Good practices for the design, analysis, and interpretation of observational studies on birth spacing and perinatal health outcomes

• DOI: 10.1111/ppe.12512
• Publication Date: 2018-10-12T13:24:04Z
• Authors: Jennifer A. Hutcheon; Susan Moskosky; Cande V. Ananth; Olga Basso; Peter A. Briss; Cynthia D. Ferré; Brittni N. Freder...; Sam Harper; Sonia Hernández‐Díaz; Ashley H. Hirai; Russell S. Kirby; Mark A. Klebanoff; Laura Lindberg; Sunni L. Mumford; Heidi D. Nelson; Robert W. Platt; Lauren M. Rossen; Alison M. Stuebe; Marie E. Thoma; Catherine J. Vlad...; Katherine A. Ahrens
• Keywords: Perinatal mortality

Meta-analyses of observational studies have shown that women with a shorter interpregnancy interval (the time from delivery to start subsequent pregnancy) are more likely experience adverse pregnancy outcomes, such as preterm or small for gestational age birth, than who space their births further apart. However, the used inform these estimates methodological shortcomings.In this commentary, we summarise discussions an expert workgroup describing good practices design, analysis, and interpretation perinatal health outcomes.We argue inferences drawn research in field will be improved by careful attention elements as: (a) refining question clarify whether goal is estimate causal effect vs describe patterns association; (b) using directed acyclic graphs represent potential networks guide analytic plan seeking effects; (c) assessing how miscarriages terminations may influenced classifications; (d) specifying key factors previous loss, intention, maternal socio-economic position considered; (e) examining if association between outcome differs age.This commentary outlines recent workgroup, describes several suggested principles study design analysis could mitigate many sources bias.