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 Internal and external validity of cluster randomised trials
Cluster randomised trials are essential for evaluating certain types of intervention, and there are often strong scientific reasons to conduct them. The extent to which investigators are designing and analysing these trials appropriately has improved, according to this systematic review of recent trials.

RAPID RESPONSES
Should we dump the metabolic syndrome? No

• Indispensable for some, meaningless for others ... but what about the patients?
• Not yet
• Dubious value from a public health perspective

Should we dump the metabolic syndrome? Yes

• Metabolic syndrome may not be dumped
• Metabolic syndrome and smoking