Mindfulness interventions for physical and psychological outcomes in cancer patients and caregivers: non-English literature may be lost in translation due to language bias

Although mindfulness practices have originated in East Asia, including non-English literature in systematic reviews of mindfulness interventions for cancer care will enable researchers to explore its application in various cultural contexts.

A systematic analysis of online bibliographic databases: AMED, Embase, CINHAL, LILACS, MEDLINE, ProQuest Central, PsycINFO, PsycArticles, and WoS revealed that non-English literature accounted for 2.72% of original research papers on mindfulness where no language restriction was applied.

This suggests that the exclusion of non-English literature in systematic reviews on mindfulness interventions for cancer care may not lead to a biased effect size if a search is restricted to articles indexed in an English language-specific database.

In comparison, an exploratory analysis of the China National Knowledge Infrastructure database revealed a higher percentage, up to 19.2% of indexed non-English language literature.

The authors caution that results of systematic reviews of mindfulness interventions that exclude non-English databases may still constitute a biased generalizability because most literature published in non-English journals are not indexed in major research databases.