Corroborate an adult ADHD assessment — don't rely on self-report alone

Systematic review of longitudinal studies (Sibley, Mitchell & Becker, Lancet Psychiatry 3(12):1157-1165). Estimated ADHD persistence into adulthood varies systematically with diagnostic method: persistence is markedly higher using parent/informant report than self-report alone, and higher with structured interviews than rating scales. Directly demonstrates that relying on self-report alone underestimates cases, and that collateral corroboration changes detection.

Du Rietz et al. (J Psychiatric Research). In the same sample, self-report indicated 44% ADHD persistence vs 79% by parent-report. Objective neurocognitive/neurophysiological markers distinguished persisters from remitters well when classified by PARENT report but poorly when classified by SELF report, indicating self-report alone misses genuinely impaired persistent cases that collateral report detects.

Sibley et al. (MTA Cooperative Group), J Child Psychol Psychiatry 58(6):655-662. Longitudinal follow-up of 579 children with ADHD-Combined type into young adulthood. Parent reports yielded higher persistence than self-reports; combining parent AND self rating-scale reports optimized the sensitivity/specificity balance for detecting persistent ADHD, and when parent data are unavailable a structured interview format best salvages self-report accuracy.

Longitudinal female sample showing adult ADHD persistence estimates depend heavily on informant source and diagnostic threshold, corroborating that informant reports capture persistence that self-report alone misses.

Cross-sectional validity study (Alexander & Liljequist). Neither self- nor informant-report was superior in isolation; findings support multimodal assessment. Informants endorsed more severe inattentive symptoms, reinforcing that collateral data adds diagnostic information beyond self-report alone.