Pianificazione di uno studio caso-controllo multicentrico: un esempio

We planned an observational study to address the clinical question: is twinning a risk factor for acute neonatal surgical intestinal disorders (PAIC)? Multicentric casecontrol studies appear the most appropriate study design among observational ones. The target population consists of preterm infants (gestational age <37 weeks). The primary endpoint is PAIC occurrence from birth to hospital discharge: cases are neonates with PAIC, and controls are neonates without PAIC. Data will be collected from hospital records, extracting all cases and randomly selecting 4 controls from the same center for each case. We will use logistic regression to estimate the odds ratio of having PAIC in twins compared to singletons, after carefully evaluating the causal relationships among the involved variables. The main limitation of this study is the low statistical power, despite the multicentric planning of the study.