The rising relative risk of mortality for singles: meta-analysis and meta-regression.

Never-married persons (singles) constitute a growing demographic group; yet, the magnitude of the all-cause relative mortality risk for nonelderly singles is not known and important moderating factors have not been explored. The authors used meta-analysis to examine 641 risk estimates from 95 publications that provided data on more than 500 million persons. The comparison group consisted of currently married individuals.