Mini-review: effect sizes and meta-analysis for antifouling research.

It is widely recognised that findings from experimental studies should be replicated before their conclusions are accepted as definitive. In many research areas, synthesis of results from multiple studies is carried out via systematic review and meta-analysis. Some fields are also moving away from null hypothesis significance testing, which uses p values to identify 'significant' effects, towards an estimation approach concerned with effect sizes and confidence intervals. This review argues that these techniques are underused in biofouling and antifouling (AF) research and discusses potential benefits of their adoption. They enable comparison of test surfaces even when these are not tested simultaneously, and allow results from repeated tests on the same surfaces to be combined. They also enable the use of published data to explore effects of different variables on the functioning of AF surfaces. AF researchers should consider using these approaches and reporting results in ways that facilitate future research syntheses.