Updating M6 pregnancy of unknown location risk‐prediction model including evaluation of clinical factors

ABSTRACT Objectives Ectopic pregnancy (EP) is a major high‐risk outcome following a pregnancy of unknown location (PUL) classification. Biochemical markers are used to triage PUL as high vs low risk to guide appropriate follow‐up. The M6 model is currently the best risk‐prediction model. We aimed to...

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Veröffentlicht in:Ultrasound in obstetrics & gynecology Jg. 63; H. 3; S. 408 - 418
Hauptverfasser: Kyriacou, C., Ledger, A., Bobdiwala, S., Ayim, F., Kirk, E., Abughazza, O., Guha, S., Vathanan, V., Gould, D., Timmerman, D., Van Calster, B., Bourne, T., Pikovsky, M., Mitchell‐Jones, N., Parker, N., Barcroft, J., Kapur, S., Chohan, B., Guruwadahyarhalli, B., Stalder, C., Al‐Memar, M.
Format: Journal Article
Sprache:Englisch
Veröffentlicht: Chichester, UK John Wiley & Sons, Ltd 01.03.2024
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ISSN:0960-7692, 1469-0705, 1469-0705
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Abstract ABSTRACT Objectives Ectopic pregnancy (EP) is a major high‐risk outcome following a pregnancy of unknown location (PUL) classification. Biochemical markers are used to triage PUL as high vs low risk to guide appropriate follow‐up. The M6 model is currently the best risk‐prediction model. We aimed to update the M6 model and evaluate whether performance can be improved by including clinical factors. Methods This prospective cohort study recruited consecutive PUL between January 2015 and January 2017 at eight units (Phase 1), with two centers continuing recruitment between January 2017 and March 2021 (Phase 2). Serum samples were collected routinely and sent for β‐human chorionic gonadotropin (β‐hCG) and progesterone measurement. Clinical factors recorded were maternal age, pain score, bleeding score and history of EP. Based on transvaginal ultrasonography and/or biochemical confirmation during follow‐up, PUL were classified subsequently as failed PUL (FPUL), intrauterine pregnancy (IUP) or EP (including persistent PUL (PPUL)). The M6 models with (M6P) and without (M6NP) progesterone were refitted and extended with clinical factors. Model validation was performed using internal–external cross‐validation (IECV) (Phase 1) and temporal external validation (EV) (Phase 2). Missing values were handled using multiple imputation. Results Overall, 5473 PUL were recruited over both phases. A total of 709 PUL were excluded because maternal age was < 16 years or initial β‐hCG was ≤ 25 IU/L, leaving 4764 (87%) PUL for analysis (2894 in Phase 1 and 1870 in Phase 2). For the refitted M6P model, the area under the receiver‐operating‐characteristics curve (AUC) for EP/PPUL vs IUP/FPUL was 0.89 for IECV and 0.84–0.88 for EV, with respective sensitivities of 94% and 92–93%. For the refitted M6NP model, the AUCs were 0.85 for IECV and 0.82–0.86 for EV, with respective sensitivities of 92% and 93–94%. Calibration performance was good overall, but with heterogeneity between centers. Net Benefit confirmed clinical utility. The change in AUC when M6P was extended to include maternal age, bleeding score and history of EP was between −0.02 and 0.01, depending on center and phase. The corresponding change in AUC when M6NP was extended was between −0.01 and 0.03. At the 5% threshold to define high risk of EP/PPUL, extending M6P altered sensitivity by −0.02 to −0.01, specificity by 0.03 to 0.04 and Net Benefit by −0.005 to 0.006. Extending M6NP altered sensitivity by −0.03 to −0.01, specificity by 0.05 to 0.07 and Net Benefit by −0.005 to 0.006. Conclusions The updated M6 model offers accurate diagnostic performance, with excellent sensitivity for EP. Adding clinical factors to the model improved performance in some centers, especially when progesterone levels were not suitable or unavailable. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
