Background: Screening for prenatal drug use is recommended. The NIDA-modified Alcohol, Smoking, and Substance Involvement Screening Test (NM-ASSIST) is a screener for drug use that has not yet been validated with pregnant women. This study aims to assess the substance-specific diagnostic validity of the NM-ASSIST (not including tobacco or alcohol) in pregnant women and determine optimal cut-points for substance-specific substance involvement (SI) scores.
Methods: Five hundred (500) pregnant women were recruited from 2 obstetric practices as part of a larger study of substance use screeners. Participants completed the NM-ASSIST, and provided urine and hair samples for testing. Receiver-operating characteristic curves were derived to determine the optimal SI score cut-points for each drug.
Findings: Prevalence estimates of prenatal drug use as determined by hair/urine drug testing were: cannabis (32.0%), cocaine (9.9%), benzodiazepines (1.0%), prescription opioids (4.3%), and street opioids (1.7%). The proportion of participants screening positive based on optimal SI score cut-points were as follows: cannabis (39.1%), cocaine (2.3%), benzodiazepines (0.8%), prescription opioids (2.7%), and street opioids (1.7%). There were no screen positives for amphetamines, but 6 (1.2%) women had a positive amphetamine hair or urine test. Optimal cut-points to identify prenatal drug use were: cannabis, 2 (area under the curve [AUC] 0.87; sensitivity 0.82; specificity 0.85; diagnostic odds ratio [DOR] 26.9); cocaine, 2 (AUC 0.58; sensitivity 0.17; specificity 0.99; DOR 29.0); benzodiazepines, 15 (AUC 0.59; sensitivity 0.20; specificity 0.99; DOR 38.8); prescription opioids, 3 (AUC 0.61; sensitivity 0.25; specificity 0.98; DOR 18.3); and street opioids, 4 (AUC 0.55; sensitivity 0.13; specificity 0.99; DOR 9.3).
Conclusions: The NM-ASSIST reliably distinguished pregnant women who use cannabis from those who do not, but performed poorly for all other substances. More research is needed to identify screeners that reliably detect all prenatal drug use. Although more cost-prohibitive, a combination of self-report and toxicological screening may be preferable for detecting prenatal drug use.