Computerised cardiotocography—study design hampers findings
Authors: Michael A Belfort, Steven L Clark
Journal: The Lancet (2017)

Cardiotocography is a diagnostic tool, not a therapeutic modality. Diagnostic tests are unlikely to improve outcomes unless followed by specific and effective therapeutic interventions. When the management of highly specific abnormalities is not specified in a study protocol but is instead left to the individual discretion of many providers with very different management approaches, the chance that all of them will react in the same way is small. In The Lancet, the INFANT collaborative group reports the results of a randomised controlled trial1The INFANT Collaborative GroupComputerised interpretation of fetal heart rate during labour (INFANT): a randomised controlled trial.Lancet. 2017; (published online March 21.)http://dx.doi.org/10.1016/S0140-6736(17)30568-8Google Scholar in which women in labour undergoing electronic cardiotocographic monitoring were randomly allocated with or without assessment by a decision-support system. The decision-support software extracted data including baseline heart rate, heart-rate variability, accelerations, type and timing of decelerations, the quality of the signal, and the contraction pattern, analysed these data along with the quality of the signals, and then presented the findings as a series of colour-coded alerts, the most serious of which was a red alert. No specific actions on the part of the providers were defined as a result of receiving these alerts. The primary outcomes were a composite of poor neonatal outcome or significant morbidity, and developmental assessment at age 2 years in a subset of surviving children. The authors found no significant difference in the incidence of poor neonatal outcome between the groups (adjusted risk ratio 1·01, 95% CI 0·82–1·25). Furthermore, they found no differences in most of the secondary maternal, neonatal, or long-term outcomes. They concluded that no evidence currently supports the use of computerised interpretation of cardiotocography in labour to improve clinical outcomes for mothers or babies. The IQR of time from identification of the last red level of concern to birth was 13–279 min. This finding suggests widely disparate approaches to even severe cardiotocographic abnormalities in the study. The INFANT trial seems to be open to the same criticism levelled at studies2Clark SL Nageotte MP Garite TJ et al.Management of category II fetal heart rate tracings: toward standardization of care.Am J Obstet Gynecol. 2013; 209: 89-97Summary Full Text Full Text PDF PubMed Scopus (114) Google Scholar, 3Haverkamp AD Orleans M Langendorf S et al.A controlled trial of differential effects of intrapartum fetal monitoring.Am J Obstet Gynecol. 1979; 134: 399-412Summary Full Text PDF PubMed Scopus (331) Google Scholar in which women in labour were randomly assigned to auscultation or cardiotocography. Without an unambiguous reaction to clearly defined abnormal patterns, these studies could compare outcomes only between women who did or did not wear a monitor belt during labour, rather than show any intrinsic value of cardiotocographic technology.2Clark SL Nageotte MP Garite TJ et al.Management of category II fetal heart rate tracings: toward standardization of care.Am J Obstet Gynecol. 2013; 209: 89-97Summary Full Text Full Text PDF PubMed Scopus (114) Google Scholar, 3Haverkamp AD Orleans M Langendorf S et al.A controlled trial of differential effects of intrapartum fetal monitoring.Am J Obstet Gynecol. 1979; 134: 399-412Summary Full Text PDF PubMed Scopus (331) Google Scholar We also question the authors' apparent dismissal of the value of computerised cardiotocographic interpretation simply because the algorithm used in their trial was not beneficial. This dismissal would be a substantial problem even in the setting of uniform response to specified abnormal signals. The fault could lie with the specific algorithm and system of alerts and not with computer waveform interpretation per se. Computer-aided detection is a promising technology that has been successfully applied to the detection of malignancy, including breast and prostate imaging, but is dependent on the integration of an effective diagnostic algorithm into the software.4Meinel LA Stolpen AH Berbaum KS et al.Breast MRI lesion classification: improved performance of human readers with a backpropagation neural network computer-aided diagnosis (CAD).J Magn Reson Iimaging. 2007; 25: 89-95Crossref PubMed Scopus (140) Google Scholar, 5Hambrock T Vos PC Hulsbergen-van de Kaa JO et al.Prostate cancer: computer-aided diagnosis with multiparametric #-T MR imaging—effect of observer performance.Radiology. 