Charts showing different averages across age or sex groups can invite conclusions that the investigators never formally tested. A lisdexamfetamine item-level analysis deliberately used descriptive presentation, making that boundary central to its interpretation.
What data were reanalyzed?
Weisler and colleagues examined two previously reported four-week randomized placebo-controlled trials: one in children aged 6–12 and another in adults aged 18–55. These were secondary analyses of existing trials, not new participants or independent replications.
The analysis grouped participants by age bands and sex and examined individual items on the ADHD Rating Scale IV. Adult ratings used prompts intended to capture adult manifestations of symptoms. The original studies used oral lisdexamfetamine doses of 30, 50 or 70 mg/day.
What did the descriptive patterns suggest?
Baseline symptom-item means were generally numerically similar across age-by-sex subgroups. Inattention item scores tended to exceed hyperactivity/impulsivity scores in older participants. Mean endpoint scores were lower after active treatment across the displayed subgroups.
Those observations describe the plotted data. They do not quantify a statistically established treatment-by-age or treatment-by-sex interaction. A numerical difference alone cannot establish that one subgroup responds more strongly.
Why did the authors avoid a comparative test?
The paper expressly chose descriptive presentation rather than comparative statistical analysis. Subgroup composition, sample limitations and the exploratory purpose influenced that decision. The absence of a formal test also means the analysis did not demonstrate equivalence between subgroups.
A phrase such as “regardless of age or sex” must therefore be understood as a description of broadly similar observed patterns, not proof that demographic characteristics never modify response.
The recruitment criteria matter
The pediatric trial excluded predominantly inattentive ADHD presentations. That selection can influence apparent sex differences because the sample does not include the full distribution of symptom presentations seen clinically.
Adults and children were also drawn from separate trials with different rating contexts. Comparing their averages is not a longitudinal study showing how the same people’s symptoms evolve with age. Endpoint included early termination, rather than exclusively complete four-week follow-up.
What is the defensible use of this evidence?
The report helps identify questions about symptom composition and shows why total scores can conceal item-level patterns. It does not establish a demographic rule for prescribing, a biological explanation for sex differences or a universal amphetamine-response profile.
This historical, exploratory reanalysis should accompany, rather than replace, the original randomized trial results. It also provides no individual measurement of intoxication, functional incapacity or driving performance.
Scientific source
Weisler RH, Adler LA, Kollins SH, et al. Analysis of individual items on the attention-deficit/hyperactivity disorder symptom rating scale in children and adults: the effects of age and sex in pivotal trials of lisdexamfetamine dimesylate. Neuropsychiatric Disease and Treatment. 2014;10. doi:10.2147/NDT.S47087. Original commentary on the supplied paper.
Leave a Reply