About CDHS

1  Geodemography, History, and Economy



Cambodia is an agricultural country located in Southeast Asia. It is bounded by Thailand to the west, Laos and Thailand to the north, the gulf of Thailand to the southwest, and Vietnam to the east. It has a total land area of 181,035 square kilometers.Cambodia has a tropical climate with two distinct monsoon seasons, which set the rhythm of rural life. From November to February, the cool, dry northeastern monsoon brings little rain, whereas the southwestern monsoon carries strong winds, high humidity, and heavy rains. The mean annual temperature for Phnom Penh, the capital city, is 27°C. The 1962 census was the last official census to be conducted prior to 1998; it revealed a population of 5.7 million. The population census in 1998 recorded the number of the people in the country at 11,437,656 with an annual growth rate of 2.5 percent (National Institute of Statistics, 1999). The 2004 Inter-Censal Population Survey showed that the annual growth rate declined from 2.5 percent in 1998 to 1.81 percent in 2004, with the total population of 13.09 million (National Institute of Statistics, 2004). A large proportion of the population, 85 percent, live in rural areas, and only 15 percent live in urban areas. The population density in the country as a whole is 74 per square kilometer. More than a million inhabitants (1.044 millions) are living in Phnom Penh. The average size of the Cambodian household is 5.1. The total male to female sex ratio is 93.5. The literacy rate among adults age 15 and over is 73.6 percent. The male adult literacy rate (84.7 percent) is considerably higher than the rate of females (64.1 percent). Currently, it is estimated that approximately 34.7 percent of the total population lives below the poverty line.


Cambodia gained complete independence from France under the leadership of Prince Norodom Sihanouk on 9 November 1953. In March 1970, a military coup led by General Lon Nol overthrew Prince Sihanouk. On 17 April 1975, the Khmer Rouge ousted the Lon Nol regime and took control of the country. Under the new regime, the country was renamed Democratic Kampuchea. Nearly three million Cambodian people died during the Khmer Rouge’s radical and genocidal regime. On 7 January 1979, the revolutionary army of the National Front for Solidarity and Liberation of Cambodia defeated the Khmer Rouge regime and proclaimed the country the People’s Republic of Kampuchea and later in 1989 as the State of Cambodia. The most important political event was the free elections held in May 1993 under the close supervision of the United Nations Transitional Authority in Cambodia (UNTAC). Since then, Cambodia was proclaimed the Kingdom of Cambodia and has a system of constitutional monarchy. Another two free and fair elections took place in 1998 and 2003. Now, Cambodia is stable and well on its way to democracy and a promising future.


Since the 1991 Paris Peace Accord, Cambodia’s economy has made significant progress after more than two decades of political unrest. However, Cambodia still remains the poorest and least developed country in Asia, with the gross domestic product per capita estimated at approximately 1,400,000 Riel or $339 in 2005 (US$1= 4,128 Riel) (Ministry of Health, 2006). Agriculture, mainly rice production, is still the main economic activity for Cambodia. In addition, small-scale subsistence agriculture, such as fisheries, forestry, and livestock, are still the most important sector. In addition, garments factories and tourism services are also important components of foreign direct investment.


