1. Methodology background

 Survey name  Labour Disputes Survey
 Frequency  Monthly and Annual
 How compiled  Based on third party data
 Geographic coverage  UK
 Last revised  25 October 2017

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2. Executive summary

The Labour Disputes Inquiry collects data on the number of stoppages, working days lost and the number of workers involved in strike action from UK businesses that have been involved in strike action. However, lack of press coverage might mean that some small disputes may be overlooked.

The inquiry tries to record all strike action that has taken place except for those disputes involving fewer than 10 workers or lasting less than half a day. However, we do collect data if 100 working days are lost due to a single dispute, regardless of the number of workers involved. Disputes are picked up from reports in the mainstream media and websites such as The Morning Star and the Socialist Worker, as well as news feed websites like NewsNow. News and union websites are also a primary source of information. Where possible, the data are collected directly from the employer involved in the dispute.

This report contains the following sections:

  • Output quality

  • About the output

  • How the output is created

  • Validation and quality assurance

  • Concepts and definitions

  • Other information, relating to quality trade-offs and user needs

  • Sources for further information or advice

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3. Output quality

This report provides a range of information that describes the quality of the output and details any points that should be noted when using the output.

We have developed Guidelines for measuring statistical quality; these are based upon the five European Statistical System (ESS) Quality Dimensions. This report addresses the quality dimensions and important quality characteristics, which are:

  • relevance

  • timeliness and punctuality

  • coherence and comparability

  • accuracy

  • output quality trade-offs

More information is provided about these quality dimensions in the following sections.

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4. About the output


(The degree to which the statistical outputs meet users’ needs.)

Data from the Labour Disputes Inquiry are used by a wide range of internal and external customers. The figures are used by the Department for Business, Energy and Industrial Strategy (BEIS) to provide ministers with a monthly brief on labour disputes. Other users in government include: HM Treasury, Welsh Assembly Government, the Department for Education and the Advisory, Conciliation and Arbitration Service (ACAS).

Outside government, the data attract interest from the media, researchers, local authorities, development corporations, academics and other users within private industry. In accordance with the Resolution concerning statistics of strikes, lockouts and other action due to labour disputes: 1993, the UK provides the International Labour Organisation (ILO) with data covering working days lost, number of workers involved and the number of stoppages by industry for each calendar year. This information is then published on the ILO statistical website.

Timeliness and punctuality

(Timeliness refers to the lapse of time between publication and the period to which the estimates refer. Punctuality refers to the gap between planned and actual publication dates.)

The inquiry releases data on a monthly and annual basis. The data are published in the timeliest manner possible and it would not be possible to publish any sooner because of the time needed for companies to compile the information. The time lag between the publication and the reference period to which the data refer is as follows:

  • monthly results release: 6 weeks after the reference period

  • annual results release: March, 12 weeks after the reference period

  • annual in-depth analysis: June, 6 months after the reference period

For more details on related releases, the release calendar on our website provides 12 months advance notice of release dates. If there are any changes to the pre-announced release schedule, public attention will be drawn to the change and the reasons for the change will be explained fully at the same time, as set out in the Code of Practice for Official Statistics.

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5. How the output is created

The inquiry tries to record all strike action that has taken place within the UK, except for those involving fewer than 10 workers or lasting less than a day. However, we collect data if 100 working days are lost due to a single dispute, regardless of the number of workers involved. It should be noted that in measuring “stoppages” the statistics exclude disputes that do not result in a stoppage of work. These include:

  • work-to-rule – where a union organises action short of a strike; a work-to-rule means that workers are asked to only work standard hours and not to do anything that is not written in their contracts, this rules out the possibility of overtime and working through core lunch hours

  • go-slows – where workers stage industrial action by slowing down production; this could then have a knock-on effect on the business’s productivity

Disputes are picked up from reports in news and trade union websites. Where possible, the data are collected directly from the employer involved in the dispute. The inquiry uses various ways of collecting data; however, the majority of the data are collected via email questionnaires. Data are also collected via telephone and in the case of some nationwide strikes, a printed questionnaire is sent out.

As the information is usually given by the organisation involved in the action the data are usually considered to be accurate. Press reports and previous returns, where applicable, are checked for validation purposes. For large UK-wide strikes such as local council workers, the numbers of workers and working days lost can be imputed by calculating regional averages of returned data and applying these averages to the business’s total employment. For smaller strikes, the number of workers involved is taken from newspaper reports and used to calculate working days lost.

The inquiry is voluntary and is run as a census and therefore the number of questionnaires dispatched in a monthly cycle is totally dependent on how many cases of industrial action there are in that month. To give an example, in the last 10 years the lowest number of questionnaires dispatched would have been six and the highest would have been in the hundreds. However, the latter would have been for nationwide action, although this would be counted as one strike. The response rates for the inquiry, like the numbers surveyed, vary month-on-month. The average response rate for 2015 was 84%.

