Table 1 General description of the Health Interview Survey (HIS) and the Survey on Income and Living Conditions (SILC), Belgium
From: Using mortality follow-up of surveys to estimate social inequalities in healthy life years
Criteria | HIS | SILC |
|---|---|---|
Aim of the survey | To describe the health status of the population and monitor health trends in Belgium and its three regions. | To provide a complete set of indicators on poverty, social exclusion, pensions, and material deprivation. |
Health indicators | A wide series of health indicators, including the Global Activity Limitation Indicator (GALI) used to estimate HLY. | Three generic health indicators including the Global Activity Limitation Indicator (GALI). |
Socio-economic status indictors | Education, income, employment. | Education, income, employment. |
Mortality follow-up | Linkage with mortality data of the National Register using a unique identifier is possible after privacy commission approval. | Linkage with mortality data of the National Register using a unique identifier is possible after privacy commission approval. |
Survey design | Stratified multistage clustered scheme. | Stratified two-stage sampling scheme in 2004, followed by rotation since 2005. Rotation allows to replace roughly one-fourth of the sample each year. The rotation pattern is such that the overlap between samples in any two successive years is roughly 75%, and that the sample is completely renewed after four years. |
The sample is representative at the national and regional levels. | The sample is representative at the national level. | |
Sample size | Approximately 10,000 individuals, although in some years the sample is bigger due to an oversampling of some age groups or municipalities. | Approximately 9,000 individuals . |
Target population | All individuals residing in Belgium at the time of data collection. The GALI used to estimate HLY is included in the self-completed questionnaire that is given only to those aged 15 years and older. | All individuals residing in Belgium at the time of data collection aged 16 years and older. |
Response rate | For 2008, the household response rate was about 55%. | For 2010, the household response rate was 43.3% for new households (households drawn for the first time in 2010) and 63.5% when accounting for the new and old households (households that contain at least one person who took part in 2009 and had to be surveyed again in 2010 according to the rotation design). |
Periodicity | Every three to five years. | Annual. |