An ancient, traditional remedy for insomnia—the scent of lavender flowers—has now been proved effective. In a recent study, 30 volunteers with chronic insomnia slept each night for three weeks on lavender-scented pillows in a controlled room where the

The author suggests that lavender could work as a remedy for insomnia of which efficaciousness shows within a short period of time. The author cites a recent study to prove the argument. However, the author fails to provide sufficient evidences to support the claim.

First, the author does provide information regarding the representativeness of those 30 volunteers participated in a recent study. There is no data of demographics of those subjects and if the study participants were selected through random assignment according to their demographic data. The author needs to show more information regarding how those volunteers were gathered, which could either strengthen or weaken the argument.

Second evidence that needs to be provided is the details of electrical monitoring the study employed. How intensively the electronical monitoring is done about the participants sleep has to be present. To elaborate that, the accuracy, the frequency of measuring, and the method have to be cited for effective evaluation of the study method. If further evidence of the study method fails to show efficacy of the device, the author's claim will become gratuitous.

Third, the author has to give further information regarding the study subjects' responses. Even if the electronical device proves to be efficacious, the participants' sleep quality and tiredness are also dependent on their responses. Thus, evaluation of the objectiveness of those responses is required since their answers could be out of placebo effect. Without the evidence of how objective those responses are, reliability of those answers will remain questionable.

Lastly, the evidence that it is solely lavender that had an effect on insomnia is needed. There is a possibility that participants' insomnia was improved owing to other confounding variables, not lavender. It could be differences in room temperature, weather, presence of bugs, and lighting that affected largely on those volunteers' sleep quality. The author is required to provide evidences manifesting that lavender was the single variable that had an impact on the change in the participants' sleep quality.

In sum, aforementioned evidences should be provided for the author to strengthen the claim that lavender cures insomnia within a short period of time. Accurate evaluation will be available only after considering detailed evidences.