The Change in Employer Practices Survey 2002 (CEPS02) was carried out in July–
September 2002 by means of telephone interviewing, and obtained information from
2,000 workplaces with five or more employees, in both the public and the market
sectors. Interviews were approximately half an hour in length. Respondents were either the senior personnel or the HR manager on site or the manager with responsibility
for people, who in small workplaces was usually the proprietor or general manager.
The sample frame was Yell Data, and workplaces were sampled (in accordance with
a sampling plan stratified by industry group and size group) so as to be representative
of industry while being selected with probability approximately proportional to number
of employees. The response rate was 55 per cent. The achieved sample has been
weighted to make it representative of British workplaces with at least five employees,
by means of information from the Inter-Departmental Business Register (IDBR). As
a check on data quality, the proportion of employees at workplaces of 25 or more
employees with a recognised union was compared with the corresponding figure from
the Workplace Employee Relations Survey 1998 (Cully et al., 1999: 88): the two figures
were within one percentage point. This appears reasonable because union recognition
was on a plateau in the late 1990s and early 2000s (Gall, 2004).