Robustness and external validity: what do we learn from repeated study design over time?
with Andrew Dillon, Jed Friedman. Working paper

Recruitment, effort and retention effect of performance contracts for civil servants. Experimental evidence from Rwandan primary schools.
American Economic Review, Vol 111. No 7, July 2021, with Clare Leaver, Owen Ozier, Andrew Zeitlin, available from arXiv ; previous versions appeared as RISE Working Paper 20/048,  IZA Discussion Paper 13696, Word Bank Policy Research Working Paper 9395, CEPR Discussion paper 15333.  See VoxDev, Selection and incentive effects of teacher performance contracts in Rwanda  

Health information, treatment, and worker productivity.
Journal of the European Economic Association, Vol 19, Issue 2, April 2021, with Andrew Dillon, Jed Friedman

Productivity and health: alternative productivity measures using physical activity. 
World Bank Economic Review, Vol 35, Issue 3, October 2021,p 652-680,with Oladele Akogun, Andrew Dillon, Jed Friedman, Ashesh Prasann 

Diabetes, employment and behavioural risk factors in China: Marginal structural models and fixed effects estimation.
Economics and Human Biology, Vol 39, December 2020, with Till Seuring, Marc Suhrcke, Max Bachmann, available as IZA Discussion Paper 11817

Do returns to education depend on how and who you ask?
Economics of Education Review, Vol.60, Oct 2017, 5-17, with Kathleen Beegle, Andrew Dillon

What explains the variation in child labor statistics? Evidence from a survey experiment in Tanzania,
Journal of Development Economics, 98(1):136-147, 2012, with Andrew Dillon, Elena Bardasi, Kathleen Beegle

Do labor statistics depend on how and to whom the question was asked?  Results from a randomized survey experiment,
World Bank Economic Review, 25 (3):418-447, 2012, with Elena Bardasi, Kathleen Beegle, Andrew Dillon

Understanding health worker issues: a selective guide to the use of qualitative methods,
2009, in Mario Dal Poz and Agnes Soucat, Handbook on Monitoring and Evaluating Health Workforce, WHO and World Bank, with Tomas Lievens, Magnus Lindelow

Qualitative research to inform quantitative analysis: Health workers’ absenteeism in two countries,
in Sami Amin, Jishnu Das and Markus Goldstein, 2008, Are You Being Served? New Tools for Measuring Service Delivery, The World Bank, with Magnus Lindelow, Tomas Lievens