2013; 266: 521-530Crossref PubMed Scopus (97) Google Scholar, 6Fenton JJ Taplin SH Carney PA et al.Influence of computer-aided detection on performance of screening mammography.New Eng J Med. 2007; 356: 1399-1409Crossref PubMed Scopus (429) Google Scholar In the INFANT study,1The INFANT Collaborative GroupComputerised interpretation of fetal heart rate during labour (INFANT): a randomised controlled trial.Lancet. 2017; (published online March 21.)http://dx.doi.org/10.1016/S0140-6736(17)30568-8Google Scholar we wonder whether an algorithm in which the last red level of concern was judged to be of actual concern in only 55% of cases, and which mistook maternal for fetal heart rate in 70% of the remaining tracings, is ideal. Improved outcomes with uniform response to the right cardiotocographic algorithm has been previously demonstrated with visual interpretation only—no evidence suggests that computerised interpretation would be different if properly investigated.3Haverkamp AD Orleans M Langendorf S et al.A controlled trial of differential effects of intrapartum fetal monitoring.Am J Obstet Gynecol. 1979; 134: 399-412Summary Full Text PDF PubMed Scopus (331) Google Scholar, 7Clark SL Meyers JA Frye DR et al.Recognition and response to electronic fetal heart rate patterns—impact on newborn outcomes and primary cesarean delivery rate in women undergoing induction of labor.Am J Obstet Gynecol. 2015; 212: 494PubMed Google Scholar, 8Clark SL Hamilton EH Garite TJ et al.The limits of electronic fetal heart rate monitoring in the prevention of neonatal academia.Am J Obstet Gynecol. 2016; (published online Oct 16, 2016.)https://doi.org/10.1016/j.ajog.2016.10.009Summary Full Text Full Text PDF Scopus (82) Google Scholar Strengths of this study include its large size and the availability of long-term follow up of infants studied. Additionally, the authors should be commended for their publication of negative findings. In view of the time and effort the investigators put into this study, it is unfortunate that an unambiguous, standardised management protocol (most importantly, delivery vs no delivery) was not specified in response to well defined cardiotocographic patterns. Such a management protocol could have been combined with post-hoc monitoring of compliance. Even the best diagnostic test is of no value in the absence of appropriate test use. The superiority of computers to human beings in the analysis of complex patterns is well established in many arenas; the authors' data do not establish computerised cardiotocographic interpretation as an exception to this general rule. The application of artificial intelligence to medical diagnosis is one of the most exciting and promising areas of medicine.9Vemulapalli V Qu J Garren JM et al.Non-obvioius correlations to disease management unraveled by Bayesian artificial intelligence.Artif Intell Med. 2016; 74: 1-8Summary Full Text Full Text PDF PubMed Scopus (27) Google Scholar, 10Kshivets O PS01.40: artificial intelligence, systems analysis and simulation modeling in optimization of management for lung cancer patients.J Thorac Oncol. 2016; 11: S293-S294Summary Full Text Full Text PDF PubMed Google Scholar Whether cardiotocographic analysis will join the list of clinically valuable computer-enhanced diagnostic techniques remains to be seen. Although the INFANT collaborative group did not provide evidence of benefit for cardiotocographic analysis, we believe that the findings of this study should not discourage other researchers from investigation of these techniques in the assessment of fetal tolerance of labour. We declare no competing interests. Computerised interpretation of fetal heart rate during labour (INFANT): a randomised controlled trialUse of computerised interpretation of cardiotocographs in women who have continuous electronic fetal monitoring in labour does not improve clinical outcomes for mothers or babies. Full-Text PDF Open AccessThe INFANT trialRobert Keith1 (April 28, p 1697) suggests that the INFANT trial2 is flawed by design. Previous reports3,4 suggested that a key element in substandard intrapartum care is the failure of clinicians to recognise an abnormal fetal heart-rate pattern, so the trial was set up to investigate whether decision support that detects and highlights abnormality of the fetal heart rate could improve outcomes. We compared decision support with no decision support. All other aspects of care were kept constant, including the use of the Guardian platform, which is the electronic data collection system in which the decision-support software operates. 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