ART Cohort Collaboration
http://www.art-cohort-collaboration.org/

BMI Healthy Weight Calculator (NHS)
http://www.nhs.uk/Tools/Pages/Healthyweightcalculator.aspx?Tag

British National Formulary (BNF)
http://www.bnf.org/

Cardiovascular Risk Calculator (University of Edinburgh)
http://cvrisk.mvm.ed.ac.uk/calculator/calc.asp

CASCADE Risk Calculator
http://www.ctu.mrc.ac.uk/cascade/risk_calculator.asp

CHIVA guidelines
http://www.chiva.org.uk/professionals/health/guidelines/index.html

eGFR Calculator (The Renal Association)
http://www.renal.org/eGFRcalc/GFR.pl

electronic Medicines Compendium (eMC)
http://emc.medicines.org.uk/

HIV Drug Resistance Database (Stanford University)
http://hivdb.stanford.edu/

HIVdb Program: Mutation List Analysis (Stanford University)
http://hivdb.stanford.edu/pages/algs/sierra_mutation.html

Liverpool HIV Pharmacology Group (LHPG)
http://www.hiv-druginteractions.org/

National Electronic Library of Medicines (NHS NeLM)
http://www.nelm.nhs.uk/

National Institute for Health and Clinical Excellence (NICE)
http://www.nice.org.uk/

PubMed
http://www.ncbi.nlm.nih.gov/PubMed/

The Antiretroviral Pregnancy Registry
http://www.apregistry.com/

WHO Fracture Risk Assessment Tool (University of Sheffield)
http://www.shef.ac.uk/FRAX/tool.jsp?locationValue=1

National treatment guidelines:
BASHH STI guidelines - http://www.bashh.org/guidelines

Chronic kidney disease - http://guidance.nice.org.uk/CG73

Depression - http://guidance.nice.org.uk/CG23

Hypertension - http://guidance.nice.org.uk/CG34

Lipid modification - http://guidance.nice.org.uk/CG67