Information on who accesses the data on a monthly or annual basis is not available. However, we are aware that estimates are used widely across government. The outputs also attract regular interest from media outlets and the monthly estimates can regularly be found in the press. Among other regular users are: researchers, local authorities, development corporations, academics and private industry.

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6. Validation and quality assurance


(The degree of closeness between an estimate and the true value.)

The Labour Disputes Inquiry, on a voluntary basis, requests the minimum amount of detail to produce the analyses required by users. The overwhelming majority of businesses rarely experience a labour disputes stoppage and consequently do not have formal mechanisms for recording the data. Information is not available on the completeness of coverage, so consequently it is not known what proportion of all stoppages is included in the statistics.

Data are not collected for those disputes involving fewer than 10 workers or lasting less than a day. However, we collect data if 100 working days are lost due to a single dispute, regardless of the amount of workers involved.

Based on the comments received in the last Labour Disputes Triennial Review, the users of the data confirmed that the labour disputes information meets their needs. Users were happy with the level of data produced on a monthly basis so long as a more detailed breakdown was given annually. The public and private split, introduced on the back of a recommendation from the review, has also helped users gain a greater understanding of the data.

The labour disputes monthly provisional results are published 6 weeks after the reference period and the previous period’s data are revised if necessary. Revisions are gener.ally very small as it is unlikely that we miss any major strike activity throughout the year, as large strikes are generally well publicised. All revisions are conducted in line with the National Statistics protocol on revisions.

Comparability and coherence

(Coherence is the degree to which data that are derived from different sources or methods, but refer to the same topic, are similar. Comparability is the degree to which data can be compared over time and domain, for example, geographic level.)

The Labour Disputes Inquiry covers all UK industry using the Standard Industrial Classification (SIC). Data for 1995 to 2002 have been classified according to SIC 1992, data from 2003 to 2008 have been classified according to SIC 2003, and from 2009 data have been classified according to SIC 2007. The broad industrial classifications used by the Labour Disputes Inquiry, however, have meant that this change in classification had minimal impact on the outputs.

We hold UK data on labour disputes going back as far as 1891. Analysis can be provided on various combinations, for example, by industry groups, by standard statistical region from 1958 to 1995, by region from 1996 and by cause (from 1959). We also publish estimates on a public and private split, with data dating back to 1996.

The Resolution concerning statistics of strikes, lockouts and other action due to labour disputes: 1993 has provided the framework for the methodology used by the UK. The UK does not satisfy the resolution in all respects, largely because of the practical difficulties in collecting some of the detail (for example, the basis on which the dispute was settled). Nevertheless, the main recommendations of the resolution are followed.

Our Triennial Mini Review of the Labour Disputes Inquiry, conducted in 2009, recommended this methodology be continued.

There is no other official source of labour disputes statistics in the UK. The UK methodology was compared with 15 other countries for the 2005 version of the Triennial Mini Review. The survey of other countries’ practices shows that the UK’s procedures are typical. Most other countries’ surveys are voluntary and most are conducted in a similar way to the UK.

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7. Concepts and definitions

(Concepts and definitions describe the legislation governing the output and a description of the classifications used in the output.)


The statistics cover stoppages of work in progress in the UK during a calendar year caused by labour disputes between employers and workers, or between workers and other workers, connected with terms and conditions of employment. These include “lock-outs” by employers, where organisations close their sites and will not allow workers to participate in their normal working day and “unlawful” or “unofficial” strikes. The statistics exclude disputes that do not result in a stoppage of work, for example, work-to-rules and go-slows.

Working days lost

Working days lost is defined as the number of days not worked by people involved in a dispute at their place of work. In measuring the number of working days lost, account is taken only of the time lost in the “basic working week”. Overtime work is excluded, as is weekend working where it is not regular practice.

Workers involved

The figures for workers involved are for workers directly involved in strike action at the establishment where the dispute occurred. Workers involved in more than one stoppage during the year are counted in the statistics for each stoppage in which they take part. Part-time workers are counted as whole units.

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8. Other information

Output quality trade-offs

(Trade-offs are the extent to which different dimensions of quality are balanced against each other.)

Data published on a monthly basis are provisional and are open to revisions the following month. The inquiry publishes data as timely as possible, but more reliable estimates may be available the next month when further information may become available.

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9. Sources for further information or advice

Accessibility and clarity

(Accessibility is the ease with which users are able to access the data, also reflecting the format in which the data are available and the availability of supporting information. Clarity refers to the quality and sufficiency of the release details, illustrations and accompanying advice.)

Our recommended format for accessible content is a combination of HTML webpages for narrative, charts and graphs, with data being provided in usable formats such as CSV and Excel. Our website also offers users the option to download the narrative in PDF format. In some instances other software may be used, or may be available on request. For further information please refer to the contact details at the beginning of this report.

For information regarding conditions of access to data, please refer to the following links:

Access to microdata via the Virtual Microdata Laboratory.

Useful links

Eurostat Website on Labour Disputes

International Labour Organisation (ILO)

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