Health outcomes have been improved recently. The infant mortality rate has decreased from 95 per 1,000 live births in 2000 to 66 in 2005 and the under-five mortality rate from 124 to 83 in the same period. Life expectancy at birth is 58 for male and 64 for female (Ministry of Planning, 2006). The government expenditure on health per capita is $4.09 (Ministry of Health, 2006). Despite progress made, the health status of the Cambodian people is still among the lowest in the region. To improve the health status of the Cambodian people, the Ministry of Health developed the Health Sector Strategic Plan for 2003-2007 (Ministry of Health, 2002). Its policy statement follows:
    • Implement sector-wide management through a common vision and effective partnerships among all stakeholders;
    • Provision of basic health services to the people of Cambodia with the full involvement of the community;
    • Provision of affordable, essential specialized hospital services;
    • Decentralization and de-concentration of financial, planning and administrative functions within the health sector;
    • Priority emphasis on prevention and control of communicable and selected chronic and non-communicable diseases, on injury, the elderly, adolescents and vulnerable
      groups such as the poor, and on managing public health crises;
    • Priority emphasis on provision of good quality care to mother and child especially essential obstetric and pediatric care;
    • Active promotion of healthy lifestyles and health-seeking behavior among the population;
    • Emphasis on quality, effective and efficient provision of health services by all health providers;
    • Optimization of human resources through appropriate planning, management including deployment and capacity development within the health system;
    • Increase promotion of effective public and private partnerships for effective and efficient basic and specialist care;
    • Effective use of the health information for evidence-based planning, implementation, monitoring and evaluation in the health sector;
    • Implementation of health financing systems to promote equitable access to priority services especially by the poor; and
    • Further development of appropriate health legislation to protect the health of providers and consumers.


The 2005 Cambodia Demographic and Health Survey (CDHS) is the second nationally representative survey conducted in Cambodia on population and health issues. It uses the same methodology as its predecessor, the 2000 Cambodia Demographic and Health Survey, allowing policymakers to use the two surveys to assess trends over time. The primary objective of the CDHS is to provide the Ministry of Health, Ministry of Planning (MOP), and other relevant institutions and users with updated and reliable data on infant and child mortality, fertility preferences, family planning behavior, maternal mortality, utilization of maternal and child health services, health expenditures, women’s status, domestic violence, and knowledge and behavior regarding HIV/AIDS and other sexually transmitted infections. This information contributes to policy decisions, planning, monitoring, and program evaluation for the development of Cambodia, at both national- and local-government levels. The long-term objectives of the survey are to technically strengthen the capacity of the National Institute of Public Health (NIPH), Ministry of Health, and the National Institute of Statistics (NIS) of MOP for planning, conducting, and analyzing the results of further surveys. The 2005 DHS survey was conducted by the National Institute of Public Health (NIPH), the Ministry of Health, and the National Institute of Statistics of the Ministry of Planning. The CDHS executive committee and technical committee were established to oversee all technical aspects of implementation. They consisted of representatives from the Ministry of Health, the National Institute of Public Health, Department of Planning and Health Information, the Ministry of Planning, the National Institute of Statistics, the U.S. Agency for International Development (USAID), Department for International Development (DFID), the United Nations Population Fund (UNFPA), and the United Nations Children’s Fund (UNICEF). Funding for the survey came from USAID, the Asian Development Bank (ADB) (under the Health Sector Support Project HSSP, using a grant from the United Kingdom, DFID), UNFPA, UNICEF, and the Centers for Disease Control/Global AIDS Program (CDC/GAP). Technical assistance was provided by ORC Macro.


Creation of the 2005 CDHS sample was based on the objective of collecting a nationally representative sample of completed interviews with women and men between the ages of 15 and 49. To achieve a balance between the ability to provide estimates for all 24 provinces in the country and limiting the sample size, 19 sampling domains were defined, 14 of which correspond to individual provinces and 5 of which correspond to grouped provinces.
    • Fourteen individual provinces: Banteay Mean Chey, Kampong Cham, Kampong Chhnang, Kampong Speu, Kampong Thom, Kandal, Kratie, Phnom Penh, Prey Veng,
      Pursat, Siem Reap, Svay Rieng, Takeo, and Otdar Mean Chey;
    • Five groups of provinces: Battambang and Krong Pailin, Kampot and Krong Kep, Krong Preah Sihanouk and Kaoh Kong, Preah Vihear and Steung Treng, Mondol Kiri,
      and Rattanak Kiri.
The sample of households was allocated to the sampling domains in such a way that estimates of indicators can be produced with known precision for each of the 19 sampling domains, for all of Cambodia combined, and separately for urban and rural areas of the country.

