Treatment: Oral Methylphenidate (Ritalin)
Indication: Attention deficit hyperactivity disorder (ADHD)
Current Status: Most commonly prescribed psychoactive drug for treatment (Volkow, 2001)
Study 1: Schachter, Howard M.; Pham, Ba'; et al (2001)
How efficacious and safe is short-acting methylphenidate for the treatment of attention deficit disorder in children and adolescents?
This study was conducted to address the need for a meta-analysis of studies done which had focused on short-acting methylphenidate compared with a placebo. The researchers included previous studies which met the following conditions: "a placebo controlled randomized trial that involved short acting MP and participants aged 18 years or less at the start of the trial who had received any primary diagnosis of ADD that was made in a systematic and reproducible way." (Schacter, 2001)
The 62 studies that were selected had some flaws -- they were randomized trials involving 2897 participants who had a primary diagnosis of ADD. Over 88% of participants were male and using two separate indices the trials exhibited low quality.
In addition, the interventions were conducted over a relatively short time period -- no longer than 28 weeks.
The results of the intervention were reported by both teachers and parents but the possibility of publication bias impacts the positive results achieved by these studies. Even though the results were statistically significant, the length of the placebo-controlled effect was not demonstrated past four weeks.
This meta-analysis indicated that most studies had focused on the efficacy of stimulants relative to other treatments. Very few studies focused on the clinical utility of MP compared with placebo. The authors feel this was a very large flaw in the studies because in order to determine whether a drug is effective, there must be a control (placebo).
Study 2: Nora D. Volkow, Gene-Jack Wang, et al (2001)
Therapeutic Doses of...