On 2016 Nov 18, James C Coyne commented:

This meta-analysis provides a misleading estimate of the efficacy of mindfulness-based stress reduction for cancer patients. Only two of the nine studies entered into the meta-analysis were actually RCTs. One found noa significant effect of mindfulness on the outcome variables, the other, an effect for only one of three outcomes. The claims of "moderate-to-large" effects depend on small, uncontrolled, nonrandomized trials. There was no rating of quality of trials or risk of bias, and therefore no taking of the poor quality of the trials into account. Trials of mindfulness are known to have high risk of bias and inadequate control groups.

Given the rush to implement mindfulness interventions in psychosocial care of cancer patients, there is need for independent assessment of whether there is any benefit. This review does not provide a valid assessmen.

An extended critique of this study can be found at https://jcoynester.wordpress.com/2016/11/18/mindfulness-based-stress-reduction-to-improve-the-mental-health-of-breast-cancer-patients/

On 2016 Nov 18, James C Coyne commented:

This meta-analysis provides a misleading estimate of the efficacy of mindfulness-based stress reduction for cancer patients. Only two of the nine studies entered into the meta-analysis were actually RCTs. One found noa significant effect of mindfulness on the outcome variables, the other, an effect for only one of three outcomes. The claims of "moderate-to-large" effects depend on small, uncontrolled, nonrandomized trials. There was no rating of quality of trials or risk of bias, and therefore no taking of the poor quality of the trials into account. Trials of mindfulness are known to have high risk of bias and inadequate control groups.

Given the rush to implement mindfulness interventions in psychosocial care of cancer patients, there is need for independent assessment of whether there is any benefit. This review does not provide a valid assessmen.

An extended critique of this study can be found at https://jcoynester.wordpress.com/2016/11/18/mindfulness-based-stress-reduction-to-improve-the-mental-health-of-breast-cancer-patients/