Obstet Gynecol Sci.  2017 Jul;60(4):343-349. 10.5468/ogs.2017.60.4.343.

Evaluation of the learning curve for external cephalic version using cumulative sum analysis

• Kim SY
• Han JY
• Chang EH
• Kwak DW
• Ahn HK
• Ryu HM
• Kim MY

• KMID: 2386275
• DOI: http://doi.org/10.5468/ogs.2017.60.4.343

Abstract

OBJECTIVE
We evaluated the learning curve for external cephalic version (ECV) using learning curve-cumulative sum (LC-CUSUM) analysis.
METHODS
This was a retrospective study involving 290 consecutive cases between October 2013 and March 2017. We evaluated the learning curve for ECV on nulli and over para 1 group using LC-CUSUM analysis on the assumption that 50% and 70% of ECV procedures succeeded by description a trend-line of quadratic function with reliable R² values.
RESULTS
The overall success rate for ECV was 64.8% (188/290), while the success rate for nullipara and over para 1 groups was 56.2% (100/178) and 78.6% (88/112), respectively. "˜H' value, that the actual failure rate does not differ from the acceptable failure rate, was −3.27 and −1.635 when considering ECV success rates of 50% and 70%, respectively. Consequently, in order to obtain a consistent 50% success rate, we would require 57 nullipara cases, and in order to obtain a consistent 70% success rate, we would require 130 nullipara cases. In contrast, 8 to 10 over para 1 cases would be required for an expected success rate of 50% and 70% on over para 1 group.
CONCLUSION
Even a relatively inexperienced physician can experience success with multipara and after accumulating experience, they will manage nullipara cases. Further research is required for LC-CUSUM involving several practitioners instead of a single practitioner. This will lead to the gradual implementation of standard learning curve guidelines for ECV.

Keyword

Amniotic fluid; Breech presentation; Learning curve; Version, fetal

MeSH Terms

Amniotic Fluid
Breech Presentation
Female
Learning Curve*
Learning*
Pregnancy
Retrospective Studies
Version, Fetal*

Figure

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  Fig. 1 Overall cumulative sum (CUSUM) score of total patients. (A) Acceptable external cephalic version failure rate of 50%. (B) Acceptable external cephalic version failure rate of 30%.

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  Fig. 2 Cumulative sum (CUSUM) score of nullipara patients. (A) Acceptable external cephalic version failure rate of 50%. (B) Acceptable external cephalic version failure rate of 30%.

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  Fig. 3 Cumulative sum (CUSUM) score of over para 1 patients. (A) Acceptable external cephalic version failure rate of 50%. (B) Acceptable external cephalic version failure rate of 30%.

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