Neonatal risk factors for cerebral palsy in very preterm babies

Risk factors for chronic lung disease and asthma differ among children born extremely preterm

“…36 Yet that is not what we found. The discrepancy might reflect our narrow gestational age range (23)(24)(25)(26)(27) weeks) and therefore the inability to compare extremely preterm to term deliveries. Another possible explanation is that our time-oriented models begin with prenatal variables.…”

“…For these timeoriented logistic regression models (TORMs), we categorized sets of antecedents/covariates by the time they occur, or are identified. 20,23 We grouped demographic and pregnancy variables into the socioeco- A final TORM was then created for CLD and asthma at 10 years of age using the same variables from the shared time periods (pregnancy through late neonatal epochs) to compare risk factors for each outcome. We used a step down procedure seeking a parsimonious solution without interaction terms.…”

“…We performed a retrospective analysis using multivariable logistic regression models in which risk factors are ordered in a temporal pattern, so that the earliest occurring predictors/covariates of, first, CLD in the NICU and, second, asthma at age 10 years, are entered first and are not displaced by later occurring covariates. For these time‐oriented logistic regression models (TORMs), we categorized sets of antecedents/covariates by the time they occur, or are identified . We grouped demographic and pregnancy variables into the socioeconomic status(SES)/pregnancy epoch, delivery characteristics and exposures into the delivery epoch, all exposures and characteristics in the first week of life into the early neonatal epoch, and exposures and characteristics occurring or reported prior to discharge from the NICU into the late neonatal epoch.…”

Risk Factors for Chronic Lung Disease in the Surfactant Era: A North Carolina Population-based Study of Very Low Birth Weight Infants

“…30 In successive steps, potential risk factors were entered according to their time period of occurrence (ie, prenatal, immediately after birth, first 48 hours, and Ͼ48 hours). For each time period, the variables allowed to compete in the model were those for which bivariate analyses yielded significant associations with CLD (P Յ .05).…”

Perinatal infection, fetal inflammatory response, white matter damage, and cognitive limitations in children born preterm

“…In other words, we should not attribute to postnatal factors what might be a consequence of risk factors occurring before birth. Time-oriented analyses are of crucial importance in epidemiologic analyses of early antecedents (here: antenatal infection) and late outcomes (here: cognitive limitations at school age) [Allred et al, 1997]. We need to make sure that we do not attribute to later variables (e.g., home environment) what is actually due to earlier variables (e.g., maternal education, which in turn might be associated with her socio-economic and ethnic background).…”