Fragile families: Sample and design

This paper provides important background information on the Fragile Familie s and Child Wellbeing Study, and is the first and only paper to provide det ailed information on the research methodology and sampling strategies emplo yed. The bulk of the paper is devoted to a detailed description of the thre e-stage sampling process that was used to obtain a nationally representativ e sample of non-marital births in large US cities. First, it was necessary to sample cities that, collectively, were nationally representative and had maximum variation in policy regimes. Next, it was necessary to sample hosp itals so as to be representative of non-marital births in each city. Finall y, we sampled births in order to be representative of those at each hospita l. The paper concludes with some general information about the study and a simple description of the baseline non-marital sample from the first seven cities.