TY - JOUR AU - Harden, Markus AU - Friede, Tim PY - 2018 DA - 2018/11/29 TI - Sample size calculation in multi-centre clinical trials JO - BMC Medical Research Methodology SP - 156 VL - 18 IS - 1 AB - Multi-centre randomized controlled clinical trials play an important role in modern evidence-based medicine. Advantages of collecting data from more than one site are numerous, including accelerated recruitment and increased generalisability of results. Mixed models can be applied to account for potential clustering in the data, in particular when many small centres contribute patients to the study. Previously proposed methods on sample size calculation for mixed models only considered balanced treatment allocations which is an unlikely outcome in practice if block randomisation with reasonable choices of block length is used. SN - 1471-2288 UR - https://doi.org/10.1186/s12874-018-0602-y DO - 10.1186/s12874-018-0602-y ID - Harden2018 ER -