Cause-specific mortality patterns among hospital deaths in Thailand: validating routine death certification

Abstract

BackgroundIn Thailand, 35% of all deaths occur in hospitals, and the cause of death is medically certified by attending physicians. About 15% of hospital deaths are registered with nonspecific diagnoses, despite the potential for greater accuracy using information available from medical records. Further, issues arising from transcription of diagnoses from Thai to English at registration create uncertainty about the accuracy of registration data even for specified causes of death. This paper reports findings from a study to measure validity of registered diagnoses in a sample of deaths that occurred in hospitals in Thailand during 2005.MethodsA sample of 4,644 hospital deaths was selected, and for each case, medical records were reviewed. A process of medical record abstraction, expert physician review, and independent adjudication for the selection and coding of underlying causes of death was used to derive reference diagnoses. Validation characteristics were computed for leading causes of hospital deaths from registration data, and misclassification patterns were identified for registration diagnoses. Study findings were used to estimate cause-specific mortality patterns for hospital deaths in Thailand.ResultsAdequate medical records were available for 3,316 deaths in the study sample. Losses to follow up were nondifferential by age, sex, and cause. Medical records review identified specific underlying causes for the majority of deaths that were originally assigned ill-defined causes as well as for those originally assigned to residual categories for specific cause groups. In comparison with registration data for the sample, we found an increase in the relative proportion of deaths in hospitals due to stroke, ischemic heart disease, transport accidents, HIV/AIDS, diabetes, liver diseases, and chronic obstructive pulmonary disease.ConclusionsRegistration data on causes for deaths occurring in hospitals require periodic validation prior to their use for epidemiological research or public health policy. Procedures for death certification and coding of underlying causes of death need to be streamlined to improve reliability of registration data. Estimates of cause-specific mortality from this research will inform burden of disease estimation and guide interventions to reduce avoidable mortality in hospitals in Thailand.

Correcting and estimating HIV mortality in Thailand based on 2005 verbal autopsy data focusing on demographic factors, 1996-2009

“…The specificity level from our model was higher than a verbal autopsy tool from Uganda, where sensitivity was not reported [45]. The cross-referencing method has been used in many previous studies [1,[15][16][17][18]45]. Inadequate models can give misleading or incorrect inferences [26].…”

“…The latest VA study in Thailand was carried out in 2005 in nine provinces by the SPICE (Setting Priorities using Information on Cost-Effectiveness analysis) project. The 2005 VA study [8,[16][17][18] was used to estimate various causes of death including HIV. However, the simple cross-referencing method used in these studies ignored the effect of sex-age groups and locality of the deceased, which could give incorrect estimates due to confounding.…”

Availability and quality of vital registration mortality data in South Africa: a national and surveillance site perspective

“…Substantial misclassification occurred to conditions such as cardiac and cerebrovascular disease, and diabetes was mentioned on only 71% of death certificates. 231 Findings of unreliable diabetes diagnoses on civil registration death certificates were also reported by Pattaraarchachai et al 232 in Thailand, finding about six times fewer deaths from diabetes as a registered underlying cause among Thai hospital deaths, compared to the number of deaths with diabetes that were ascertained via medical record review. 232 For non-hospital deaths in Thailand too, Polprasert et al found that diabetes was under-recorded as an underlying cause of death in civil registration data compared to verbal autopsy data.…”

“…Against this background, and considering the successful work done in Thailand, 232,292 a nationally representative validation study of CRVS cause-of-death data from hospital deaths against reference diagnoses derived from post-mortem physical autopsy reports or good-quality medical records, is recommended.…”

“…278 In contrast, in an earlier study, the sensitivity of the death certificate to identify cancer deaths in the same city was 57% for 1992 and 1993 deaths. 291 The value of a verbal autopsy approach is shown in both hospital and out-of-hospital deaths in a cause-of-death study in Thailand 292 where verbal autopsy diagnoses first were validated against reference diagnoses from a medical record review for in-hospital deaths, 232 and the validated study findings then were used to adjust the causes of death which were derived from verbal autopsies for out-of-hospital deaths. 233 The authors concluded that verbal autopsy methods adapted to local use in Thailand enabled a substantial reduction of ill-defined diagnoses in registered deaths; a plausible assessment of cause-specific mortality patterns; and that routine incorporation of verbal autopsy methods could significantly improve the quality of cause-of-death data in Thailand.…”