Apr 13

Is vitamin C effective in treating the common cold?

Journal reference: Hemilä H, Chalker E, Douglas B. Vitamin C for preventing and treating the common cold. Cochrane Database of Systematic Reviews 2007, Issue 3. Art. No.: CD000980.

Link: http://dx.doi.org/10.1002/14651858.CD000980.pub3

Published: 18 July 2007

Evidence cookie says…

Oral vitamin C is not an effective treatment for the common cold in the general community.

There is good evidence that vitamin C prophylaxis does not reduce the incidence of colds, but does appear to have a modest effect on the duration and severity of an episode.

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Dec 09

How can we treat hangovers?

Journal reference: Pittler MH, Verster JC, Ernst E. Interventions for preventing or treating alcohol hangover: systematic review of randomised controlled trials. BMJ 2005; 331: 1515

Link: http://dx.doi.org/10.1136/bmj.331.7531.1515

Published: 22 December 2005

Evidence cookie says…

There is no convincing evidence of the effectiveness of any hangover treatments.

The only known effective way to avoid alcohol hangover is to drink sensibly.

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Nov 30

GP Synergy EBM Online Course

I have been working on an online EBM and critical appraisal teaching program for GP registrars at GP Synergy this year.  The online course is finally complete!

This program will take 4-5 hours to complete, but is divided into a number of separate modules. The modules use an online presentation platform, and you will need a modern browser (e.g., Firefox 7+, Chrome 14+, Safari, Internet Explorer 9+) on a Windows PC or Mac. Your computer will need broadband internet access.

This program uses elements from the free online course; Understanding Evidence-Based Healthcare: A Foundation for Action – Course for Physicians, that is developed and maintained by the US Cochrane Center at the Johns Hopkins Bloomberg School of Public Health. Special acknowledgement must go to the Center who gave permission for their course to be used. You should feel free to complete the entire Cochrane Center course if you want more detailed teaching in evidence-based medicine.

The GP Synergy EBM Online Course can be found here: http://tiny.cc/ebm4gp

I welcome any comments that will help improve this teaching resource.

Oct 24

Is cryotherapy the best treatment for common warts?

Journal reference: Bruggink SC, Gussekloo J, Berger MY, et al. Cryotherapy with liquid nitrogen versus topical salicylic acid application for cutaneous warts in primary care: randomized controlled trial. CMAJ 2010; 182(15): 1624-30

Link: http://dx.doi.org/10.1503/cmaj.092194

Published: 13 September 2010

Evidence cookie says…

Liquid nitrogen cryotherapy is likely more effective than topical salicyclic acid for the treatment of common warts in primary care.

Note: the authors used a “high intensity” application of cryotherapy, which may be more intensive than typical in general practice.

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Sep 11

GPET Convention workshop: EBM journal clubs

I ran a workshop on Thursday 8 September 2011, at the General Practice Education and Training (GPET) 2011 Convention on Evidence-based journal clubs for professional development.  The presentation can be viewed online (through prezi.com).  A warm thank you to Dr Sjoerd Bruggink for allowing me to use his study published in 2010 for a critical appraisal group exercise. Continue reading

Aug 19

Can cranberry prevent UTIs?

Journal reference: Barbosa-Cesnik C, Brown MB, Buxton M, et al. Cranberry juice fails to prevent recurrent urinary tract infection: results from a randomised placebo-controlled trial. Clinical Infectious Diseases 2011; 52(1): 23-30

Link: dx.doi.org/10.1093/cid/ciq073

Published: 1 January 2011

Evidence cookie says…

Cranberry juice is unlikely to be an effective prophylactic for recurrent urinary tract infections in young women.

This was a well-designed, pragmatic clinical trial.

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Jun 22

Dabigatran versus warfarin for atrial fibrillation

Journal reference: Connolly SJ, Ezekowitz MD, Yusuf S, et al. Dabigatran versus warfarin in patients with atrial fibrillation. N Engl J Med 2009; 361:1139-1151 [1]

Link: http://dx.doi.org/10.1056/NEJMoa0905561

Published: 17 September 2009

Evidence cookie says...

Dabigatran (Pradaxa) is non-inferior to warfarin for the prevention of strokes or systemic embolism, in non-valvular atrial fibrillation. 

Its effectiveness and safety has not been demonstrated in patients with severe renal impairment or active liver disease (excluded).

The benefits (↓ major bleeding and ↓ stroke) from dabigatran should be balanced against the harms (↑ myocardial infarction and ↑ gastrointestinal bleeding).

The study design may have biased results favourably towards dabigatran.

Note: dabigatran is not currently funded by the PBS for this indication.

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May 11

Type 2 diabetes and increased risk for malaria

Journal reference: Danquah I, Bedu-Addo G, Mockenhaupt F. Type 2 diabetes mellitus and increased risk for malaria infection. Emerg Inf Dis 2010; 16 (1): 1601-1604 [1]

Link: http://dx.doi.org/10.3201/eid1610.100399

Published: October 2010

Evidence cookie says...

There may be an association between type 2 diabetes and malaria infection

The evidence is low in quality and unreliable.

Nevertheless, this finding reinforces current travel advice for travellers to malaria endemic regions (mosquito avoidance, protective clothing, chemoprophylaxis).

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May 04

Inhaled corticosteroids as rescue treatment

Journal reference: Martinez FD, Chinchilli VM, Morgan WJ, et al. Use of beclomethasone dipropionate as rescue treatment for children with mild persistent asthma (TREXA): a randomised, double-blind, placebo-controlled trial. Lancet 2011; 377: 650–57 [1]

Link: http://dx.doi.org/10.1016/S0140-6736(10)62145-9

Published: 19 February 2011

Evidence cookie says...

Children with mild persistent asthma should be treated with regular inhaled corticosteroids. 

Treatment with salbutamol (Ventolin) alone significantly increases the risk of exacerbations.

Inhaled beclomethasone (Qvar) used as rescue therapy with salbutamol is likely better than salbutamol alone, for children with mild persistent asthma who do not take regular inhaled corticosteroids.

Note: the study is relatively underpowered.

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Apr 27

Zinc for the common cold

Journal reference: Singh M, Das RR. Zinc for the common cold. Cochrane Database of Systematic Reviews 2011, Issue 2. Art. No.: CD001364 [1]

Link: http://dx.doi.org/10.1002/14651858.CD001364.pub3

Published: 16 February 2011

Evidence cookie says...

Zinc administered within 24 hours of the symptoms of a common cold is associated with favourable outcomes but with some side-effects. 

  • ↓ cold symptom duration by ~ 1 day
  • ↓ cold symptom severity (minimal)
  • ↑ side-effects: bad taste (NNH = 7) and nausea (NNH = 12)

It is premature to routinely recommend zinc therapy for the common cold. It is reasonable to direct patients seeking community remedies towards zinc rather than other common treatments (echinacea, vitamin C).

Note: there are limitations to the evidence. See below for more details.

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