The Delphi Method
The Delphi Method is a survey technique that began during the 1940s as a method to obtain expert forecasts about the future of military technology. The Delphi method utilizes multiple rounds of surveys in order to obtain consensus from a group of individuals deemed experts in a particular field. Common group communication failures can be avoided using this method, such as power dynamics or pressure to conform (Jewell 2011) and it promotes in-depth conversation among your chosen experts. While discussing the technique in our class session, some raised the question, who is considered an “expert”? Is it limited to those with high levels of education or more explicit knowledge? One of the advantages of the Delphi method is that it allows the researcher to define the “experts” and thus permits a consideration of what is most suitable in the context of your research question. Experts in the case of the Delphi method are individuals with extensive knowledge on a topic, and therefore individuals with extensive tacit knowledge could be selected as experts, depending on your question.
In order to practice the technique, I facilitated the formulation of a Delphi method survey of recent MPH graduates (within the past 5 years) in a recent class. Using class input we formulated the following 1st round survey questions:
1. What do you see as the 3 most important emerging trends in public health?
2. What areas of public health do you see as having the greatest job growth potential in the near future?
3. What do you believe to have been the single most important factor in attaining your current position (e.g. personal or professional connections, in-depth knowledge of a field, advanced ability in a skill, etc)?
4. Having now entered the workforce, what skill or area do you regret not having enhanced further during your graduate degree?
Completion of the 1st round allowed for a reflection on the use of the Delphi method more broadly. One interesting issue that emerged in our survey was the reluctance of our chosen “experts” to speculate about the future. In our case, as was raised in class, perhaps a more appropriate group of experts would have been higher level professionals in the field or those more associated with career counseling and forecasting. I imagine such a group would be more comfortable providing their opinion on the future, compared to our respondents who felt this was perhaps beyond their scope of knowledge of the field of public health.
Another important point to consider is whether your question would be better answered using a standard survey. When using the Delphi method, it’s important to remember you are seeking the informed opinion of your respondents. In the case of our survey, a question such as #4 would perhaps be better suited for a standard survey utilizing sampling methods that allowed for generalization to the target population. As was demonstrated in a class example (Milat 2012), this might also take the form of reaching consensus about a shared definition (in the case of our example, “scaling-up”).
Finally, the smaller scale and more selective nature of the Delphi method provide an excellent space for open dialogue around your subject of choice. An interesting issue that emerged from the first round and was not addressed in the survey instrument was our definition of “graduate”. As it turns out, 5 out of 13 participants had not completed their final project although they are working full time and finished their coursework. The multi-phase nature of this method allows for a continued conversation around this topic, something that otherwise might have to be postponed until another phase of research if using a standard survey.
Jewell, A. (2011). The Delphi Technique. Available at: http://delphitechnique.blogspot.ca/2011/02/what-is-delphi-technique_13.html
Milat, A.J. et al. (2012). The concept of scalability: increasing the scale and potential adoption of health promotion interventions into policy and practice. Health Promotion International, 28(3).