Please look for work by Abhijit Banerjee & the Duflo sisters, mainly done with IFMR in India. Attached one of the papers. Should be easy to find on the internet.
Midgley, N., Ansaldo, F., & Target, M. (2014). The meaningful assessment of therapy outcomes: Incorporating a qualitative study into a randomized controlled trial evaluating the treatment of adolescent depression. Psychotherapy, 51(1), 128.
O'Cathain, A., Thomas, K. J., Drabble, S. J., Rudolph, A., Goode, J., & Hewison, J. (2014). Maximising the value of combining qualitative research and randomised controlled trials in health research: the QUAlitative Research in Trials (QUART) study--a mixed methods study. Health Technology Assessment, 18(38).