Population Health Metrics Research Consortium gold standard verbal autopsy validation study: design, implementation, and development of analysis datasets.

Christopher J L Murray ,Mwanaidi Said,Saurabh Mehta,Sara Gómez,Vinita Das,Vishwajeet Kumar,Rohina Joshi,Alan D Lopez,Diozele Sanvictores,Dolores Ramírez-Villalobos,Summer Lockett Ohno,Rajendra Prasad,Ramesh Ahuja,Emily Dantzer,Sunil Sazawal,Ian Riley,Veronica Tallo,Bruce Neal,Aarti Kumar,Rafael Lozano,Bernardo Hernández,Devarsetty Praveen,Lalit Dandona,Hazel Remolador,Zul Premji,Marilla Lucero,Minerva Romero,Usha Dhingra,Henry D Kalter ,Abdullah H Baqui ,Wafaie W Fawzi ,Robert E Black ,Anindya Dutta ,Said M Ali ,Abraham D Flaxman

doi:10.1186/1478-7954-9-27

Abstract

BackgroundVerbal autopsy methods are critically important for evaluating the leading causes of death in populations without adequate vital registration systems. With a myriad of analytical and data collection approaches, it is essential to create a high quality validation dataset from different populations to evaluate comparative method performance and make recommendations for future verbal autopsy implementation. This study was undertaken to compile a set of strictly defined gold standard deaths for which verbal autopsies were collected to validate the accuracy of different methods of verbal autopsy cause of death assignment.MethodsData collection was implemented in six sites in four countries: Andhra Pradesh, India; Bohol, Philippines; Dar es Salaam, Tanzania; Mexico City, Mexico; Pemba Island, Tanzania; and Uttar Pradesh, India. The Population Health Metrics Research Consortium (PHMRC) developed stringent diagnostic criteria including laboratory, pathology, and medical imaging findings to identify gold standard deaths in health facilities as well as an enhanced verbal autopsy instrument based on World Health Organization (WHO) standards. A cause list was constructed based on the WHO Global Burden of Disease estimates of the leading causes of death, potential to identify unique signs and symptoms, and the likely existence of sufficient medical technology to ascertain gold standard cases. Blinded verbal autopsies were collected on all gold standard deaths.ResultsOver 12,000 verbal autopsies on deaths with gold standard diagnoses were collected (7,836 adults, 2,075 children, 1,629 neonates, and 1,002 stillbirths). Difficulties in finding sufficient cases to meet gold standard criteria as well as problems with misclassification for certain causes meant that the target list of causes for analysis was reduced to 34 for adults, 21 for children, and 10 for neonates, excluding stillbirths. To ensure strict independence for the validation of methods and assessment of comparative performance, 500 test-train datasets were created from the universe of cases, covering a range of cause-specific compositions.ConclusionsThis unique, robust validation dataset will allow scholars to evaluate the performance of different verbal autopsy analytic methods as well as instrument design. This dataset can be used to inform the implementation of verbal autopsies to more reliably ascertain cause of death in national health information systems.

Highlights

Verbal autopsy methods are critically important for evaluating the leading causes of death in populations without adequate vital registration systems
Previously published validation studies compare the cause of death for individuals derived from verbal autopsy to the cause of death recorded in hospital records or that derived from independent review of hospital medical records
Validation studies often do not provide details on the exact items in the Verbal autopsy (VA) instrument, the training of interviewers, the training of physicians for physician-certified verbal autopsy (PCVA), the coding of death certificates completed by physicians for PCVA, or the protocol used to extract a cause of death from the hospital records

Summary

Introduction

Verbal autopsy methods are critically important for evaluating the leading causes of death in populations without adequate vital registration systems. New methods to analyze VAs and attribute causes of death to them are being developed [15,16,17,18,19], and it is likely that there will continue to be new methods and refinements Given both the increasing demand for good cause of death information for the world’s poorest populations and the expanding array of VA approaches, it is essential to be able to assess the performance of these options in a scientific and comparable manner. The quality of record keeping and the laboratory, medical imaging, and pathological services available in many developing country hospitals can be extremely poor This is especially true in resource-poor remote areas where validation studies have been undertaken. Validation studies often do not provide details on the exact items in the VA instrument, the training of interviewers, the training of physicians for PCVA, the coding of death certificates completed by physicians for PCVA, or the protocol used to extract a cause of death from the hospital records

Methods

Results

Conclusion