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This paper discusses recent trends in the use of replications in economics. We include the results of recent replication studies that have attempted to identify replication rates within the discipline. These studies generally find that replication rates are relatively low. We then consider obstacles to undertaking replication studies and highlight replication initiatives in psychology and political science, behind which economics appears to lag

(2012) Assessing 'what works' in international development: metaanalysis for sophisticated dummies, Journal of Development Effectiveness, 4:3, 456-471, DOI: 10.1080/19439342.2012 Many studies of development interventions are individually unable to provide convincing conclusions because of low statistical significance, small size, limited geographical purview and so forth. Systematic reviews and meta-analysis are forms of research synthesis that combine studies of adequate methodological quality to produce more convincing conclusions. In the social sciences, study designs, types of analysis and methodological quality vary tremendously. Combining these studies for meta-analysis entails more demanding risk of bias assessments to ensure that only studies with largely appropriate methodological characteristics are included, and sensitivity analysis should be performed. In this article, we discuss assessing risk of bias and meta-analysis using such diverse studies.

The concentration of flavanols in fresh apical shoots of tea was highest during the cold season. Shoots plucked during slow growth conditions contained a higher proportion of simple catechins to catechin gallates, (-)-epigallocatechin being most significantly affected. The predominant effect of nitrogen fertiliser was to depress the concentration of (-)-epigallocatechin in the shoot. The significance of these findings with respect to tea quality is discussed.

Systematic reviews and meta-analysis have risen in popularity in international development to provide evidence on 'what works'. This paper reports the findings of a meta-analysis to assess the impact of microcredit on women's control over household spending to illustrate the challenges of conducting meta-analysis in the case of a diverse evidence base. We provide an assessment of methodological quality and present the findings of a meta-analysis. The results suggest that the effect sizes are small. Furthermore, the confidence that we can place in these findings is limited by the high level of heterogeneity within and between studies and the general reliance on nonexperimental studies and statistical analyses which are not reported in sufficient detail to enable confident judgement as to their robustness.