ANNEX I. >> M  etadata sheets on selected indicators Survey results may be unreliable where the sample size is too small or incorrectly designed for the target population, where insensitive or inconsistent questioning methodology is used, or where surveys of the entire population are used to draw conclusions for particularly vulnerable groups. Such groups are less likely to respond to surveys, so specifically targeted surveys with special sampling methodologies are required for each vulnerable group. Examples of references of relevance to the right to a fair trial: Universal Declaration of Human Rights, arts. 10 and 11; International Covenant on Civil and Political Rights, arts. 14 and 15; International Convention on the Elimination of All Forms of Racial Discrimination, art. 5 (a); Convention on the Elimination of All Forms of Discrimination against Women, art. 2; Convention on the Rights of the Child, arts. 12 (2), 37 (d) and 40; International Convention on the Protection of the Rights of All Migrant Workers and Members of Their Families, arts. 16 (5)–(9) and 18; and Convention on the Rights of Persons with Disabilities, art. 13. Indicator 9 Proportion of births attended by skilled health personnel [e.g., table on the right to enjoyment of the highest attainable standard of physical and mental health] Definition  The indicator refers to the proportion of childbirths attended by skilled health personnel trained to give necessary supervision, care and counsel to women during pregnancy, labour and the postpartum period; to conduct deliveries on their own; and to care for newborns. Rationale  The health and the well-being of the woman and the child during and after delivery greatly depend on their access to obstetric services, the quality of these services and the actual circumstances of the delivery. All of these are influenced by the State’s health policies, the public provision of health services and the regulation of private health care. Indeed, the availability of professional and skilled health personnel with adequate equipment to assist in childbirth is essential for reducing mortality—maternal as well as of the child—during and after delivery. The indicator captures efforts by the State to promote and provide professional and skilled health personnel to attend to the medical needs of pregnancy and birth. It is a process indicator related to the “sexual and reproductive health” attribute of the right to health. Method of computation  The indicator is computed as the ratio of births attended by skilled health personnel (doctors, nurses or midwives) to the total number of deliveries. Data collection and source  The main sources of data are administrative records maintained by local authorities, registration systems for population data, records of health ministries and household surveys, including Demographic and Health Surveys. The World Health Organization (WHO) and the United Nations Population Fund (UNFPA) compile country data series based on these sources. The United Nations Children’s Fund (UNICEF) also provides country data series through the implementation of its Multiple Indicator Cluster Survey (MICS). Periodicity  In general, the indicator based on administrative records is available annually and the indicator based on household surveys every three to five years. Disaggregation  Disaggregation of the indicator by age (at least for women under the age of 18), economic and social situation, ethnicity, minority, indigenous, colour, language, religion, national or social origin, migrant, disability, marital and family status, place of residence, region and rural/urban, is useful in assessing disparities in the availability of health services. 154 Human Rights Indicators