What does the survey comprise?
To give an overview of the developments in health, medical contacts, lifestyle and preventive behaviour of the Dutch population.
For most subjects, persons aged 0 years or older living in private households. For some subjects other age limits apply.
Year survey started
Statistics Netherlands has been conducting an annual health survey since 1981. In the period 1997-2009 the Health Survey was a module of the Continuous Survey on Living Conditions. Since 2010 the Health Survey is an independent survey again.
The figures are definite.
How is the survey conducted?
Sample of persons. The sample is spread over all months of the year.
Since 2010, the Health Survey is conducted in a new ‘mixed mode’ design. Sample units (persons) are asked to participate via the internet (CAWI – Computer Assisted Web Interviewing). Non-respondents are re-approached using Computer Assisted Telephone Interviewing (CATI) if their telephone number is known, and otherwise by way of Computer Assisted Personal Interviewing (CAPI).
An additional questionnaire is used for respondents aged 12 years or older, focusing among other things on potentially sensitive items. Response to this additional part can be provided online or on paper.
Persons living in private households.
Since 2010, the annual net sample size is approximately 15,000 persons. The response rate is about 60-65 percent; around 55 percent of these respondents also respond to the additional questionnaire for persons aged 12 years or older.
Checking and correction methods
Internal consistency and completeness is regularly checked every year.
A correction is applied to control for differences between the sample and the population. For this purpose a weighting factor is used based on sex, age, ethnic background, marital status, degree of urbanisation, geographical features, household size and survey period. Additional weighting factors are used for response to the additional questionnaire: smoking status, level of education and chronic morbidity/limitations.
Quality of the results
As the survey is based on a sample, the results will fluctuate because of random errors. The standard errors of the figures are shown in the StatLine tables. Figures are not shown if the number of respondents in a classification category is lower than 50, because in that case the standard errors are considered to be too large.
Generally speaking figures for 2010 are comparable with those for 2009. The transition to mixed mode observation in 2010, however, has led to some breaks in series. Furthermore the survey questions about medical consumption have been revised in 2010. This may also have caused breaks in series. Therefore caution should be exercised when comparing figures for 2010 with those for previous years.