On causal inferences from retrospective and observational studies and their implications for neuraxial labor analgesia: the CHRISTMAS* study.

Background: Observational studies should not be used to infer causation as they are prone to confounding factors, selection bias, and reverse causality. Many observational studies of labor analgesia treated epidurals as an independent exposure and concluded that "epidurals" cause dystocia, despite multiple randomized controlled trials showing no effect. We highlight this problem using reductio ad absurdum.

Ambient temperature exposure and rapid infant weight gain.

Background: Childhood obesity is a major public health concern, and the global rate is rising. Rapid infant weight gain is a risk factor for later overweight. Studies have linked prenatal ambient temperature exposure to fetal growth, and preliminary evidence suggests postnatal exposure may be associated with infant weight gain.

Adherence to diabetes quality indicators in primary care and all-cause mortality: A nationwide population-based historical cohort study.

Background: In the last three decades, much effort has been invested in measuring and improving the quality of diabetes care. We assessed the association between adherence to diabetes quality indicators and all-cause mortality in the primary care setting.

Methods: A nationwide, population-based, historical cohort study of all people aged 45-80 with pharmacologically-treated diabetes in 2005 (n = 222,235).

Maternal hybrid immunity and risk of infant COVID-19 hospitalizations: national case-control study in Israel.

Hybrid immunity, acquired through vaccination followed or preceded by a COVID-19 infection, elicits robust antibody augmentation. We hypothesize that maternal hybrid immunity will provide greater infant protection than other forms of COVID-19 immunity in the first 6 months of life. We conducted a case-control study in Israel, enrolling 661 infants up to 6 months of age, hospitalized with COVID-19 (cases) and 59,460 age-matched non-hospitalized infants (controls) between August 24, 2021, and March 15, 2022.