Unfortunately there has been a bug in the TSA program when calculating the required information size for continuous outcomes and we have now published a new amended version. In the former version the required information size was calculated twice as large as it should be in a fixed- as well as in a random-effects TSA. We apologize for the inconvenience this may cause and urge you to download the new version from the TSA homepage and redo your analyses.

The required information size for dichotomous outcomes has been calculated correct in the old version so there is no need to re-analyse dichotomous meta-analyses.

Trial sequential analysis (TSA) is a user-friendly software application which makes it easy for authors of systematic reviews and meta-analysis to apply a number of advanced sequential hypothesis testing techniques to their meta-analyses. TSA is free of charge. It is a Java-based software application which means that it runs on all operating systems that support Java (Windows, Mac OS, Linux and more), and it comes with a comprehensive manual suitable for systematic review authors with various levels of statistical background knowledge.

TSA is accompanied by the data converter application RM5 Converter. This application allows systematic review authors to convert their Review Manager v.5 meta-analysis to a format which can be read by the TSA application. RM5 Converter is also free of charge and Java-based. Instructions for the use of the RM5 Converter are provided in the accompanying manual.

TSA and RM5 Converter are distributed by the Copenhagen Trial Unit, Center for Clinical Intervention Research, Rigshospitalet, Copenhagen, Denmark.