Validity of Adolescent Self-Report of Substance Use

Abstract

The validity of self-report of substance use was examined in 367 adolescents referred for a substance use assessment between 1996 and 2000. Referrals came from a wide variety of sources, including pediatricians, the courts, social services, as well as self-referred by their parents. Average age of the sample was 15, 52% were male, and 82% were Caucasian. Adolescents were first asked about the details of their substance use by a clinician using a structured interview with established reliability and validity (Adolescent Drug and Alcohol Diagnosis). They were subsequently asked to provide a urine sample, a requirement they were unaware of when being interviewed about their substance use. If the urine sample was deemed valid by the laboratory technician it was analyzed by means of fluorescence polarization immunoassay and paper chromatography. If positive screens were obtained for any substance, the sample was subjected to gas chromatography/mass spectrometry for confirmation and quantification. Biochemical test results were compared to self-report. Overall, 28% (96/338) of the self-reports were not corroborated by urinalysis. Twenty-six percent (56/219) of adolescents who reported nonuse of a substance had a positive urinalysis. More surprisingly, 34% (40/119) of adolescents reporting substance use in the urinalysis detection window had a negative urinalysis. The present study found self-report of substance use in adolescents to only have fair validity. It is recommended that biochemical corroboration be routinely used for this population.KEY WORDS: urinalysis, adolescent, substance use, self-report, validity Validity of Self-Report 3 RÉSUMÉ La validité de l'auto-évaluation a été étudiée chez 367 adolescents qui se sont soumis à une évaluation au regard de l'utilisation de substance entre 1996 et 2000. Les références émanaient d'une grande variété de spécialistes, notamment les pédiatres, des décisions judiciaires, des données obtenues auprès de services sociaux et d'individus se présentant spontanément sous les conseils de leurs parents. L'âge moyen des participants était de 15 ans; parmi les participants, 52% étaient des hommes et 82% d'origine européenne. Un clinicien a d'abord interrogé les adolescents sur leurs habitudes d'utilisation de substance à l'aide d'un questionnaire détaillé reconnu (Adolescent Drug and Alcohol Diagnosis). On les a ensuite invités à fournir un échantillon d'urine, ce à quoi les adolescents n'avaient pas été informé au départ. Lorsque l'analyse, faite par un technicien de laboratoire, donnait un résultat positif, l'urine faisait ensuite l'objet d'examens plus poussés : polarisation de fluorescence, immunoessai et chromatographie sur papier. Si des résultats positifs étaient obtenus à l'égard de n'importe quelle substance, l'échantillon était alors soumis à la chromatographie en phase gazeuse et à la spectrométrie de masse afin de confirmer les résultats initiaux, de même qu'à une évaluation quantitative. Les résultats des tests biochimiques étaient ensuite comparés aux informa...

A comparison of privileged access interviewing and traditional interviewing methods when studying drug users in treatment

“…It is conceivable that the reason is a shorter social distance between the interviewer and the respondent, a hypothesis propounded by previous research (Kuebler and Hausser 1997, Johnson et al 2000, Williams and Nowatzki 2005. Another possibility is that the respondents did not try to hide certain sensitive behaviors from the PAIs since they, by virtue of their acquaintanceship, already knew that the PAIs had prior knowledge of them.…”

“…Overreporting may be due to individuals exaggerating their drug use in connection with assessments, in order to increase their chances of receiving help (Darke 1998, Williams andNowatzki 2005). Apparent over-reporting may also increase when self-reported drug use cannot be confirmed through urine-or blood-based drug tests.…”

“…Furthermore, there are no apparent differences in validity between PWID and patients in treatment (Darke 1998). However, there are signs that under-reporting may be common among less experienced drug users, in particular among adolescents (Williams andNowatzki 2005, Magura 2010). …”

“…They may also tailor their responses to correspond to what they think the interviewer expects to hear (Webb 1981). Such effects may be intensified if the questions asked are of a sensitive nature, or seen as threatening (Power 1994), or if the social distance between interviewer and respondent is great (Johnson et al 2000, Williams andNowatzki 2005).…”

“…Criterion validity is often high when it comes to common drugs such as tobacco, alcohol, and cannabis, while under-reporting is more frequent for harder drugs where the social acceptance is lower (Darke 1998, Thornberry and Krohn 2000, Williams and Nowatzki 2005.…”