Single versus pairwise interpretation of cardiotochography, a comparative study from six Swedish delivery units

Abstract

Objective: The aim of the study was to evaluate whether interpreting CTG pairwise brings about a higher level of correctly classified CTG recordings in a non-selected population of midwives and physicians.

Study design: A comparative study.

Setting: Five delivery units in Stockholm and one delivery unit in Uppsala, with 1589, 3740, 3908, 4539, 6438, and 7331 deliveries in 2011, respectively.

Subjects: 536 midwives and physicians classified one randomly selected CTG recording individually followed by a pairwise classification. The pairs consisted of two midwives (119 pairs) or one midwife and one physician (149 pairs), a total of 268 pairs.

Main outcome measure: The proportion of individually correctly classified CTG recordings versus the proportion of pairwise correctly classified CTG recordings.

Results: The proportion of individually correctly classified CTG's was 75% and the proportion of pairwise correctly classified CTG's was 80% (difference 5%, p = 0.12).

Conclusions: There was no statistically significant difference when CTG's were classified pairwise compared to individual classifications. The proportion of individually correctly classified CTG's was high (75%). There were differences in the proportion of correctly classified CTG recordings between the delivery units, indicating potential areas of improvement.

Keywords: Cardiotocography; Cardiotocography interpretation; Fetal surveillance; Intrapartum; Pairwise interpretation.