AbstractList Objectives Ectopic pregnancy (EP) is a major high‐risk outcome following a pregnancy of unknown location (PUL) classification. Biochemical markers are used to triage PUL as high vs low risk to guide appropriate follow‐up. The M6 model is currently the best risk‐prediction model. We aimed to update the M6 model and evaluate whether performance can be improved by including clinical factors. Methods This prospective cohort study recruited consecutive PUL between January 2015 and January 2017 at eight units (Phase 1), with two centers continuing recruitment between January 2017 and March 2021 (Phase 2). Serum samples were collected routinely and sent for β‐human chorionic gonadotropin (β‐hCG) and progesterone measurement. Clinical factors recorded were maternal age, pain score, bleeding score and history of EP. Based on transvaginal ultrasonography and/or biochemical confirmation during follow‐up, PUL were classified subsequently as failed PUL (FPUL), intrauterine pregnancy (IUP) or EP (including persistent PUL (PPUL)). The M6 models with (M6P) and without (M6NP) progesterone were refitted and extended with clinical factors. Model validation was performed using internal–external cross‐validation (IECV) (Phase 1) and temporal external validation (EV) (Phase 2). Missing values were handled using multiple imputation. Results Overall, 5473 PUL were recruited over both phases. A total of 709 PUL were excluded because maternal age was < 16 years or initial β‐hCG was ≤ 25 IU/L, leaving 4764 (87%) PUL for analysis (2894 in Phase 1 and 1870 in Phase 2). For the refitted M6P model, the area under the receiver‐operating‐characteristics curve (AUC) for EP/PPUL vs IUP/FPUL was 0.89 for IECV and 0.84–0.88 for EV, with respective sensitivities of 94% and 92–93%. For the refitted M6NP model, the AUCs were 0.85 for IECV and 0.82–0.86 for EV, with respective sensitivities of 92% and 93–94%. Calibration performance was good overall, but with heterogeneity between centers. Net Benefit confirmed clinical utility. The change in AUC when M6P was extended to include maternal age, bleeding score and history of EP was between −0.02 and 0.01, depending on center and phase. The corresponding change in AUC when M6NP was extended was between −0.01 and 0.03. At the 5% threshold to define high risk of EP/PPUL, extending M6P altered sensitivity by −0.02 to −0.01, specificity by 0.03 to 0.04 and Net Benefit by −0.005 to 0.006. Extending M6NP altered sensitivity by −0.03 to −0.01, specificity by 0.05 to 0.07 and Net Benefit by −0.005 to 0.006. Conclusions The updated M6 model offers accurate diagnostic performance, with excellent sensitivity for EP. Adding clinical factors to the model improved performance in some centers, especially when progesterone levels were not suitable or unavailable. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
ABSTRACT Objectives Ectopic pregnancy (EP) is a major high‐risk outcome following a pregnancy of unknown location (PUL) classification. Biochemical markers are used to triage PUL as high vs low risk to guide appropriate follow‐up. The M6 model is currently the best risk‐prediction model. We aimed to update the M6 model and evaluate whether performance can be improved by including clinical factors. Methods This prospective cohort study recruited consecutive PUL between January 2015 and January 2017 at eight units (Phase 1), with two centers continuing recruitment between January 2017 and March 2021 (Phase 2). Serum samples were collected routinely and sent for β‐human chorionic gonadotropin (β‐hCG) and progesterone measurement. Clinical factors recorded were maternal age, pain score, bleeding score and history of EP. Based on transvaginal ultrasonography and/or biochemical confirmation during follow‐up, PUL were classified subsequently as failed PUL (FPUL), intrauterine pregnancy (IUP) or EP (including persistent PUL (PPUL)). The M6 models with (M6P) and without (M6NP) progesterone were refitted and extended with clinical factors. Model validation was performed using internal–external cross‐validation (IECV) (Phase 1) and temporal external validation (EV) (Phase 2). Missing values were handled using multiple imputation. Results Overall, 5473 PUL were recruited over both phases. A total of 709 PUL were excluded because maternal age was < 16 years or initial β‐hCG was ≤ 25 IU/L, leaving 4764 (87%) PUL for analysis (2894 in Phase 1 and 1870 in Phase 2). For the refitted M6P model, the area under the receiver‐operating‐characteristics curve (AUC) for EP/PPUL vs IUP/FPUL was 0.89 for IECV and 0.84–0.88 for EV, with respective sensitivities of 94% and 92–93%. For the refitted M6NP model, the AUCs were 0.85 for IECV and 0.82–0.86 for EV, with respective sensitivities of 92% and 93–94%. Calibration performance was good overall, but with heterogeneity between centers. Net Benefit confirmed clinical utility. The change in AUC when M6P was extended to include maternal age, bleeding score and history of EP was between −0.02 and 0.01, depending on center and phase. The corresponding change in AUC when M6NP was extended was between −0.01 and 0.03. At the 5% threshold to define high risk of EP/PPUL, extending M6P altered sensitivity by −0.02 to −0.01, specificity by 0.03 to 0.04 and Net Benefit by −0.005 to 0.006. Extending M6NP altered sensitivity by −0.03 to −0.01, specificity by 0.05 to 0.07 and Net Benefit by −0.005 to 0.006. Conclusions The updated M6 model offers accurate diagnostic performance, with excellent sensitivity for EP. Adding clinical factors to the model improved performance in some centers, especially when progesterone levels were not suitable or unavailable. