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1. I found an ad on the internet for a product called “Blood Pressure High." This was the former location of the ad:
   http://www.naturallydirect.net/lowering-blood-pressure.htm.
   The ad contains a lot of information, explaining the origin of blood pressure and the different things a person can do to maintain a healthy blood pressure, including taking an herbal supplement such as this one.
2. I do not have experience with this product, but I am somewhat skeptical of the claim because this site claims to have remedies for everything from aging to menopause to expelling worms from the digestive tract.
3. The ad claims: “Blood Pressure High is a herbal formula that improves circulation, helping to control or reduce blood pressure levels.” I can restate this claim as a testable hypothesis as follows: Taking Blood Pressure High decreases blood pressure.
4. The ad recommends a daily dose of two capsules, each containing a mix of four herbs (hawthorn, yarrow, cayenne, and garlic). They do not say how long it will take to see results, so I will assume that a treatment time of 60 days (2 bottles worth) will be sufficient to see measurable results. My overall experiment strategy will be to recruit volunteers with high blood pressure to take either the herbal product or a placebo.

• the experimental subjects will be adults suffering from high blood pressure but otherwise in good health (e.g. no other known chronic illness).
• there will be two treatment groups, with a sample size of 1000 subjects each (2000 experimental subjects all together). Half the subjects will take the herbal product for 60 days in the recommended dose; the other half will take 2 capsules of a placebo for the same duration.
• each subject will be assigned at random to a treatment group.
• the control group will receive a placebo of two sham capsules per day. The capsules themselves will be made of the same material as the herbal formula capsules (e.g. gelatin). Instead of the herbal mix in the herbal formula, the placebo capsules will contain an inert substance that we already know does not affect blood pressure in the long term (perhaps corn starch or sugar). I chose this control because it is the same as the herbal treatment except that it replaces the active ingredient with an inert ingredient.
• (1) since diet affects blood pressure, all subjects, regardless of treatment, should follow the same dietary guidelines. (2) Since stress contributes to blood pressure, perhaps the subjects should also have the same general sorts of occupations. (3) Smoking also contributes to blood pressure, so all subjects should be nonsmokers.
• I will measure blood pressure before and after the 60 day period during which the subjects take the herbal formula or the placebo.
• If the product really is effective, I predict that after 60 days, the average blood pressure in the subjects receiving the herbal treatment should be lower than at the start of the experiment. The average blood pressure in the control subjects should remain unchanged.

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[Sample by Mariëlle Hoefnagels. Please note that the product's name and specific claims have now changed. That's why the ad does not exactly match what this sample says.]

Contemporary Issues in Biology -- BIOL 1003 Mariëlle H. Hoefnagels, Ph.D. © 2004-2015. biology1003 at OU dot edu (at = @, dot =.) Last Updated August 5, 2014 11:02 PM