In Germany, three large-scale surveys–the Level One Study (LEO), the Programme for the International Assessment of Adult Competencies (PIAAC), and the National Educational Panel Study (NEPS)–provide complementary data on adults’ literacy skills that can be harnessed to study adults with low literacy. To ensure that research on low-literate adults using these surveys arrives at valid and robust conclusions, it is imperative to ascertain the comparability of the three surveys’ low-literacy samples. Towards that end, in the present study, we comprehensively assess the comparability of adults with low literacy across these surveys with regard to their sociodemographic and socioeconomic characteristics. We used data from LEO, PIAAC, and NEPS. We identified features of the sample representation and measurement of (low) literacy as potential causes for variations in the low-literacy samples across the surveys. We then compared the low-literacy samples with regard to their sociodemographic and socioeconomic characteristics and performed logistic regressions to compare the relative importance of these characteristics as correlates of low literacy. The key insight our study provides is that–despite different sample representations and measurement approaches–the low-literacy samples in the three surveys are largely comparable in terms of their socioeconomic and sociodemographic characteristics. Although there were small differences between the surveys with regard to the distribution of gender, educational attainment, and the proportion of non-native speakers within the group of low-literate adults, results revealed that both the prevalence of low literacy and its correlates were largely robust across LEO, PIAAC, and NEPS. Across all three surveys, lower educational attainment emerged as the most significant correlate of low literacy, followed by a non-German language background, unemployment and low occupational status. Our study provides evidence that all three surveys can be used for investigating adults with low literacy. The small differences between the low-literacy samples across the three surveys appear to be associated with sample representation and certain assessment features that should be kept in mind when using the surveys for research and policy purposes. Nevertheless, our study showed that we do not compare apples with oranges when dealing with low-literate adults across different large-scale surveys.

中文翻译：

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关于LEO，PIAAC和NEPS的低文化水平成年人的可比性。方法论上的考虑和经验证据

在德国，三项大规模调查-一级研究（LEO），国际成人能力评估计划（PIAAC）和国家教育小组研究（NEPS）-提供了有关成人识字技能的补充数据，这些数据可以被用来研究识字率低的成年人。为了确保使用这些调查对低文化程度成年人进行的研究得出有效且可靠的结论，必须确定这三个调查的低文化程度样本的可比性。为此，在本研究中，我们就这些调查的社会人口学和社会经济特征，全面评估了识字率低的成年人的可比性。我们使用了来自LEO，PIAAC和NEPS的数据。我们确定了样本代表性和（低）素养测量的特征，这是整个调查中低素养样本变化的潜在原因。然后，我们比较了低识字率样本的社会人口统计学和社会经济特征，并进行了逻辑回归，以比较这些特征作为低识字率的相关性的相对重要性。我们的研究提供的主要见解是，尽管样本代表和测量方法不同，但三项调查中的低识字样本在社会经济和社会人口统计学特征上具有可比性。尽管各次调查在性别分布，受教育程度，以及在非识字成人中非母语人士的比例，结果表明，低识字率及其相关性在整个LEO，PIAAC和NEPS中都具有很强的鲁棒性。在所有这三个调查中，低文化程度是低识字率的最显着相关因素，其次是非德语语言背景，失业和低职业地位。我们的研究提供的证据表明，所有三项调查均可用于调查识字率低的成年人。在这三个调查中，低识字率样本之间的细微差异似乎与样本表示和某些评估特征有关，在将调查用于研究和政策目的时应牢记这些特征。不过，