2. EXPLORATION OF THE NONRESPONDENTS IN THE EGLHS
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of N-1246 persons out of 2131 nonrespondents from the initial sample (this means that the
NRS gross sample contains (1246/2131)'100-58,5%33 of the wave 1 nonrespondents). From
this gross sample, 282 persons had to be subtracted due to out-of-date addresses, problems of
finding persons, etc. This is reported as a whole under the title of "neutral loss" in the field
report. The final actualised gross sample of nonrespondents consisted of N=964 persons.
In addition to an announcement letter, an incentive of DM 50,- was offered to all
selected nonresponse target persons. Although the majority of them once again did not
participate (69,5% refused again), 201 nonrespondents finally gave complete interviews in
which CATI/CAPI programmes" similar to the ones in wave 2 were used. We can define the
response rate of the NRS study in three ways: taking all the initial nonrespondents of wave 1
as 100%, à response rate of only 9,4% is calculated (201 out of 2131). Taking the pool of the
NRS gross sample, we end up with a response rate of 16,1% (201 out of 1246). Defining the
actualised gross sample as 100%, we calculate a final response rate of 20,9% (201 out of
964). The last version is given in the infas report.
The Nature of the Nonresponse Sample
Summing up the preconditions of the nonresponse study, we can recognise:
independently from the kind of calculation of the response rate, the NRS sample obviously
cannot be assumed to be a representative selection of all nonrespondents. Thus generalisations
of the findings will be limited. The sample is in principle biased as most of the refusals were
again missed out and so it consequently appears to be a filtered extract of special "difficult"
target persons.
In the next step, we will take a look at the sample development for all parts of the
study in more detail. It was shown above that numbers for percentages depend strongly upon
the basis chosen as 100%. For this reason TABLE 1 follows the absolute number of target
persons from the initially drawn sample until the final survey data set and lists the reasons
why people dropped out.
3 rounded to one decimal
» With slight modifications concerning additional questions about jobs, marriages, partners and education before
1989.