I am working on a similar research question of yours and I have so far discovered that it depends. Cost effectiveness as a concept requires 1) accounting cost and 2) well defined objective (impact, product etc.) So if you want to study cost effectiveness I would first look for available data on these two aspects and then specify the question further.
My work is in innovation systems and the cost effectiveness depends a lot on how many organizations (the objective) were reached by participatory action research. Here is a a brief info about the measurement system I developed for measuring cost effectiveness on agricultural research for development interventions using participatory research.
Poster Learning System for Agricultural Research for Development (L...
Good answer from Murat - it really does depend on many factors i.e. the amount of stakeholders, participants, co-reseachers etc - as well as how longitudinal the study is and to what extent it wants to develop and/or re-orientate services, organisations or communities. I've attached a few items that may assist.The book chapter is mixed methods - but focuses on action research - and you may find the strengths and limitations sections of particular use in planning. The other attached article reports a two-year PAR project in a UK NHS Trust osteoporosis service. Very little funding was needed - as all the stakeholders, participants and co-reserachers were recruited from willing 'volunteers'. The service developments and reorientation occurred 'naturally' as there was a collective will already to restructure the service and 'other' stakeholders willingly came on board when they started to hear about the project as it evolved further.
Much depends on the scope, size, and research design (and what is available from the granting agency). In my previous health research, published in Environmental Justice 2013, (and in Local Environment in 2016), the costs were minimal (tiny incentives to complete f2f interviews, N=100 households, with a very high % response rate). I added a small stipend for the community partner for all their time/labor, but they would have done it pro bono (because, perhaps, of my many years of pro bono leadership IN the community organization). So the process was not totally measurable in cost/dollar terms. And of course I shared findings with the community after the analysis was done. Reciprocity makes the world go around.
I like Kathleen's take on this. Often, PAR is a 'gamble' for funding agencies - due to its longitudinal nature and unknown outcomes. This often means that researchers who adopt PAR are looking for a lot of voluntary 'goodwill' to implement and complete their projects. I agree that reciprocity is very important. We reap what we sow!!
Good information from Murat. Will be very useful for me. I was always skeptical about the ability to study the cost effectiveness of such programs, and thought they often were unnecessary expenditure & meant mainly to facilitate donor agency staff visits.