Table 3. Success Factors in 5 Major Health Impact Assessment (HIA) Impact Evaluation Reports, United States, Europe, Australia, and New Zealand, 2006–2015.

Author and Year of Publication	Success Factors
Davenport et al 2006 (32)	Role of decision makers Involvement of decision makers/key stakeholders in the planning and conduct of the HIA (for example, commissioning, steering group, formulation of recommendations) Input from professionals outside of the usual range of people involved in the decision-making process Balance between decision maker ownership and HIA credibility Policy making process and environment Clear commitment to HIA within organizational decision-making structure Not being a controversial issue Policy support for HIAs (including supporting legislation, promotion of consistency of methods, monitoring, and evaluation) Provision of an enabling structure for HIA (manpower, evidence base, and intersectoral working) Existing statutory frameworks supporting the use of HIAs Recommendations chime with other political drivers Recommendations realistic and can be incorporated into the existing planning process Timing of HIAs Timing of assessment should fit with the decision-making process HIAs need to fit with decision makers’ rules, procedures, and time frames HIA methods Use of a consistent methodological approach Consideration of a broad range of factors that can have an impact on community health and safety Inclusion of empirical evidence relating the effects of a policy, program, or project on health Quantification of impacts Conduct by expert assessors (credibility of results) Methods of reporting HIAs Tailored presentation of information Use insight into organizational concerns and priorities to shape recommendations
Wismar et al, 2007 (35)	Capacity to deal with community pressure Timing in relation to the decision-making process Involvement of organizations that can support conduct of the HIA Culture of public health in the country Political leadership Public support Involvement in early stage of proposal development Legal backup for using health determinants in assessment Creation of health systems units to support HIA Clarification of who bears costs of HIA
Rhodus et al, 2013 (34)	HIA best practices listed as Adherence to minimum elements of HIA as defined by Bhatia et al (37) or to National Research Council (3) criteria Use of HIA as a tool for environmental impact assessment Promotion of health equity Documentation of screening and scoping Rules of engagement memos Communication plans Stakeholder involvement Transparent documentation of literature searches/reviews Use of best available qualitative and quantitative data Evaluation of quality of evidence Identification of data gaps Use of existing tools, metrics, methods, and standards Adaptation of existing tools and methods Detailed documentation of data and methods Use of geographic information systems Use of impact pathways and logic frameworks Clear summary of impact assessments Confidence estimates and assessments of uncertainty Documentation of process for prioritizing recommendations Recommendations that meet established feasibility criteria Development of an implementation plan for recommendations Clear and transparent HIA reporting Process evaluation Establishment of monitoring plans for impact and outcome evaluation
Haigh et al, 2015 (33); Haigh et al, 2013 (36)	Use of a structured stepwise process Flexibility to adapt process to local context Use of evidence to support recommendations Capacity and experience among practitioners and stakeholders Involvement of decision makers and others who can influence decisions or implement recommendations High-quality relationships across sectors Engagement of community stakeholders Shared goals and values among HIA participants Use of “proactive positioning” to achieve optimal timing Flexibility in time and timeliness to conduct HIA
Bourcier et al, 2015 (31)	Method of screening and choosing HIA targets wisely because an HIA is not always the right tool Investment in the right team to conduct HIA Engagement of key stakeholders Engagement of decision makers throughout the process Development of clearly articulated recommendations that spark action Delivery of compelling messages to the right audiences at the right times Use of approach to take advantage of HIA credibility