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Continuous Household Survey

Methodology

Each year CSU sets the content of the questionnaire in consultation with client departments. The questionnaire consists of both a household interview and an individual interview with each person aged 16 and over. Both the household and individual questionnaires consist of core items that are included each year, modules that recur on a regular cycle and ad hoc modules. Core items include accommodation, tenure, employment status, employment activity, educational qualifications, adult health and family information. Non-core items include prevalence of smoking, level of alcohol consumption, and sports and leisure activities.

Sample

The CHS is based on a systematic random sample of 4,500 addresses drawn each year from the Land and Property Services Agency’s (LPSA) list of domestic addresses. The LPSA addresses are sorted by district council and ward, so the sample is effectively stratified geographically. Data is collected by personal interview using CAPI, and the interviews are spread equally over the 12 months from April to March. 

Sample Design and Response 

The sample of addresses used for CHS is obtained from the Land and Property Services Agency Valuation List.  In 2009/10 a simple random sample of almost one per cent of domestic properties on the list was selected.  The information covered by the survey is collected by personal interview throughout the year, allocated on a monthly basis.  Interviews were sought of all the adult members (those aged 16 and over) of 4,500 addresses in 2009/10.

Table A.1 Response from all households.

Sample 

2009/10 

Addresses Issued 

4,500 

Ineligible 

508  

Effective Sample 

3,992

Response 

Percentage 

Fully Co-operating including Proxy & Partial 

69 

Refusals 

24  

Non-contact 

6 

Base (100%) 

3,992

 

Of the addresses issued 11 per cent were excluded from the sample as ineligible through absence of any household at the address or because the address no longer existed.  The effective sample was 3,992 addresses.  The minimum information accepted from a household was a fully completed household schedule including basic demographic information on all individuals in the household.  A subset of information was accepted by proxy for individuals with whom it was not possible for the interviewer to make contact within the allocation period.  Outright refusals were obtained from 24% of addresses in the effective sample (Table A.1).  A further 6% of the effective sample addresses could not be contacted during the allocation period. 

 Sampling Error 

Estimates quoted in CHS tables are based on data collected from a sample of the population and are therefore subject to sampling error.  To illustrate this point the confidence limits relating to a selection of CHS percentage figures at 95% confidence interval are shown in table A.2.  It is important to note that some trends observed in the data may be attributable to sampling error particularly where the numbers in the cells are small.

  Table A.2 Sampling error associated with CHS estimates.  

 

Percent
%

95% Confidence interval & Standard error (SE) 

  

Lower 

Upper 

SE 

Household Tenure 2009/10: 

  

  

 

  

Owned Outright

36 

34.2

37.8

0.91

Owned with Mortgage

34

32.2 

35.8

0.90

Rented - NIHE

13

11.7 

14.3

0.64

Rented other

16

14.6 

17.6

0.70

Rent free

2

1.5

2.5

0.27

Base = 100% 

2,761 

  

  

  

  

  

  

 

  

 

  

  

  

  

Percentage of all persons aged 16 and over with internet access

64.63 

64.63

67.37

1.372

Base = 100% 

4,601

  

  

  

 

 

  

  

  

Percentage of all persons aged 16 and over smoking cigarettes

  

  

  

 

All 16 and over

24

22.6

25.4

0.71

Base = 100% 

3,579

  

  

  

  

 

 

  

  

Percentage of all persons aged 16 and over with a mobile phone

 

 

  

 

All 16 and over 

89

88.1

89.9

0.46

Base = 100% 

4,601

     
 


   


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