Review of Diagnostic Screening Instruments for Alcohol and Other Drug Use and Other Psychiatric Disorders

Screening instruments in child and adolescent psychiatry: general and methodological considerations

“…(2) Internal consistency demands that items of the screener or its subscales are homogenous, i.e., measure the same construct(s). (3) If the screen is an interview, inter-rater reliability evaluates the rate of agreement between different raters [12,13].…”

“…Three complimentary main aspects of validity are commonly required for screening instruments: (1) of main interest for a clinical-diagnostic application is the criterion validity; it is an indicator of how well a screener's result corresponds to an individual result on a specified criterion [12,13]. Thereby, two aspects of criterion validity are distinguished in relation to the time between the assessment of screener and criterion: (a) the degree to which the screener can identify individuals who currently have any or a specific psychiatric disorder (concurrent validity; requires nearly simultaneous assessment of screener and criterion in the test construction phase, while, later in practice, some time might pass between screening and formal psychiatric assessment), and (b) the extent to which an individual's score on a screener will accurately predict the individual's future result such as a psychiatric disorder (predictive validity; outcome criterion will reveal only in future and is assessed considerably later than screener) [12,13]. (2) When the focus is less on the result of a screen but rather on its score and the measure of interest is less well defined than, for example, a formal diagnosis but relates to a construct that is not directly assessable (such as intelligence or personality characteristics), the construct validity is assessed.…”

“…Generally reliability is more easily established than validity, and reliability is often first or exclusively described for instruments. Thus, many screeners lack validity data, which makes it difficult to know how clinically useful the instrument is [12,13]. An ideal screening instrument for diagnostic purposes would demonstrate excellent concurrent (predictive) validity by (1) ruling in most if not all patients with the target condition (diagnosis) while (2) ruling out a considerable proportion of those without it.…”

“…Additionally, the screener's differential accuracy should not be largely mediated by confounding conditions, e.g., comorbid emotional or behavioral disorders [17], but its items/components should possess good content, and convergent and/or criterion validity (i.e., indeed measure the target condition) [13]. For example, when tested alongside the gold standard of diagnosis in a clinical interview, the final screener result (e.g., determined by a cutoff score) should not only correspond to the interview result but also each single item of the screener should highly correlate with their respective interview counterparts (both are aspects of convergent validity in dimensional assessments or of criterion validity when presence of symptoms is rated) [13].…”

“…For example, when tested alongside the gold standard of diagnosis in a clinical interview, the final screener result (e.g., determined by a cutoff score) should not only correspond to the interview result but also each single item of the screener should highly correlate with their respective interview counterparts (both are aspects of convergent validity in dimensional assessments or of criterion validity when presence of symptoms is rated) [13]. Further, all aspects and not only parts of the target condition should be assessed by the screening tool (content validity).…”