 The sampling frame used for 2005 CDHS is the complete list of all villages enumerated in the 1998 Cambodia General Population Census (GPC) plus 166 villages which were not enumerated during the 1998 GPC, provided by the National Institute of Statistics (NIS). It includes the entire country and consists of 13,505 villages. The GPC also  created maps that delimited the boundaries of every village. Of the total villages, 1,312 villages are designated as urban and 12,193 villages are designated as rural, with an average household size of 161 households per village.

The survey is based on a stratified sample selected in two stages. Stratification was achieved by separating every reporting domain into urban and rural areas. Thus the 19 domains were stratified into a total of 38 sampling strata. Samples were selected independently in every stratum, by a two stage selection. Implicit stratifications were achieved at each of the lower geographical or administrative levels by sorting the sampling frame according to the geographical/administrative order and by using a probability proportional to size selection at the first stage of selection.


Three questionnaires were used: the Household Questionnaire, Woman Questionnaire, and Man Questionnaire. The content of these questionnaires was based on model questionnaires developed by the MEASURE DHS project. Technical meetings between experts and representatives of the Cambodian government and national and international organizations were held to discuss the content of the questionnaires. Inputs generated by these meetings were used to modify the model questionnaires to reflect the needs of users and relevant population, family planning, and health issues in Cambodia. Final questionnaires were translated from English to Khmer and a great deal of refinement to the translation was accomplished during the pretest of the questionnaires. The Household Questionnaire served multiple purposes:
    • It was used to list all of the usual members and visitors in the selected households and was the vehicle for identifying women and men who were eligible for the individual interview.
    • It collected basic information on the characteristics of each person listed, including age, sex, education, and relationship to the head of the household.
    • It collected information on characteristics of the household’s dwelling unit, ownership of various durable goods, ownership and use of mosquito nets, and testing of salt for iodine content.
    • It collected anthropometric (height and weight) measurements and hemoglobin levels.
    • It was used to register people eligible for collection of samples for later HIV testing.
    • It had a module on recent illness or death.
    • It had a module on utilization of health services.

The Women’s Questionnaire covered a wide variety of topics divided into 13 sections:
    • Respondent Background
    • Reproduction, including an abortion module
    • Family Planning
    • Pregnancy Postnatal Care and Children’s Nutrition
    • Immunization Health and Women’s Nutrition
    • Cause of Death of Children (also known as Verbal Autopsy)
    • Marriage and Sexual Activity
    • Fertility Preferences
    • Husband’s Background and Woman’s Work
    • HIV AIDS and Other Sexually Transmitted Infections
    • Adult and Maternal Mortality
    • Women’s Status
    • Household Relations (also known as Domestic Violence)

The Men’s Questionnaire was administered to all men age 15-49 years living in every second household of the 2005 CDHS sample. The Man Questionnaire collected information similar to that of the Woman Questionnaire but was shorter as it did not contain as detailed a reproductive history, or questions on maternal and child health, or nutrition.


The goal of training was to create 19 field teams capable of collecting data for the CDHS 2005. Each team was responsible for data collection in one of the 19 survey domains (comprised of the 24 provinces). Field teams were each composed of 6 people: team leader, field editor, three female interviewers, and one male interviewer. After three weeks of training on questionnaires, data entry staff had acquired the necessary knowledge of the survey instruments and were released from training. The 122 field personnel continued on for three more weeks of training: one week for blood training, one week on miscellaneous topics, and one week of field practice.

The first week of training was devoted to the Household Questionnaire. The next two weeks were devoted to 13 Sections of the Woman Questionnaire. Additional time was spent reviewing the Household Questionnaire, including the selection of women for the Household Relations Module, Consent Statements for blood collection, and conversion of ages and dates of birth between the Khmer and Gregorian calendar.

One week was devoted to additional activities: the Man Questionnaire, measuring height and weight of women and children, sample implementation and household selection (logistically complicated and required two days of training), collection of Geographic Positioning System data, testing of household salt for iodine, organization of documents and materials for return to the head office.

