title: What makes health impact assessments successful? Factors contributing to effectiveness in Australia and New Zealand.
abstract: BACKGROUND
  While many guidelines explain how to conduct Health Impact Assessments (HIAs), less is known about the factors that determine the extent to which HIAs affect health considerations in the decision making process. We investigated which factors are associated with increased or reduced effectiveness of HIAs in changing decisions and in the implementation of policies, programs or projects. This study builds on and tests the Harris and Harris-Roxas' conceptual framework for evaluating HIA effectiveness, which emphasises context, process and output as key domains.
  
  
  METHODS
  We reviewed 55 HIA reports in Australia and New Zealand from 2005 to 2009 and conducted surveys and interviews for 48 of these HIAs. Eleven detailed case studies were undertaken using document review and stakeholder interviews. Case study participants were selected through purposeful and snowball sampling. The data were analysed by thematic content analysis. Findings were synthesised and mapped against the conceptual framework. A stakeholder forum was utilised to test face validity and practical adequacy of the findings.
  
  
  RESULTS
  We found that some features of HIA are essential, such as the stepwise but flexible process, and evidence based approach. Non-essential features that can enhance the impact of HIAs include capacity and experience; 'right person right level'; involvement of decision-makers and communities; and relationships and partnerships. There are contextual factors outside of HIA such as fit with planning and decision making context, broader global context and unanticipated events, and shared values and goals that may influence a HIA. Crosscutting factors include proactive positioning, and time and timeliness. These all operate within complex open systems, involving multiple decision-makers, levels of decision-making, and points of influence. The Harris and Harris-Roxas framework was generally supported.
  
  
  CONCLUSIONS
  We have confirmed previously identified factors influencing effectiveness of HIA and identified new factors such as proactive positioning. Our findings challenge some presumptions about 'right' timing for HIA and the rationality and linearity of decision-making processes. The influence of right timing on decision making needs to be seen within the context of other factors such as proactive positioning. This research can help HIA practitioners and researchers understand and identify what can be enhanced within the HIA process. Practitioners can adapt the flexible HIA process to accommodate the external contextual factors identified in this report.
authors.affiliation: Centre for Health Equity Training, Research and Evaluation CHETRE, Ingham Institute, University of New South Wales, Sydney, 2052, Australia. f.haigh@unsw.edu.au.
authors.forename: Fiona
authors.initials: F
authors.lastname: Haigh
authors.affiliation: Centre for Primary Health Care and Equity, University of New South Wales, Sydney, 2052, Australia. e.harris@unsw.edu.au.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Harris
authors.affiliation: Centre for Primary Health Care and Equity, University of New South Wales, Sydney, 2052, Australia. b.harris-roxas@unsw.edu.au.
authors.forename: Ben
authors.initials: B
authors.lastname: Harris-Roxas
authors.affiliation: Southgate Institute for Health, Society & Equity, Flinders University, Adelaide, Australia. fran.baum@flinders.edu.au.
authors.forename: Fran
authors.initials: F
authors.lastname: Baum
authors.affiliation: University of Washington School of Public Health, Seattle, USA. adannen@uw.edu.
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Dannenberg
authors.affiliation: Centre for Primary Health Care and Equity, University of New South Wales, Sydney, 2052, Australia. m.f.harris@unsw.edu.au.
authors.forename: Mark F
authors.initials: MF
authors.lastname: Harris
authors.affiliation: School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia. helen.keleher@monash.edu.
authors.forename: Helen
authors.initials: H
authors.lastname: Keleher
authors.affiliation: Centre for Health Equity Training, Research and Evaluation CHETRE, Ingham Institute, University of New South Wales, Sydney, 2052, Australia. l.kemp@unsw.edu.au.
authors.forename: Lynn
authors.initials: L
authors.lastname: Kemp
authors.affiliation: Centre for Impact Assessment Research and Training (CIART), Department of Geography, University of Otago, Dunedin, New Zealand. rkm@geography.otago.ac.nz.
authors.forename: Richard
authors.initials: R
authors.lastname: Morgan
authors.affiliation: Centre for Health Equity Training, Research and Evaluation CHETRE, Ingham Institute, University of New South Wales, Sydney, 2052, Australia. h.ngchok@unsw.edu.au.
authors.forename: Harrison
authors.initials: H
authors.lastname: Ng Chok
authors.affiliation: WHO Collaborating Centre in Environmental Health Impact Assessment and School of Public Health, Curtin University, Bentley, Australia. J.Spickett@curtin.edu.au.
authors.forename: Jeff
authors.initials: J
authors.lastname: Spickett
mesh_terms: D001315:Australia; D003657:Decision Making; D062489:Health Impact Assessment / Q000379:methods*; D006801:Humans; D009520:New Zealand; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires