NS-SEC classes and collapses
Eight, five and three-class versions
The number of classes used depends both upon the analytic purposes at hand and the quality of available data. Within the conceptual model, it is possible to have eight, five and three class versions of NS-SEC. The nested relationship between the 8, 5 and 3-class versions is given below.
| 8 classes | 5 classes | *3 classes |
| 1. Higher managerial and professional occupations |
1. Managerial and professional occupations
|
1. Managerial and professional occupations
|
| 1.1 Large employers and higher managerial occupations | ||
| 1.2 Higher professional occupation | ||
| 2. Lower managerial and professional occupations | ||
| 3. Intermediate occupations | 2. Intermediate occupations |
2. Intermediate occupations
|
| 4. Small employers and own account workers | 3. Small employers and own account workers | |
| 5. Lower supervisory and technical occupations | 4. Lower supervisory and technical occupations |
3. Routine and manual occupations
Never worked and long-term unemployed |
| 6. Semi-routine occupations |
5. Semi-routine and routine occupations Never worked and long-term unemployed |
|
| 7. Routine occupations | ||
| 8. Never worked and long-term unemployed |
* 3-classes names revised 5 October 2001
+ Presentation of 'Never worked and long-term unemployed' altered on the table above in the five and three class versions. This corresponds more closely to the cautionary notes below. Revised 14 January 2004.
Some cautionary notes about the five and three class versions
The three class version may be assumed to involve some kind of hierarchy. However, none of the other versions can be regarded as ordinal scales, not least because of the recognition of self-employment as a separate class. It is not recommended that users create an ordinal scale by combining the self-employed in Class 4 with the intermediate Class 3. This is because the self-employed are distinctive in their life chances and behaviour. It is strongly recommended that users accept the theoretical and measurement principles of the new classification, take advantage of the conceptual base of the model for developing hypotheses linking it to outcomes of interest, and use appropriate analytic techniques for nominal data.
Users should consider carefully whether to allocate the 'never worked' and 'long-term unemployed' to semi-routine/routine and manual occupations respectively or keep them separate. For example, users performing health analyses would need to be very careful about how the 'long-term unemployed' and the 'never worked' were defined since including the permanently sick would clearly not be sensible. They should be classified on the basis of last main job and the 'long-term unemployed' should include only those who are seeking or available for work. Of course, this may still leave some people who are permanently sick or disabled in the never worked category, hence this warning.