One week of main survey training was devoted to the collection of blood samples. All interviewers were designated to collect blood samples in the field, thus all interviewers were trained for blood collection procedures. While field editors and supervisors were not designated to collect blood samples in the field, they also underwent blood collection training so that all team members were fully aware of all responsibilities related to the collection of blood samples. Complete understanding of all survey activities by all team members contributed greatly to the maintenance of high data quality standards over a long period of data collection.

Training in the collection of blood samples included procedures for: identifying the correct household eligible for HIV testing in the 50 percent subsample; identifying men and women within those households eligible for HIV testing; obtaining voluntary consent of respondents; safety procedures in handling blood samples; techniques in capillary blood draw; use of the HemoCue machine for field testing of hemoglobin levels to assess levels of anemia; capturing blood samples for anemia testing; capturing blood samples for laboratory testing of HIV; providing referral for respondents needing treatment for anemia; providing vouchers for VCT services; providing HIV information pamphlets; rendering the blood sample for HIV anonymous; proper storage of dried blood spots in the field; packaging of dried blood spots for transport to the laboratory; disposal of biohazardous waste; and recording information in the questionnaires.

The five weeks of training were followed by a full week of field practice. Two supplementary days prior to launching fieldwork were required to cover fieldwork control forms, and supply teams with all necessary equipment. Each interviewer needs over 50 distinct items to perform a complete interview. Fieldwork was then launched, and teams disbursed to their assigned provinces.

During the training period, the 19 CDHS team leaders were provided with the cluster information for the provinces in which they would be working in order to devise a data collection sequence for their sample points. They were best equipped to perform this task as team leaders hailed from their own provinces. They also conducted the CDHS Household Listing operation (described in sample design) and therefore were well-acquainted with the areas in which they would have to work.

The progression of fieldwork by geographic location had to take into account weather conditions during rainy season. A fieldwork supervision plan was created for the six CDHS survey coordinators from NIS and NIPH and ORC Macro to conduct regular field supervision visits. Supervision visits were conducted throughout the six months of data collection and included the retrieval of questionnaires and blood samples from the field. In addition, a quality control program was run by the data processing team to detect key data collections errors for each team. Based on these data checks, regular feedback was given to each team based on their specific performance.

Data collection was conducted from 9 September 2005 to 7 March 2006.


Data entry on 19 personal computers began on 22 September 2005, just two weeks after the first interviews were being conducted. Data entry personnel attended questionnaire training of interviewers so as to become familiar with the survey instruments. Data processing personnel included a data processing chief, four assistants, 19 entry operators, and three office editors. Completed questionnaires were brought in from the field by survey coordinators and questionnaires and anonymous blood samples were logged by the office editors. Once proper accounting of questionnaires and blood samples was accomplished on a per-cluster basis, blood samples were transported to the NIPH laboratory for later testing. Questionnaire data were entered at NIS using CSPro, a program developed jointly by the United States Census Bureau, the ORC Macro MEASURE DHS program, and Serpro S.A. All questionnaires were entered twice to minimize data entry error. Data entry was completed in April 2006. Internal consistency verification and secondary editing were completed in May 2005.


All of the 557 clusters selected for the sample were surveyed in the 2005 CDHS. A total of 15,046 households were selected, of which 14,534 were identified and occupied at the time of the survey. Among these households, 14,243 completed the Household Questionnaire, yielding a response rate of 98 percent (Table 1.1). In the 14,243 households surveyed, 17,256 women age 15-49 years were identified as being eligible for the individual interview. Interviews were completed with 16,823 of these women, yielding a response rate of 98 percent. Interviews with men were conducted in every second household. A total of 7,229 men age 15-49 years were identified in the subsample of households. Of these 7,229 men, 6,731 completed the individual interview, yielding a response rate of 93 percent.