A medical site worth visiting is Bandolier's website . Bandolier independently scrutinises the evidence base in health, health care and medicine - that is to show what works and what does not.
The tables presented in this link will show you the evidence base and success of the medical treatment of some common conditions. Please pay specific attention to a factor called NNT, which is the number of patients who need to be treated to prevent one bad outcome.
For instance take Bandolier's first example:
If infection of the middle ear was treated with antibiotics for a short term, an NNT of 7 would mean that seven patients would have to be treated to make one patient free of signs and symptoms within 7-14 days.
This means that the success rates for
- 50% improvement of acute sprains using non steroidal anti inflammatory treatments (eg aspirin, ibuprofen etc) is one in two cases. Three out of four patients are likely to experience less than 50% pain relief.
- 3-8 weeks of glucosamine supplementation helps about one in 5 patients symptomatically.
- A spinal epidural helps one in 6 back pain patients to 75% pain relief after 2 months. (Back pain here refers to mechanical sprain/strian type of injuries).
- Flu prevention following vaccination occurs with a likelihood of about 4%. 23 patients have to be vaccinated to prevent one case of flu from happening.
Is exposure to sunlight harmful?
Although in Britain we may not have had the hottest of summers these days the glowing debate about whether sunlight is bad or good for us has continued in the papers. I cannot recall a recent medical issue that has been presented to the public in such contradicting ways. One camp says we have to hide ourselves away away from the sun and its damaging UVA and UVB rays. Exposure to sunlight is said to cause skin ageing, mutation to our DNA and deadly skin cancer (malignant melanoma - reported to be on the rise in Britain like never before). Open the newspaper the next day we are advised by the opposite school of thought that moderate exposure to sunlight bears essential health beneficial proven to help us against cardiac disease, diabetes, soft and brittle bone disease - and skin cancer!
The evidence of whether sunlight (or maybe something else) causes these alarming rates of skin cancer needs to be scrutinised.
First study to support cancer link
The first claim that UVB found in sunlight was thought to be related to the evolution of malignant melanoma was made in the May 1998 issue of the American Journal of Pathology. Lead by dermatologist Ercem Atillasoy research was conducted. Mice, grafted with human skin were exposed to UV light for various amounts of time over 10 months. Atillasoy et al found that the human skin graft blistered following prolonged radiation and noted that out of 158 irradiated mice one human skin graft would develop a nodular malignant melanoma (the skin was also treated with 7,12-dimethyl(a)benzanthracene).
The study concluded that there was now "first clear evidence that UVB exposure is directly linked to the development of melanoma" and that it was critical that people "avoid the sun and use sun protection methods, such as sunscreen, every day." However, the research team was surprised that in a follow up study on irradiating human skin transplanted onto immune-deficient mice with UVB light the most common skin cancer, basal cell carcinoma, did not develop. But as for melanoma it was decided that specific wavelength as well as the dosage and timing of exposure was a definate causative factor for the development of skin cancer in humans.
Here you find Cancer Research UK's recommendations on the prevention of skin cancer.
Is the truth really as simple as that? Read about the shortfalls of the original research . Learn about the important role of Vitamin D and its role in the prevention of skin cancer .
