On 2017 Jul 10, Robert Speth commented:

Recently there has been a spate of advertisements for a new cognition enhancing “proven results, improving memory & performance” dietary supplement, Natrol Cognium®. The advertising says that it has been clinically proven to be effective in 9 clinical trials. One of the trials cited on the website of the manufacturer of Natrol Cognium® is from this 2009 article in J. Med Food.<br> Upon reviewing this paper, I find the results to be suspect and not supportive of the claims that the active ingredient in Natrol Cognium® significantly enhances cognitive performance. In the only comparison with the placebo control group shown in this manuscript, the Natrol Cognium® ingredient-treated group actually performed slightly worse than the placebo group in the CTT-2 test: 74.8 (30.6) versus 74.5 (20.1) seconds, respectively, after a 4-week treatment! It is well-established that placebo treated groups show improvements in double-blind studies. This is why it is necessary to show that the experimental treatment group performs significantly better than the placebo group at the endpoint of the study. In this study there was no significant difference in the reported endpoint performance between the Natrol Cognium® ingredient-treated group and the placebo control group.<br> An additional question of the validity of the statistical analyses in this paper is the claim of a statistically significant (p<0.05), 1.7% improvement in CTT-1 time after taking Natrol Cognium® for 4 weeks. Given the large error variances 41 and 36% of the mean values before and after Natrol Cognium® ingredient-treatment, respectively, (the variance of the mean of the individual before and after difference for a paired comparison analysis is not provided in the manuscript), it is difficult to believe that a 1.7% improvement would be statistically significant or clinically meaningful. Therefore, this report does not support the advertising claims that Natrol Cognium® is clinically shown to improve cognitive performance.

On 2017 Jul 10, Robert Speth commented:

Recently there has been a spate of advertisements for a new cognition enhancing “proven results, improving memory & performance” dietary supplement, Natrol Cognium®. The advertising says that it has been clinically proven to be effective in 9 clinical trials. One of the trials cited on the website of the manufacturer of Natrol Cognium® is from this 2009 article in J. Med Food.<br> Upon reviewing this paper, I find the results to be suspect and not supportive of the claims that the active ingredient in Natrol Cognium® significantly enhances cognitive performance. In the only comparison with the placebo control group shown in this manuscript, the Natrol Cognium® ingredient-treated group actually performed slightly worse than the placebo group in the CTT-2 test: 74.8 (30.6) versus 74.5 (20.1) seconds, respectively, after a 4-week treatment! It is well-established that placebo treated groups show improvements in double-blind studies. This is why it is necessary to show that the experimental treatment group performs significantly better than the placebo group at the endpoint of the study. In this study there was no significant difference in the reported endpoint performance between the Natrol Cognium® ingredient-treated group and the placebo control group.<br> An additional question of the validity of the statistical analyses in this paper is the claim of a statistically significant (p<0.05), 1.7% improvement in CTT-1 time after taking Natrol Cognium® for 4 weeks. Given the large error variances 41 and 36% of the mean values before and after Natrol Cognium® ingredient-treatment, respectively, (the variance of the mean of the individual before and after difference for a paired comparison analysis is not provided in the manuscript), it is difficult to believe that a 1.7% improvement would be statistically significant or clinically meaningful. Therefore, this report does not support the advertising claims that Natrol Cognium® is clinically shown to improve cognitive performance.