The UK Faculty of Public Health has recently taken ownership of the Health Knowledge resource. This new, advert-free website is still under development and there may be some issues accessing content. Additionally, the content has not been audited or verified by the Faculty of Public Health as part of an ongoing quality assurance process and as such certain material included maybe out of date. If you have any concerns regarding content you should seek to independently verify this.

Further Resources



The following journal articles and books are useful if you want to learn more about the design or critical appraisal of randomised controlled trials.

Randomised controlled trials

Schulz KF, Grimes DA. Allocation concealment in randomised trials: defending against deciphering. Lancet 2002 Feb 16;359(9306):614-8
Schulz KF, Grimes DA. Generation of allocation sequences in randomised trials: chance, not choice. Lancet 2002 Feb 9;359(9305):515-9
Schulz KF, Grimes DA. Multiplicity in randomised trials II: subgroup and interim analyses. Lancet 2005 May 7;365(9471):1657-61
Schulz KF, Grimes DA. Multiplicity in randomised trials I: endpoints and treatments. Lancet 2005 Apr 30;365(9470):1591-5.

Sample size in RCTs

Schulz KF, Grimes DA. Unequal group sizes in randomised trials: guarding against guessing. Lancet 2002 Mar 16;359(9310):966-70
Schulz KF, Grimes DA. Sample size slippages in randomised trials: exclusions and the lost and wayward. Lancet 2002 Mar 2;359(9308):781-5
Schulz KF, Grimes DA. Sample size calculations in randomised trials: mandatory and mystical. Lancet 2005 Apr 9;365(9467):1348-53