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I agree with Zbys and Ahmed. Whether or not this process was truly random is unclear from the description. An equally important issue, and separate from randomisation (sequence generation), is concealment of allocation - whether the researchers had the opportunity to interfere with allocation following sequence generation. Again, there is inadequate information about whether allocation was protected from interference. Ideally, clarification should be sought from the protocol, then the study authors, as Ahmed suggests. There is no information about blinding here - not to be confused with concealment of allocation. For example, treatment assignment could have been performed by research workers separate from the treating clinicians, and a degree of blinding achieved. Michele From: Evidence based health (EBH) [mailto:[log in to unmask]] On Behalf Of Dr. Ahmed M. Abou-Setta Sent: 02 July 2013 02:52 To: [log in to unmask] Subject: Re: randomisation I will have to disagree here... I'm not saying that this is a correct form of randomization, but rather it is an unclear form of randomization until we know more. The authors stated "We assigned participants to two groups by randomized sequential allocation. The first patient was randomly assigned to the LC group by tossing a coin, the second patient to the AB group, and the other patients were assigned to the two groups, sequentially." From this we can tell the following: A) 1st patient was properly randomized. B) 2nd patient was not quasi-randomized - unless they entered two patients in the study at the same time. C) Every patient after that may or may not have been properly randomized depending on whether or not they kept flipping coins or whether they used alternate randomization. This is the gray area where published protocols and contacting authors for additional information/ clarification comes in handy. In this case the protocol (http://www.irct.ir/searchresult.php?id=1658&number=1) doesn't help much. So the only remaining options are to either make a decision based on what is available in the published trial report or contact the author. Ahmed ________________________________ Date: Mon, 1 Jul 2013 20:57:35 -0400 From: [log in to unmask]<mailto:[log in to unmask]> Subject: Re: randomisation To: [log in to unmask]<mailto:[log in to unmask]> Hi Mark, I agree with Valerie, it also appears this study was not blinded. We did a post http://www.ithinkwell.org/why-is-randomization-needed-in-clinical-trials/ and there is an excellent paper on this embedded written by Jeremy Howick and a great 5 minute video supplied by Dr Terry Shanyfelt. In the comments Paul Lucas has made some astute observations and even uses an autologous example, I hope this could be helpful , The guidelines I like best for RCTs and systematic reviews come from a program called CASP they are 10-11 point checklists with full explanations and are a great way to see what you have in a simple and fair way, they are free to download here under checklists http://www.casp-uk.net/ `I always try to give pers a pass but sometimes you just cant! Best Amy From: Valerie King <[log in to unmask]<mailto:[log in to unmask]>> Reply-To: Valerie King <[log in to unmask]<mailto:[log in to unmask]>> Date: Monday, July 1, 2013 8:29 PM To: <[log in to unmask]<mailto:[log in to unmask]>> Subject: Re: randomisation In a word, no. Could someone predict which group the next subject would be allocated to? Yes. Could that someone therefore not enroll said subject, or consent for enrollment differently, or hold off on enrollment, or some other action in order to get the subject the care that the someone really wanted or the subject really wanted? Of course, that someone could do those things. Therefore it isn't adequate randomisation. Valerie J. King, MD, MPH Director of Evidence and Policy Center for Evidence-based Policy Oregon Health & Science University Mailcode SN-4N 3455 SW US Veterans Hospital Rd. Portland, OR 97239 Voice: 503-494-8694 Fax: 503-494-3807 [log in to unmask]<mailto:[log in to unmask]> www.ohsu.edu/policycenter/<http://www.ohsu.edu/policycenter/> From: Evidence based health (EBH) [mailto:[log in to unmask]] On Behalf Of Mark Ayson Sent: Monday, July 01, 2013 5:05 PM To: [log in to unmask]<mailto:[log in to unmask]> Subject: randomisation Dear group I was wondering if you could help me. I am working on a report about autologous blood injections and have an RCT that describes their randomisation technique as follows: "We assigned participants to two groups by randomized sequential allocation. The first patient was randomly assigned to the LC group by tossing a coin, the second patient to the AB group, and the other patients were assigned to the two groups, sequentially." Is this techniques an adequate method of randomisation? I look forward to your comments. Kind regards Mark Mark Ayson, MBChB, DPH Research Advisor, Governance, Policy & Research, ACC Tel 04-8166386 / Fax 04-8167562 / Ext 46386 ACC / Research / Vogel House, 19 Aitken Street PO Box 242 / Wellington 6011 / New Zealand / www.acc.co.nz<http://www.acc.co.nz/> ACC cares about the environment - please don't print this email unless it is really necessary. Thank you. ________________________________ Disclaimer: "This message and any attachments may contain confidential and privileged information. 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