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Ectopic pregnancy (EP) is a major high-risk outcome following a pregnancy of unknown location (PUL) classification. Biochemical markers are used to triage PUL as high vs low risk to guide appropriate follow-up. The M6 model is currently the best risk-prediction model. We aimed to update the M6 model and evaluate whether performance can be improved by including clinical factors. This prospective cohort study recruited consecutive PUL between January 2015 and January 2017 at eight units (Phase 1), with two centers continuing recruitment between January 2017 and March 2021 (Phase 2). Serum samples were collected routinely and sent for β-human chorionic gonadotropin (β-hCG) and progesterone measurement. Clinical factors recorded were maternal age, pain score, bleeding score and history of EP. Based on transvaginal ultrasonography and/or biochemical confirmation during follow-up, PUL were classified subsequently as failed PUL (FPUL), intrauterine pregnancy (IUP) or EP (including persistent PUL (PPUL)). The M6 models with (M6 ) and without (M6 ) progesterone were refitted and extended with clinical factors. Model validation was performed using internal-external cross-validation (IECV) (Phase 1) and temporal external validation (EV) (Phase 2). Missing values were handled using multiple imputation. Overall, 5473 PUL were recruited over both phases. A total of 709 PUL were excluded because maternal age was < 16 years or initial β-hCG was ≤ 25 IU/L, leaving 4764 (87%) PUL for analysis (2894 in Phase 1 and 1870 in Phase 2). For the refitted M6 model, the area under the receiver-operating-characteristics curve (AUC) for EP/PPUL vs IUP/FPUL was 0.89 for IECV and 0.84-0.88 for EV, with respective sensitivities of 94% and 92-93%. For the refitted M6 model, the AUCs were 0.85 for IECV and 0.82-0.86 for EV, with respective sensitivities of 92% and 93-94%. Calibration performance was good overall, but with heterogeneity between centers. Net Benefit confirmed clinical utility. The change in AUC when M6 was extended to include maternal age, bleeding score and history of EP was between -0.02 and 0.01, depending on center and phase. The corresponding change in AUC when M6 was extended was between -0.01 and 0.03. At the 5% threshold to define high risk of EP/PPUL, extending M6 altered sensitivity by -0.02 to -0.01, specificity by 0.03 to 0.04 and Net Benefit by -0.005 to 0.006. Extending M6 altered sensitivity by -0.03 to -0.01, specificity by 0.05 to 0.07 and Net Benefit by -0.005 to 0.006. The updated M6 model offers accurate diagnostic performance, with excellent sensitivity for EP. Adding clinical factors to the model improved performance in some centers, especially when progesterone levels were not suitable or unavailable. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Ectopic pregnancy (EP) is a major high-risk outcome following a pregnancy of unknown location (PUL) classification. Biochemical markers are used to triage PUL as high vs low risk to guide appropriate follow-up. The M6 model is currently the best risk-prediction model. We aimed to update the M6 model and evaluate whether performance can be improved by including clinical factors.OBJECTIVESEctopic pregnancy (EP) is a major high-risk outcome following a pregnancy of unknown location (PUL) classification. Biochemical markers are used to triage PUL as high vs low risk to guide appropriate follow-up. The M6 model is currently the best risk-prediction model. We aimed to update the M6 model and evaluate whether performance can be improved by including clinical factors.This prospective cohort study recruited consecutive PUL between January 2015 and January 2017 at eight units (Phase 1), with two centers continuing recruitment between January 2017 and March 2021 (Phase 2). Serum samples were collected routinely and sent for β-human chorionic gonadotropin (β-hCG) and progesterone measurement. Clinical factors recorded were maternal