Using hair sample analysis in self-reported and observed drug use in pregnant women

As part of a larger study, maternal hair samples from 56 drug using women were collected within 24 hours of parturition and assayed using gas chromatography and/or mass spectrometry for cannabis, heroin, methadone, cocaine, amphetamine, methamphetamine and benzodiazepines. Reported and observed drug use was compared: a Cohens Kappa coefficient of 0.732 was obtained indicating substantial agreement between reported and observed use. Interesting practice issues emerged. These included the wish to please health practitioners and to avoid negative judgements or removal from services. Also, concerns that confidentiality would be breached or that children would be removed from their care and dissatisfaction with information provided by healthcare practitioners when prescribing medication was communicated.