As the name implies, the Sleman HDSS’ working area is in Sleman Regency, Special Region of Yogyakarta (DIY). Sleman Regency was chosen because of the following reasons:

• Sleman Regency comprises urban, suburban, and rural areas. Therefore, Sleman HDSS’ data can capture variation in the disease prevalence and risk factors in each of those areas.
• Sleman Regency has a high life expectancy compared to other regencies in Indonesia. Thus, issues related to healthy aging are something that urgently needs attention. A reliable and valid information regarding aging population is essential in developing proper interventions to promote healthy aging.
• The Universitas Gadjah Mada campus is located in Sleman Regency, making communication between Sleman HDSS team and the Sleman Government, data collection, and community engagement are easier to manage.

Sleman Regency located at coordinates 110 ° 33 ′ 00 ″ and 110 ° 13 ′ 00 ″ East Longitude, 7 ° 34 ′ 51 ″ and 7 ° 47 ′ 30 ″ South Latitude and is bordered by the other regencies, i.e.:

North : Boyolali Regency
East    : Klaten Regency
South : Bantul Regency and Yogyakarta City
West : Kulon Progo Regency and Magelang Regency

The area of ​​Sleman Regency is 574.82 km2, comprising 17 districts and 86 villages. Based on BPS (Badan Pusat Statistik– Statistics Indonesia) in 2012, the total number of Sleman Regency population reached 1,107,187 people with a gender ratio of 98.84 and a population density of 1,939 people / km2. The total number of households was 315,445, with an average household size of 3.29 people/household.

In the first wave of data collection, the HDSS Sleman collected data from 5,147 households in 216 selected clusters in 80 villages. Of all these clusters, 184 clusters are in urban areas and 32 clusters are in rural areas. Figure 1 shows areas in which data collection was conducted.