Randomised or not?

Dear editor

We read with interest the two perspective articles about methylphenidate (MPH) in children with attention deficit hyperactivity disorder (ADHD) published in the previous issue of Evidence-Based Mental Health.^{1 2} Both papers quote a study we published in 1997³ and note that there is an issue about whether it was randomised or not. Our paper was published in 1997, and at that time the requirement for randomisation was different than now. The original research design makes it hard for us to decide whether the study should be classified as randomised or not, so we describe here the procedure for assigning participants used in our study in order to enable each reader to classify the study as they may wish. We tested each participant twice over a period of 3 weeks. The selection of the participants for the study was not random, as we recruited the participants by advertisement. As the participants joined the study, we randomly allocated them to two groups: group 1 (3 weeks on placebo followed by 3 weeks on MPH) or group 2 (3 weeks on MPH followed by 3 weeks on placebo). The participants did not take the medications during the weekend (which is a common procedure with MPH).

We are not going to take a side as to whether our study can be classified as random or not. However, as clinical psychologists with more than 30 years of experience, we would like to state our own impression about the efficacy of MPH with the children, adolescents and adults we treated. In most cases (most of all if severely ill) we saw an improvement in their behaviour, in their emotional condition and to less extent in their cognitive functioning. Most of the parents report bettered performance at school; however, the most common side effects were reduced appetite, more reserved emotional expression and less participation in social activities (mainly during school breaks). We acknowledge that the above brief summary based on our clinical experience is not evidence-based research. Nevertheless, we feel that observation, intuition and the reports of our patients (what we call ‘feelings-based evaluation’) should be used along with scientific evidence when one considers the use of MPH in ADHD.