Basic Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Cardiol. Oct 26, 2019; 11(10): 244-255
Published online Oct 26, 2019. doi: 10.4330/wjc.v11.i10.244
Evaluating the quality of evidence for diagnosing ischemic heart disease from verbal autopsy in Indonesia
Wenrong Zhang, Yuslely Usman, Retno Widyastuti Iriawan, Merry Lusiana, Sha Sha, Matthew Kelly, Chalapati Rao
Wenrong Zhang, Sha Sha, Matthew Kelly, Chalapati Rao, Department of Global Heath, Research School of Population Health, Australian National University, Canberra, ACT 2602, Australia
Yuslely Usman, Retno Widyastuti Iriawan, Merry Lusiana, National Agency for Health Research and Development, Ministry of Health, Jakarta 10110, Indonesia
Author contributions: Zhang W collected the data, carried out data analysis and drafted the paper; Sha S collaborated on the study design and development of analysis methods; Kelly M and Rao C conceived the design of the study and contributed to drafting the paper; Usman Y, Iriawan RW and Lusiana M provided access to the data, and guided and assisted with data collection; All authors contributed to final editing of the paper.
Supported by the Department of Foreign Affairs and Trade, Australian Government, under the Government Partnership for Development program, No. 70856.
Institutional review board statement: This research was approved by the Australian National University Human Ethics Review board with protocol number 2018/493. It was also approved by the Indonesian National Agency for Health Research and Development ethics review board.
Institutional animal care and use committee statement: All procedures involving animals were reviewed and approved by the Institutional Animal Care and Use Committee of Australian National University.
Conflict-of-interest statement: The authors declare no conflicts of interest.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Wenrong Zhang, Doctor, Department of Global Heath, Research School of Population Health, Australian National University, 62 Mills Road, Canberra, ACT 2602, Australia. wenrong.zhang@anu.edu.au
Telephone: +61-2-61250714
Received: June 4, 2019
Peer-review started: June 6, 2019
First decision: July 30, 2019
Revised: August 29, 2015
Accepted: September 13, 2019
Article in press: September 13, 2019
Published online: October 26, 2019
Processing time: 242 Days and 7.5 Hours
ARTICLE HIGHLIGHTS
Research background

Mortality and cause of death data are the basis for health policy and research. The Civil Registration and Vital Statistics (CRVS) system is the ideal source of data, but the CRVS in Indonesia is still under development. Since 2014, the National Sample Registration System (SRS) has provided nationally representative mortality data from 128 sub-districts. Verbal autopsy (VA) is used in SRS to obtain the cause of death.

Research motivation

The evidence available from the VA to diagnose causes of death must be assessed to establish the reliability and utility of SRS data. The diagnosis of VA may be influenced by many factors, such as questionnaire design, interviewer skills, characteristics of respondents (including proximity to the deceased), recall period for interviews, and methods for determining the cause of death. Given these potential sources of bias, the World Health Organization recommends conducting scientific research to assess the quality of VA’s cause of death, hence necessitating this study.

Research objectives

This study was designed to assess the quality of evidence used to diagnose Ischaemic Heart Disease (IHD) as a cause of death from VA. The study also sought to evaluate various factors that could influence the quality of evidence, such as age and gender of the deceased, place of death, relationship of the respondent, and recall period.

Research methods

The study sample comprised a random sample of 400 deaths out of a total of 4,070 cases diagnosed from IHD in the SRS data for 2016. A data extraction form and data entry template were designed to collect relevant IHD data from VA questionnaires. A standardised classification was designed to IHD cases to categories with strong, medium and weak evidence. Strong evidence of IHD was defined to include surgery for coronary heart disease, or the history of chest pain along with two additional characteristics among sudden death; history of heart disease; the medical diagnosis of heart disease; or terminal shortness of breath. Statistical analysis was conducted to assess the frequency of cases with different levels of evidence, as well as to identify associations between case characteristics and levels of evidence.

Research results

Nearly half of all IHD deaths were concentrated in the 50-69 age group (48.40%), and another 36.10% were 70-years-old or older. Two-thirds of the deceased were male (58.40%). VA questionnaires for about three-quarters of all cases contained strong or medium evidence to diagnose IHD. Quality of evidence was significantly associated with the occurrence of deaths in hospitals, with male deaths at home, and with deaths for which the respondent belonged to the same generation as the deceased.

Research conclusions

VA diagnoses of IHD was found to be based on acceptable evidence in the majority of cases in the study sample. Attention is required to improve recording of information during VA interviews, particularly in regard to correct interpretation of responses for symptoms and signs, and more importantly, clinical details from interactions with health services. Such studies should be conducted for other leading causes of death in Indonesia, as well as across space and time.

Research perspectives

The study assessed levels and determinants of the quality of diagnostic evidence to assign Ischaemic Heart Disease as a cause of death from VA methods in Indonesia. The study results provided perspectives on VA data collection processes, evidence patterns guiding VA diagnosis, and the influence of various circumstances of the death event and household interview on the overall quality of evidence from VA.