Maternal satisfaction as an outcome criterion in research on labor analgesia: data analysis from the recent...

To investigate whether maternal satisfaction (MS) is taken into consideration as an outcome criterion in clinical research on analgesia for labor.

A systematic review of articles reporting analgesia for labor from a panel of 17 influential journals was undertaken. A total of 116 articles were analyzed, including 282 within-study groups. The scope of MS, the type of outcome measure used, and the time of measurement were noted. Each available observation was assigned an ordinal value of MS (ordMS), according to data distribution. The factors influencing ordMS were identified by multivariable analysis.

The methods used to assess MS were very variable, even within the different measurement tools reported. The weighted distribution of ordMS was 17.8%, 21.8%, 31.2%, and 29.3% for levels "poor," "fair," "good," and "excellent," respectively. In comparative studies, statistical differences for analgesia were related to statistical differences for MS (P<0.0001), but only the negative predictive value was high (0.87). Power to detect a difference in MS between treatment groups was low in general, but it influenced reporting of a significant difference for MS (P<0.0001). The obstetrical factors influencing ordMS were: the body mass index, the initial cervical dilatation, and the within-study percentage of nulliparous women. The techniques alternative to epidural analgesia negatively influenced ordMS.

A standard and validated tool to assess MS in clinical research on analgesia for labor is still to be developed. Power should be improved by acting on sample sizes or sensitivity of the outcome.