References
- Amy JJ. Evidence-based medicine: The salad is only as good as the ingredients. Eur J Contracept Reprod Health Care 2013;18:323–6.
- Helmerhorst FM, Belfield T, Kulier R, et al. The Cochrane Fertility Regulation Group: synthesizing the best evidence about family planning. Contraception 2006;74:280–6.
- http://fertility-regulation.cochrane.org/
- Vandenbroucke JP. When are observational studies as credible as randomised trials? Lancet 2004;363: 1728–31.
- Cushman M, Kuller LH, Prentice R, et al; Women's Health Initiative Investigators. Estrogen plus progestin and risk of venous thrombosis. JAMA 2004;292:1573–80.
- Golder S, Loke YK, Bland M. Meta-analyses of adverse effects data derived from randomised controlled trials as compared to observational studies: Methodological overview. PLoS Med 2011;8:e1001026.
- Atkins D, Best D, Briss PA, et al; GRADE Working Group. Grading quality of evidence and strength of recommendations. BMJ 2004;328:1490.
- www.equator-network.org/reporting-guidelines/the-strengthening-the-reporting-of-observational-studies-in-epidemiology-strobe-statement-guidelines-for-reporting-observational-studies/