“項目有11k 受驗者, 29次研究“ 其實份paper嘅意思係 29份研究總共有11k participants,夾埋左d stat。兩者好大分別: - 雖然 review 嘅可信度較 RCT 高 但是不能忽略 participants 本身嘅條件未必一樣。份paper 自己都話results有 heterogenity, included 同 excluded 嘅studies 有時會好大影響,因為d comparing variables/ research sample size/ and many more factors 每一分都唔同 正如豆奶對不同種族的人有不同影響。Vit C 對不同年齡、種族的人可能也有不同影響。並唔係呢份paper 做得唔好 只是需要更多research 去證實。 paper 其實有寫: - eg “In five trials with 598 participants exposed to short periods of extreme physical stress (including marathon runners and skiers) vitamin C halved the common cold risk.” 50%其實唔細, 但係未必能套用到general public - eg "Trials of high doses of vitamin C administered therapeutically, starting after the onset of symptoms, showed no consistent effect on the duration or severity of common cold symptoms. However, only a few therapeutic trials have been carried out and none have examined children, although the effect of prophylactic vitamin C has been greater in children." - eg "More trials are necessary to settle the possible role of therapeutic vitamin C, meaning administration immediately after the onset of symptoms." 所以paper嘅結論係未知, 有待更多研究confirm 另外,clinical 同 research 雖然是相輔相成, 但並唔係research = 跟足,更何況只是review, 唔係 guideline 我明白不是每個人都有research/clinical background, 但希望皮毛小知識下次可以睇仔細d再出片,尤其係health-related。 好欣賞你咁有心機講解同剪片, 希望能再接再厲。:)
Cochrane 作者conclusion明明話regular supplementation有效, vit C 又平又SAFE; common cold病人可以按情況試食. 你選擇性無視? 仲有唔好用confidence interval 個 lower limit 3% 做文章, for adults個pooled effect係 7.7% (3.7% - 12%). EFFECT = 8% 呀, 唔係你不停(錯誤)引用嘅3% (明明3.7四捨五入係4%) 'Nevertheless, given the consistent effect of vitamin C on common cold duration and severity in the regular supplementation studies, and the low cost and safety, it may be worthwhile for common cold patients to test on an individual basis whether therapeutic vitamin C is beneficial for them.'