We chose to alter the way in which the assessment of methodological quality was conducted and focus on a risk of bias assessment as a more useful analysis of the individual trials rather than using the tool originally described in the protocol.

Rather than using fixed effect modelling for continuous data as per the protocol the authors determined that a random‐effects model was more appropriate for the relatively heterogeneous nature of herbal medicines. It would not be expected that different herbal formulations would produce the same quantity but that the different interventions would produce a distribution in magnitude of effects on any given outcome.

Dichotomous data were expressed as relative risk (RR) ratios rather than odds ratios (OR). This method has been changed since the publication of the protocol to reflect the approach used by other studies in this modality of treatment. It is also a more easily understood statistic in presenting these outcomes.

A high level of statistical heterogeneity was found in the comparison of Chinese herbal medicines with lifestyle modification vs lifestyle modification alone on nearly all outcomes. For this reason subgroup analyses were undertaken. Due to the nature of the trials included the subgroup analyses varied from those set out in the trial protocol.

The database CISCOM was not searched as it is no longer active.