I dont feel like wasting space and putting full-text articles up, I'm going to quote them and give credit&references, if anyone wants the full texts to examine the methodology or anything else just PM me...
Quote:
PURPOSE We undertook a study to estimate the sufficiently important difference (SID) for the common cold. The SID is the smallest benefit that an intervention would require to justify costs and risks.
METHODS Benefit-harm tradeoff interviews (in-person and telephone) assessed SID in terms of overall severity reduction using evidence-based simple-language scenarios for 4 common cold treatments: vitamin C, the herbal medicine echinacea, zinc lozenges, and the unlicensed antiviral pleconaril.
RESULTS Response patterns to the 4 scenarios in the telephone and in-person samples were not statistically distinguishable and were merged for most analyses. The scenario based on vitamin C led to a mean SID of 25% (95% confidence interval [CI] 0.23–0.27). For the echinacea-based scenario, mean SID was 32% (95% CI, 0.30–0.34). For the zinc-based scenario, mean SID was 47% (95% CI, 0.43–0.51). The scenario based on preliminary antiviral trials provided a mean SID of 57% (95% CI, 0.53–0.61). Multivariate analyses suggested that (1) between-scenario differences were substantive and reproducible in the 2 samples, (2) presence or severity of illness did not predict SID, and (3) SID was not influenced by age, sex, tobacco use, ethnicity, income, or education. Despite consistencies supporting the model and methods, response patterns were diverse, with wide spreads of individual SID values within and among treatment scenarios.
CONCLUSIONS Depending on treatment specifics, people want an on-average 25% to 57% reduction in overall illness severity to justify costs and risks of popular cold treatments. Randomized trial evidence does not support benefits this large. This model and these methods should be further developed for use in other disease entities.
I have a problem with how this study was conducted, I dont think it gives any concrete proof that any of the above listed substances are therapeautic. The study was based off of people who answered "Yes" to whether or not they had a cold. No cultures were ever taken, half of the people could have had a bacterial infection. Then they were later asked to "recall" symptoms...Im just posting this article as an example of something someone on this board might post as "concrete evidence" that Vitamin C is the wonder drug of the 21st century, when in fact upon closer examination of the actual study and how it was conducted, its far from it. You cant rely on an abstract to tell you if the research was credible, you have to look at the entire thing yourself.
Quote:
To be eligible for either arm of this study, prospective adult participants had to answer "yes" to the question, "Do you think that you have a cold or are coming down with a cold?" They also had to report at least 1 of 4 cold symptoms (sneezing, runny nose, nasal obstruction, or sore throat), and to have a total Jackson score of at least 2 points. Jackson scores13–15 are simple sums of severity ratings (1 = mild, 2 = moderate, 3 = severe) for 8 symptoms: those noted above plus cough, headache, chilliness, and malaise.
Quote:
From May 6, 2003, when the study began until August 22, 2005, when data collection ended, 983 people contacted our research team, and 253 enrolled in 1 of the 2 groups reported here. Of the 730 not enrolled in this study, 217 joined another study, 201 did not meet inclusion criteria, 128 declined to participate, and 43 were simply calling for information. Some 141 could not be categorized meaningfully. Of those excluded, 55 were thought to have allergy or an illness other than a cold, 35 had symptoms for more than 7 days, 25 were younger than 18 years, 19 were considered unreliable after the screening interview, and 67 were excluded for a variety of other reasons. (Our screening protocol allowed people to be excluded for more than one reason.)
Im going to add this last part in, and it should totally discredit this article from even being included in an argument such as this-
Quote:
Next, the participant was presented with 1 of the following scenarios:
A 10-cent vitamin pill must be taken 3 times daily for the first 3 days of your cold. There are no significant risks or side effects to this treatment. It is unlikely that the length of your cold would be reduced significantly. Severity of symptoms might be reduced by as much as 30%.
A 20-cent lozenge must be dissolved in the mouth every 2 to 3 hours while awake for the first 3 days of your cold. Side effects may include bad taste, and, very occasionally, nausea. It is possible that the length of the cold could be reduced slightly. Severity of symptoms might be reduced by as much as 30%.
A 50-cent dropperful of an herbal extract must be taken 3 times each day for the first 3 days of your cold. Side effects are limited to bad taste. It is possible that the length of the cold could be reduced slightly. Severity of symptoms might be reduced by as much as 30%.
A $2 prescription-only pill must be taken 3 times daily for the first 3 days of the cold. Side effects are unknown. Preliminary data suggests an average 24-hour reduction in the length of your cold. Severity of symptoms might be reduced by as much as 30%.
The scenarios were presented in varied order, so that each scenario had an approximately equal chance of being considered first, second, third, or last. After each scenario was presented, participants were asked, "Would you take this treatment?" and then, "Why?" or "Why not?" Brief notes were taken regarding the answers to these qualitative questions. Next, participants who had answered "yes" to the original question were asked: "Would you take this [treatment] if it were able to reduce severity by 20%?" If the answer was still "yes," the hypothetical severity reduction was lowered to "10%," then if still "yes," it was lowered to "5%," and, finally, "any?" If the original answer was "no," severity reduction benefit was increased to "40%," then if still "no," it was increased to "50%," then "75%." Severity reduction SID was defined as the smallest severity reduction that justified the treatment scenario for that participant.
Woops...meant to add this in-
Sufficiently Important Difference for Common Cold: Severity Reduction
Bruce Barrett, MD, PhD1, Brian Harahan, BA1,2, David Brown, PhD3, Zhengjun Zhang, PhD1 and Roger Brown, PhD1
1 Department of Family Medicine, University of Wisconsin, Madison, Wisc
2 School of Medicine, University of Wisconsin, Madison Wisc
3 Provincial Health Services Authority, and Department of Family Practice, University of British Columbia, Vancouver, British Columbia, Canada
CORRESPONDING AUTHOR: Bruce Barrett, MD, PhD, Department of Family Medicine, University of Wisconsin, 777 South Mills, WI 53715, [email protected]