BMC Public Health 2005, 5:58 http://www.biomedcentral.com/1471-2458/5/58 illness, obtained from the family of the deceased, to assign cause of death. VA data are generated through retrospec- tive questioning in surveys or in demographic surveillance systems [3-6]. The VA technique is based on the assumption that most causes of death have distinct symptom complexes that can be recognized, remembered and reported by lay respond- ents. It assumes that it is possible to classify deaths based on the reported information into useful categories of causes of death. The validity of VA is influenced by the type of illness leading to death, characteristics of the deceased person, and other factors related to the classifi- cation of causes of death, as well as the design and content of the questionnaire and field procedures [5,7,8]. Factors that affect the validity of a VA include the approach to mortality classification, the design of the questionnaire, the methods of deriving a diagnosis, and the number and combinations of categories of causes of death assigned. The choice of categories of causes of death determines the complexity of diagnostic algorithms. A classification approach using fewer categories will group causes of death with closely related symptom complexes together and hence tends to increase the validity of the VA but provides less detailed information. The other advan- tage in broadly classifying mortality is that the classifica- tion can be used in a wide range of settings with minor modifications [5]. The type of questionnaire also influences the validity of the VA outcome. An open format VA questionnaire would require skilled and possibly medically trained interview- ers, and would also have a higher inter-interviewer varia- bility. A checklist with filters on the other hand would not need medically trained interviewers, and would be more efficient for data collection. But, a false negative answer to a filter question will result in omitting one whole disease category and hence decrease the sensitivity of the VA. A checklist without filters would not require a medically trained person and would reduce interviewer bias, but it may not capture all details of the symptoms leading to death and may increase the number of falsely reported symptoms [5]. Different validation studies for the VA method have been done for deaths in children [9-12], and adults [6,13] sug- gesting that the VA method is an important tool for diag- nosing causes of death, especially in developing countries. Studies in Tanzania [14] and in Ethiopia [15] have shown the robustness of VA method in identifying cause of death using lay interviewers. Trends in cause-specific mortality over time, differentials of mortality between different population groups, or eval- uation of the effect of interventions can be studied from data using the VA method. Additionally, they can be used to establish the relative public health importance of differ- ent causes of death in the populations in order to identify priorities and appropriate interventions [5,16] Ethiopia is a country where low standards of living, poor environmental conditions and under developed social services have caused serious impact on the health status of the population [17,18]. Although adults are the pillar of the society as economically productive, biologically repro- ductive, and responsible for the support of children and elderly dependents their health needs receive little atten- tion in developing countries [19]. Information on adult health conditions is essentially non-existent in most developing countries as the routine system does not cover large segment of the population, especially those living in the rural areas [2,20,21]. In Ethiopia, due to the absence of vital event registration system and inaccessibility of health facilities most deaths occur at home and pass undocumented. This study was done with the objective of identifying the causes of death in a predominantly rural population where almost all deaths are occurring at home. The paper tries to demonstrate a possibility of using a relatively simple and inexpensive verbal autopsy method for obtaining valuable data in improving health services to the rural underserved populations. Methods The study district, Meskan and Mareko, is located in the central-south part of Ethiopia at an average altitude of 2,100 meters above sea level with a range of 1,750 m in the low lands to 3,400 m in the mountainous areas. The actual study sites were the nine rural and one urban study kebeles (Kebele is the smallest administrative unit in Ethio- pia often having an average of 500 households, the size varies significantly from district to district) that are under continuous demographic surveillance by the Butajira Rural Health Program (BRHP). These sites were randomly selected using the probability proportionate to size tech- nique. The BRHP registers events such as birth, death, marriage, new household, out-migration, in-migration, and internal move. Information on the circumstances leading to death was not routinely collected by the surveil- lance system. Data on mortality as well as the above men- tioned events were collected monthly, by trained village- based enumerators, through household visits. The total population of the area was estimated to be 257,000 in 1999. Detailed description of the study area is given else- where [22]. All adult deaths in the age group 15 to 49 year that were registered by the BRHP from January 1995 to December 1999 were identified from the longitudinal surveillance database and considered for this study. The age-group 15– Page 2 of 7 (page number not for citation purposes)