Verbal autopsy in Karachi slums: comparing single and multiple cause of child deaths

Abstract

Background: Children dying in developing countries often have more than one serious disease process. Identifying the single most important is difficult and risks omitting valuable information. We report patterns of childhood death in Karachi slums comparing single and multiple cause analysis. Methods: The Aga Khan University has developed primary health care programmes in Karachi slums where community health workers maintain monthly surveillance of families with children aged under five years. We investigated all deaths among children under five from 1990 to 1992 when the overall IMR was 78. We used a structured verbal autopsy questionnaire comprised of verbatim and symptom check-list sections. Reviewers assigned up to four diagnoses per death. We compared analysis by single (main) cause and multiple (consolidated) causes per case. Results: Overall, the 431 cases had 627 causes of death; 156 cases (36%) had more than one cause of death. By consolidated analysis, diarrhoea, malnutrition, low birth weight (LBW), acute respiratory infection (ARI), and vaccine preventable diseases played roles in 41%, 24%, 22%, 13%, and 2% of deaths, respectively. Proportionate mortality ratios by main cause (1 diagnosis per child) analysis for the same diagnoses were: 39%, 1%, 8%, 11%, and 1%, respectively. Half of all child death occurred by age 3 months. Eighty-three per cent (146/176) of fatal diarrhoea syndromes were due to acute watery diarrhoea, and 41% (72/176) were associated with severe malnutrition (vs 21% [12/56] of fatal ARI cases). Each verbal autopsy cost an estimated US$4.00, an annual cost of US$0.08 per programme child. Implications: Compared to single main cause analysis, consolidated analysis more completely assesses reasons for child death to guide programme response. We propose that health planning for populations with low vaccine coverage or common co-morbid conditions, such as malaria and anaemia, would particularly benefit from analysis of death seeking multiple causes.