age, pain score, bleeding score and history of EP. Based on transvaginal ultrasonography and/or biochemical confirmation during follow-up, PUL were classified subsequently as failed PUL (FPUL), intrauterine pregnancy (IUP) or EP (including persistent PUL (PPUL)). The M6 models with (M6P ) and without (M6NP ) progesterone were refitted and extended with clinical factors. Model validation was performed using internal-external cross-validation (IECV) (Phase 1) and temporal external validation (EV) (Phase 2). Missing values were handled using multiple imputation.METHODSThis prospective cohort study recruited consecutive PUL between January 2015 and January 2017 at eight units (Phase 1), with two centers continuing recruitment between January 2017 and March 2021 (Phase 2). Serum samples were collected routinely and sent for β-human chorionic gonadotropin (β-hCG) and progesterone measurement. Clinical factors recorded were maternal age, pain score, bleeding score and history of EP. Based on transvaginal ultrasonography and/or biochemical confirmation during follow-up, PUL were classified subsequently as failed PUL (FPUL), intrauterine pregnancy (IUP) or EP (including persistent PUL (PPUL)). The M6 models with (M6P ) and without (M6NP ) progesterone were refitted and extended with clinical factors. Model validation was performed using internal-external cross-validation (IECV) (Phase 1) and temporal external validation (EV) (Phase 2). Missing values were handled using multiple imputation.Overall, 5473 PUL were recruited over both phases. A total of 709 PUL were excluded because maternal age was < 16 years or initial β-hCG was ≤ 25 IU/L, leaving 4764 (87%) PUL for analysis (2894 in Phase 1 and 1870 in Phase 2). For the refitted M6P model, the area under the receiver-operating-characteristics curve (AUC) for EP/PPUL vs IUP/FPUL was 0.89 for IECV and 0.84-0.88 for EV, with respective sensitivities of 94% and 92-93%. For the refitted M6NP model, the AUCs were 0.85 for IECV and 0.82-0.86 for EV, with respective sensitivities of 92% and 93-94%. Calibration performance was good overall, but with heterogeneity between centers. Net Benefit confirmed clinical utility. The change in AUC when M6P was extended to include maternal age, bleeding score and history of EP was between -0.02 and 0.01, depending on center and phase. The corresponding change in AUC when M6NP was extended was between -0.01 and 0.03. At the 5% threshold to define high risk of EP/PPUL, extending M6P altered sensitivity by -0.02 to -0.01, specificity by 0.03 to 0.04 and Net Benefit by -0.005 to 0.006. Extending M6NP altered sensitivity by -0.03 to -0.01, specificity by 0.05 to 0.07 and Net Benefit by -0.005 to 0.006.RESULTSOverall, 5473 PUL were recruited over both phases. A total of 709 PUL were excluded because maternal age was < 16 years or initial β-hCG was ≤ 25 IU/L, leaving 4764 (87%) PUL for analysis (2894 in Phase 1 and 1870 in Phase 2). For the refitted M6P model, the area under the receiver-operating-characteristics curve (AUC) for EP/PPUL vs IUP/FPUL was 0.89 for IECV and 0.84-0.88 for EV, with respective sensitivities of 94% and 92-93%. For the refitted M6NP model, the AUCs were 0.85 for IECV and 0.82-0.86 for EV, with respective sensitivities of 92% and 93-94%. Calibration performance was good overall, but with heterogeneity between centers. Net Benefit confirmed clinical utility. The change in AUC when M6P was extended to include maternal age, bleeding score and history of EP was between -0.02 and 0.01, depending on center and phase. The corresponding change in AUC when M6NP was extended was between -0.01 and 0.03. At the 5% threshold to define high risk of EP/PPUL, extending M6P altered sensitivity by -0.02 to -0.01, specificity by 0.03 to 0.04 and Net Benefit by -0.005 to 0.006. Extending M6NP altered sensitivity by -0.03 to -0.01, specificity by 0.05 to 0.07 and Net Benefit by -0.005 to 0.006.The updated M6 model offers accurate diagnostic performance, with excellent sensitivity for EP. Adding clinical factors to the model improved performance in some centers, especially when progesterone levels were not suitable or unavailable. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.CONCLUSIONSThe updated M6 model offers accurate diagnostic performance, with excellent sensitivity for EP. Adding clinical factors to the model improved performance in some centers, especially when progesterone levels were not suitable or unavailable. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Author Abughazza, O.
