National Statistics Omnibus Survey

Nina Parry-Langdon

Office for National Statistics

11 May 2007

ONS Social and Vital Statistics Division (SVS)

• SVS relocated to ONS HQ in Newport

• The NS Omnibus is one of the social surveys in SVS (e.g. GHL, LFS, FES)

• Experienced in running large scale random sample household surveys

Omnibus Survey

• Background

• Who uses the NS Omnibus

• Why and what is it used for

• Maintaining quality

• Survey design

• How can it be used?

Background

- Running since 1990

- 12 survey months since April 1995

- Random sample survey

- Good response rate

- Fast data delivery

- Maintenance of data quality

Who can use the NS Omnibus?

• Non-profit making organisations

- government departments

- academics

- charities

Why use the NS Omnibus?

The Omnibus Survey is a multipurpose survey that offers a fast, cost-effective and reliable way of obtaining information on a variety of topics too brief to warrant surveys of their own

What is the Omnibus used for?- Measuring public awareness of new policies- Providing quick answers to questions of

immediate policy interest- Measuring the effect of publicity campaigns- Question testing and piloting- Providing a sample of respondents for follow-

up investigations (subject to respondents' consent)

note: personal information is not linked to survey responses

Topics• Public confidence in official statistics• Contraceptive use and sexual health• Smoking and drinking behaviour• Cooking behaviour• Food safety• Fire safety• Gambling• E-society• Pensions

Omnibus services• A focus on customer care including advice on

question design if needed

• Client outputs

- technical report - frequency counts - tables - over 60 classificatory variables - the complete dataset - sampling errors

Additional Omnibus services

• Derived variables

• More complex data analysis

• Interpretative report

• Publication

Maintaining Data quality

Three main areas:

1. Sample/weighting

2. Data collectors

3. Data production

Sample• Random probability sample

• Sampling frame - PAF ‘small users’

• Sampled area - Great Britain

• Sample size - each month 67 postal sectors are selected

- 30 addresses at each sampling point

- 1 adult per household at random at

each address

• Achieved - around 1800 addresses

each survey month

Weighting

From April 2005:

• New weighting system to correct for non-response bias• Gross up data by age/sex/region • Population control totals used on the LFS• Improve precision for most variables• Weights supplied at a person level for each month• Sample errors provided

Data collectors• From general SSD pool

- rigorous recruitment

- 4-day interviewer training programme

• Specific Omnibus training

• Post-briefing exercise

• Support from field based regional managers

• Support from HQ field staff

• Inexperienced interviewers restricted

Data production

• Computer Assisted Personal Interviewing (CAPI)

• Data checking

• Data cleaning

• Recoding

• Table checking

Quality Indicators

• Omnibus monthly response rate

• Individual interviewer’s response rates

• Interviewer experience

• Length of interview

• Number of reissues

• Amount of post fieldwork editing

• Timeliness of outputs

Cost• Different costs for:

– simple pre-coded questions– showcards– multi-codes

• Discounts for:– repeated modules – questions asked of e.g. < 30% of the sample

Example survey month: June • Closing date for final questions 14 May

• End of programming 29 May• Field testing of questionnaire 29 May - 6 June

• Questionnaire scatter 7 June• Survey fieldwork dates 11 June - 7 July• Data ready for Research 17 July - 19 Aug

• Data & reports delivered to clients 20 Aug

Survey Timetable

How can the Omnibus data be used?

Omnibus clients:

• Trend analysis (repeat modules)

• ‘snapshot’ of opinions/awareness

• Merge datasets for in-depth analysis

How can the Omnibus data be used?

Recent Omnibus reports:

• DoH/Information Centre for health and social care:

- Contraception and Sexual Health, 2005/06- Drinking: adults behaviour and knowledge in 2006

- Smoking-related behaviour ad attitudes, 2005

• Department for International Development: - Public attitudes to development 2006

Dissemination Press releases

e.g. Report on Contraception and Sexual Health, 2005/06

Headline findings include

• One fifth (20 per cent) of women aged 16-49 had undergone a test for Chlamydia at some point in the past, of whom 27 percent had done so in the previous year

• Awareness of Chlamydia is increasing. The proportion of people who recognised that it is a sexually transmitted infection (STI) has increased sharply since the question was first asked in the 2000/01 survey from 35 per cent to 79 per cent of men and from 65 per cent to 91 per cent for women.

Omnibus archived data

• One year after the survey month

• Public access via the Data Archive

• Non-disclosive data

• Restricted data

Contacts

• Omnibus telephone query: 01633 655810

• E-mail: Omnibus@ons.gov.uk

• Website: www.statistics.gov.uk