ESENER-PSR 2009 - European Agency for Safety and Health at Work

decided to take part in the interview. The personnel manager of the chosen establishment
might not be willing to participate or might not be available during the fieldwork period. 20
By applying the described procedure it is ensured that all establishments with 10 or more
employees - including the headquarters where usually the respondent of the first contact is
located - have a chance 21 to be chosen for the interview.
4.2.2 Alternative approach: Yellow Pages-based sampling
Theoretically, an alternative approach for getting establishment addresses in a country with
no suitable establishment register would be to randomly draw a number of addresses from the
Yellow Pages and set up quotas for the various size-classes and sectors of activity. The
chosen addresses then have to be contacted and screened for both size-class and sector of
activity. Finally, an interview can be conducted in all those workplaces which turn out to have
ten or more employees. In the course of the fieldwork, cell by cell then has to be closed as
soon as the quota set for the cell (sector of activity/size-class) are complete. In the “closed”
cells, no further interview can be conducted.
This alternative solution seems quite plausible at a first glance, but it has a series of major
disadvantages:
As the chosen addresses do not provide any information about the number of employees, an
enormous number of futile contacts with establishments below the set size-threshold of 10
employees is unavoidable. The absolute number of large-sized establishments is very low in
most countries, but due to the disproportionate sampling-approach a large number of
interviews have to be conducted in larger establishments. Using an address-register without
any information about the size of an enterprise, it is therefore hardly possible to meet the
quota of the largest size-classes, whereas the cells with the smaller enterprises fill up pretty
soon 22 . The dimensions of this problem can not be over-emphasized, as the figures from
Germany show in an exemplary way:
20
Yet the rate of non-response can be expected to be lower than with a completely “fresh” address,
because the interviewer can refer to the previous contact with another part of the company – usually
the headquarters.
21
It has however to be noted that this procedure does not produce a “perfect” sample, since the
statistical chance of being selected for the interview is not equal for all units: Units of multi-site
enterprises have a smaller chance of being selected since of each multi-site enterprise only one of
the establishments is selected for the interview. In an establishment address register, in turn,
establishments of multi-sites have the same statistical chance of being selected than single-site
companies.
22 Similarly, it would be difficult to meet the quota for the industry-sectors, as these are often only
partially listed in Yellow Pages due to their limited interest in being contacted by the public.
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