Timmerman, D.
Van Calster, B.
Ayim, F.
Pikovsky, M.
Guruwadahyarhalli, B.
Bourne, T.
Barcroft, J.
Mitchell‐Jones, N.
Ledger, A.
Bobdiwala, S.
Kirk, E.
Chohan, B.
Al‐Memar, M.
Vathanan, V.
Gould, D.
Guha, S.
Stalder, C.
Kapur, S.
Parker, N.
Kyriacou, C.
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BackLink https://www.ncbi.nlm.nih.gov/pubmed/37842861$$D View this record in MEDLINE/PubMed
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ContentType Journal Article
Contributor Kapur, S
Barcroft, J
Guruwadahyarhalli, B
Al-Memar, M
Parker, N
Stalder, C
Mitchell-Jones, N
Chohan, B
Pikovsky, M
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Copyright 2023 The Authors. published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
2023. This work is published under Creative Commons Attribution License~https://creativecommons.org/licenses/by/3.0/ (the "License"). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.
Copyright_xml – notice: 2023 The Authors. published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
– notice: 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
– notice: 2023. This work is published under Creative Commons Attribution License~https://creativecommons.org/licenses/by/3.0/ (the "License"). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.
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DOI 10.1002/uog.27515
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Issue 3
Keywords β-hCG
pregnancy of unknown location
modeling
β-human chorionic gonadotropin
PUL
progesterone
Language English
License Attribution
2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
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Snippet ABSTRACT Objectives Ectopic pregnancy (EP) is a major high‐risk outcome following a pregnancy of unknown location (PUL) classification. Biochemical markers are...
Ectopic pregnancy (EP) is a major high-risk outcome following a pregnancy of unknown location (PUL) classification. Biochemical markers are used to triage PUL...
Objectives Ectopic pregnancy (EP) is a major high‐risk outcome following a pregnancy of unknown location (PUL) classification. Biochemical markers are used to...
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SubjectTerms Adolescent
Age
Area Under Curve
Biochemical markers
Bleeding
Calibration
Chorionic gonadotropin
Chorionic Gonadotropin, beta Subunit, Human
Ectopic pregnancy
Female
Gonadotropins
Gynecology
Heterogeneity
Humans
modeling
Obstetrics
Performance evaluation
Pituitary (anterior)
Prediction models
Pregnancy
Pregnancy complications
pregnancy of unknown location
Pregnancy, Ectopic - diagnostic imaging
Progesterone
Prospective Studies
PUL
Risk
Sensitivity
Ultrasonic imaging
Ultrasound
β‐hCG
β‐human chorionic gonadotropin
Title Updating M6 pregnancy of unknown location risk‐prediction model including evaluation of clinical factors
URI https://onlinelibrary.wiley.com/doi/abs/10.1002%2Fuog.27515
https://www.ncbi.nlm.nih.gov/pubmed/37842861
https://www.proquest.com/docview/2933419610
https://www.proquest.com/docview/2878016596
Volume 63
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