netherlands, Portugal, Scotland and Spain.

There are several benefits to evaluating Housing First services:

• Strong evidence has been fundamentally important in persuading governments, charities and homelessness service providers to consider using Housing First. Federal government in the USA regards Housing First as a service model of proven effectiveness((Tsemberis, S. (2010) Housing First: The Pathways Model to End Homelessness for People with Mental Illness and Addiction Minnesota: Hazelden.)) and systematic evaluations have led to Housing First becoming central to the Canadian and French homelessness strategies. Evaluation has been crucial to promoting the idea of Housing First, in demonstrating that Housing First works and in showing that Housing First can be cost-effective. However, evaluations of Housing First must be of good quality and should ideally contrast the Housing First approach with existing services, if the evidence is to be persuasive.
• Measuring outcomes systematically and carefully allows a Housing First service to assess how well it is performing. Good quality evaluation allows Housing First services to learn about any limitations in their support or housing provision, enabling improvements to be made.
• Evaluation showing good performance can help Housing First services ensure they have funding in place and help make the case for Housing First services to be expanded.
• Evaluating Housing First is the main means by which good practice and important lessons about providing Housing First can be learned. Conducting and sharing evaluations can be very useful for everyone involved in developing and providing Housing First services.

Evaluation presents risks as well as opportunities. Attention must be paid to how information on performance is collected, because an evaluation that is not well designed or properly conducted can undermine the case for an individual Housing First service and Housing First in general. Anyone undertaking an evaluation of Housing First needs to be clear that the evaluation, if it is properly conducted, will not report that a Housing First service is perfect. There will be at least some minor issues that need addressing and, while the rates at which Housing First will end homelessness are, on current evidence, usually very high compared to most other homelessness services, Housing First will not work well for absolutely everyone in all circumstances.

Evidence can certainly help support Housing First, indeed it can be crucial to ensuring that the idea is promoted and that Housing First services are sustainably funded. The use of good quality evidence has been fundamental to successfully promoting Housing First in North America. However, collecting evidence does present some risks because it can highlight limitations as well as successes. It is also important to note that while philanthropists, charities and governments will not expect Housing First to report perfect results, they may not always be persuaded by evidence, even if a Housing First service is very successful.