Scottish Health Survey
Organisation responsible: The Scottish Health Survey (SHeS) is commissioned by the Scottish Government Health Department and is carried out by the Scottish Centre for Social Research (ScotCen), in collaboration with the Department of Epidemiology and Public Health at University College London (UCL) and the MRC Social and Public Health Sciences Unit at the University of Glasgow.
Background and purpose: The SHeS was introduced in 1995 to provide a detailed picture of the health of the Scottish population in private households and is designed to make a major contribution to the monitoring of health in Scotland. This information is essential for the Scottish Government's forward planning, for identifying gaps in health service provision and for identifying which groups are at particular risk of future ill-health. Specifically the SHeS aims to:
- estimate the prevalence of particular health conditions in Scotland;
- estimate the prevalence of certain risk factors associated with these health conditions and to document the pattern of related health behaviours;
- look at differences between regions and between subgroups of the population in the extent of their having these particular health conditions or risk factors, and to make comparisons with other national statistics for Scotland and England;
- monitor trends in the population's health over time;
- make a major contribution to monitoring progress towards health targets.
Survey years / frequency: One-off surveys were carried out in 1995, 1998 and 2003. Following redesign in 2007, the survey moved to a continuous format with annual reporting. The first continuous survey cycle ran from 2008-2011 with the current cycle running from 2012-2015.
Survey content: Until 2012, the survey used a two-stage interview process: a personal interview carried out by a trained interviewer followed by a nurse visit involving a series of anthropometric and biomedical measurements, including waist and hip circumference, blood pressure, lung function, blood, urine and saliva samples. Prior to 2008, the follow-up nurse visit was offered to all respondents, in 2008-11 it was offered to around one sixth of the adult sample. There was no nurse visit in 2012-15; most of the biological measurements were moved to the main interview, but this was not possible for venous blood samples. No blood samples were collected in 2012 but dry blood spot measurements via finger prick tests were introduced from 2013 onwards.
The survey moved to a core and modular structure from 2008. Core questions are asked every year and go to the whole sample. A rotating (biennial) module goes to a proportion of the sample - most of these questions are asked every second year although some are asked annually.
In 2008-11, NHS Health Scotland funded a second module containing questions on health-related knowledge, attitudes and motivations to health, the Knowledge, Attitudes and Motivations to Health module (KAM), to replace the previous Health Education Population Survey. The KAM module was discontinued due to restricted budgets, low response rate and the fact that there has been little change in behaviour over the combined HEPS and KAM time series (1996-2011) despite improvements in knowledge, attitudes and motivations, thus calling into question the model that the survey is based upon (Prochaska and DeClemente's Transtheoretical Model of Behaviour Change). The final KAM report was published in April 2013. A pictorial representation of the SHeS design structure is available to view on the SHeS website.
Target population: The target population is people living in private households in Scotland. The age range has extended over the survey series: 16-64 years in 1995, 2-74 years in 1998, individuals of all ages from 2003.
Sample size: In 2014, the achieved national sample sizes for the core module were 4,659 adults and 1,668 children. For individual health boards, minimum sample size has been reduced from 784 to 500 adults over the four-year period (2012-15). As in 2008-11, health boards continue to have the option to boost their target sample (for the 2013 survey, Ayrshire and Arran, Fife, Grampian and Western Isles opted to boost the main sample in their areas).
Response rate: The 1995 and 1998 surveys sampled one adult per household but in 2003 the design was altered to include all adults per household. Thus in 1995 and 1998 there was no distinction between household and individual response rates - 81% in 1995 and 76% in 1998. In 2003, household response declined to 68% and individual response to 60%. Between 2008 and 2013, household response ranged from 61-66% and individual response from 54-56%.
Method of data collection: Most of the questions are asked by an interviewer using Computer-Assisted Personal Interviewing (CAPI). Questions which are more sensitive in nature are asked via a self-completion booklet.
Smallest geographical unit reported: The one-off surveys were designed to provide data at national and regional levels, with regional results reported for seven 'health regions' based on amalgamations of the 15 health boards which existed at the time. Since 2008, the survey has been designed to provide national results annually and Health Board level data every four years.