The PIAAC longitudinal study in Germany: rationale and design

Large-scale Assessments in Education

An IERI – International Educational Research Institute Journal

Table 1 PIAAC-L design and sample size for each of the three follow-up waves

Year	Wave	Unit	Focus	N		RR (in %)
Year	Wave	Unit	Focus	Gross	Net	RR (in %)
2014	Wave 1	Anchor person	Extensive background information	5225	3758	71.9
		Additional house-hold members	Extensive background information	4214^a	2473
		Household	Household composition, living conditions	5225	3737
2015	Wave 2	Anchor person	Direct assessment of key competences (PIAAC numeracy and literacy; NEPS math and reading), PIAAC background variables and additional information	3758	3263	86.8
		Spouse or partner	Direct assessment of key competences (NEPS math and reading), PIAAC background variables and additional information	2103	1368
2016	Wave 3	Anchor person	Basic cognitive competences (SOEP), extensive background information, alternative question operationalizations	3510^b	2967	84.5
		Additional house-hold members	Basic cognitive competences (SOEP), sociodemographic characteristics, alternative question operationalizations	3165	1915
		Household	Household composition, living conditions	3510	2946

N (Gross), number of persons (e.g. anchor persons) that were fielded; N (Net), number of realized interviews; RR, field response rate (gross/net) for anchor persons
^aThe gross sample for the additional adult household members is based on the number of adults in the households of participating anchor persons as indicated in the household protocol
^bA few specific non-interview dispositions, e.g. persons who were unavailable during field period in Wave 2, were included in the gross for Wave 3