Kirchhoff’s diffraction theory is introduced as a new case study in the realism debate. The theory is extremely successful despite being both inconsistent and not even approximately true. Some habitual realist proclamations simply cannot be maintained in the face of Kirchhoff’s theory, as the realist is forced to acknowledge that theoretical success can in some circumstances be explained in ter...

Background Childhood vaccination coverage rates in low- and middle-income countries (LMICs) vary significantly, with some countries achieving higher rates than others. Several attempts have been made in Nigeria to achieve universal vaccination coverage but with limited success. This study aimed to analyse strategies used to improve ...

Pawson and Tilley’s Realistic Evaluation was published twenty years ago. It is timely to reflect on its origins and future directions. The basic ideas for Realistic Evaluation were first aired publicly at a criminology conference in San Francisco in 1991. There followed a series of papers in which the ideas were refined. Once Realistic Evaluation appeared in 1997 we wrote a few more papers toge...

BACKGROUND The idea that underlying, generative mechanisms give rise to causal regularities has become a guiding principle across many social and natural science disciplines. A specific form of this enquiry, realist evaluation is gaining momentum in the evaluation of complex social interventions. It focuses on 'what works, how, in which conditions and for whom' using context, mechanism and outc...

Increasing policy demand for realist evaluations of research and capacity-building programmes reflects a recognition of the management, governance and impact gains that can result from evaluation. However, the evidence base on how to successfully implement realist evaluations of complex interventions in international development efforts is scarce. We know little about the associated merits, lim...

A framework for spatio-temporal reasoning has to account for the variety of modes of existence and persistence in time. It should thus be based on a formal ontology of spatiotemporal reality. For pragmatic reasons, however, it is even better if while being based on a realist foundation, the framework has the potential of being extended and amended contextually. I propose a rich modular framewor...

Increasing policy demand for realist evaluations of research and capacity-building programmes reflects a recognition of the management, governance and impact gains that can result from evaluation. However, the evidence base on how to successfully implement realist evaluations of complex interventions in international development efforts is scarce. We know little about the associated merits, lim...