Classification Detail

The concept of skill level is applied mainly at the top (major group) level of the classification, giving more emphasis to the first of these operational measures, the nature of the work performed, than to the formal and informal education and training requirements. Four broad skill levels are defined. As a result, eight of the ten major groups in ISCO-08 contain occupations only at one of four skill levels. For example, ISCO Major Group 2: Professionals includes only occupations at the highest ISCO skill level, Skill Level 4. All groups below the major group level contain occupations at only one skill level. Within each major group, occupations are arranged into unit groups, minor groups and sub-major groups, primarily on the basis of aspects of skill specialization. In the case of ISCO-08 Major Group 1: Managers, and Major Group 0: Armed Forces Occupations, the concept of skill level is applied primarily at the second hierarchical level.

At the request of the 17th ICLS in 2003 to make improvement in light of eperience gained in using ISCO-88 based classifications, and as a consequence of developments in the world of work. The timing reflected the request of the 34th session of the Statistical Commission of the United Nations that the work to update ISCO-88 not later than the end of 2007 for the results to be taken into account in national preparations for the 2010 round of population censuses.

The conceptual model used to guide the development of ISCO-08 was no tfundamentally changed from that used in ISCO-88. There are, however, significant differences in the treatment of some occupational groups. These differences reflect the need to address concerns about specific difficulties experienced in the use of ISCO-88, as well as the need to reflect occupational change in the 20-year period following its development. In addition, there were some changes in the way the ISCO conceptual model was applied to the design of the classification. Most notably, the nature of the work performed was given more emphasis than formal education and training requirements in determining the skill level of an occupation. The result of these changes was a modest increase in detail at each level of the classification except at the top level. The 10 major groups at the top level of the ISCO-08 are conceptually the same as those defined in ISCO-88. Since some groups of occupations were moved from one major group to another, however, there is a significant break in series for data classified at the major group level. Some of the more significant changes are summarized below. - The sections of the classification dealing with managerial occupations were reorganized so as to overcome problems experienced by users of ISCO-88. - Some additional unit groups and one new minor group were created for selected supervisory occupations, in areas where supervisors commonly perform significantly different tasks from the workers they supervise. - Occupations associated with information and communication technology were updated and expanded, allowing for the identification of professional and associate professional occupations in this field as sub-major groups. - ISCO-88 included parallel groups appearing in different major groups to cater for cases where the education and training requirements for a particular occupational group differed between countries because of differences in responsibilities and degree of supervision. Parallel groups do not appear in ISCO-08 when the tasks performed are essentially the same. - Occupations concerned with the provision of health services were expanded, in order to provide sufficient detail to allow ISCO-08 to be used as the basis for the international reporting of data on the health workforce. These occupations were grouped together, where possible, to provide two sub-major groups and a separate minor group devoted to occupations in health services. - The section of the classification dealing with office clerks was reorganized to reflect the increasing impact of information and communications technology and to provide more meaningful detail for occupations in which large numbers of women are employed. - The aggregate groups for sales and service workers were reorganized, including the provision of new sub-major groups for personal services workers, personal care workers and protective services workers. - More detailed categories and greater clarity are provided for some occupational groups involved in agriculture. - More detailed categories are provided for occupations involved in the provision of information and services to clients, including those related to tourism. - The groups for plant and machine operators were restructured and reorganized in response to concerns that this part of ISCO-88 was excessively detailed and out-of-date in some areas. - The coverage and visibility of occupations that are significant in informal employment were improved, leading to an associated increase in the number of sub-major groups in ISCO-08 Major Group 9: Elementary Occupations, compared to ISCO-88.