Retraction to: Quality of Life Research (2017) 26:2321–2331 https://doi.org/10.1007/s11136-017-1576-7

The authors have retracted this article [1]. Contrary to the statement in the article, the Institutional Review Board of the University of Hong Kong/Hospital Authority Hong Kong West Cluster issued a Notice of Termination of Approval on 16 June 2014 which carried the meaning of withdrawal of approval. All authors agree with this retraction.