Similar symptom scores among observed patients do not establish that two treatment regimens are equally acceptable. Adverse effects and discontinuation are outcomes in their own right, and they affect which patients remain available for later assessments.
The inpatient comparison
Wang and colleagues’ 2016 report randomized 42 patients with methamphetamine-associated psychosis, 21 per arm, to aripiprazole or risperidone during a 25-day inpatient study. The planned oral protocols allowed aripiprazole 5–15 mg/day and risperidone up to 6 mg/day. The archived manuscript also contains a discordant 9-mg risperidone statement; the protocol range should not be treated as verified individual dosing.
Psychosis scores improved in both groups without significant between-group differences. Retention was lower with aripiprazole (p=0.007). Reported akathisia occurred in 13/21 versus 6/21 patients (p=0.03), and agitation in 11/21 versus 4/21 (p=0.02). Enrollment stopped at 42 rather than the planned 120 because of adverse effects and dropout.
Two distinct questions about treatment performance
The study lacked placebo, was not fully blinded and allowed ancillary medication. The authors acknowledged that symptom improvement could not be separated reliably from self-abatement during abstinence.
The symptom question asks how measured illness severity changed. The retention question asks whether patients continued the assigned regimen. A treatment description should report both. Omitting discontinuation can make the experience of those who tolerated treatment appear to represent everyone initially assigned.
A nonsignificant difference in symptom scores is also not a formal demonstration of equivalence. Establishing equivalence requires an appropriate margin and sufficiently precise evidence. A small comparison terminated early cannot acquire that conclusion simply because its symptom p value exceeded a conventional threshold.
Why the dosing discrepancy matters
The inconsistent passage is a reason to limit dose-specific inference, rather than silently choose whichever number fits a preferred interpretation. Without clarifying information, the article cannot supply a reliable individual dose–response analysis from that text.
The same discipline applies to the adverse-event findings. The counts describe this selected inpatient sample and its accompanying treatment practices. They should not be transformed into universal event probabilities for all people receiving either medicine.
This historical study identifies a meaningful tolerability and retention difference while leaving important efficacy questions unresolved. It does not establish the cause of psychosis in an individual, demonstrate that every symptom resulted from methamphetamine, or provide a current treatment-selection rule.
Source
Wang G, et al. Aripiprazole and risperidone for treatment of methamphetamine-associated psychosis in Chinese patients. J Subst Abuse Treat. 2016;62:84–88. doi:10.1016/j.jsat.2015.11.009. Full-text author manuscript.