Methodological Issues in Controlled Studies on Effects of Prenatal Exposure to Drug Abuse: Research Monograph 114

Conceptual issues in behavioral teratology and their application in determining long‐term sequelae of prenatal marihuana exposure

“…Even when data are gathered that provide information both about non‐drug variables during pregnancy and the postnatal environment, the interpretation of the role that these variables play in influencing the teratogenic outcomes is complex and rarely definitive. Much has been written about both the need and the strategies for assessing and controlling a wide gamut of potentially pre‐ and postnatal confounding variables in prospective longitudinal assessments of drug‐exposed offspring (e.g., Bellinger, 2000; Fried, 1998; Jacobson & Jacobson, 1996; Kilby & Ashgar, 1991; Wetherington et al., 1996). However, even with this emphasis, it is important to keep in mind that the frame of reference for behavioral teratology is not that the focus teratogen is the best predictor of the dependent variable being assessed, but rather that the drug of primary interest continues to have predictive power after appropriate statistical control for other significant predictors (Streissguth, Barr, Sampson, Darby, & Martin, 1989).…”

“…Logistically, the commitment that is needed from investigators, participating families and funding agencies to undertake a study that will follow a sample for more than a year or two is a major hurdle. Even more daunting, however, are interpretative issues which arise when the investigator must juggle combining both the disciplines of developmental psychology and neurotoxicity while factoring in the complexity of events that occur during the passage of time between the prenatal exposure and the later postnatal behavioral measures (Fried, 1998; Kilbey & Asghar, 1991; Wetherington, Smeriglio, & Finnegan, 1996). These ubiquitous methodological factors have contributed to a degree of resistance and uncertainty in the acceptance of longitudinal teratologic findings which parallel those noted 25 years ago but which have a somewhat different basis.…”