Cole et al (2003) sent a letter of invitation accompanied by an information sheet on screening for colorectal cancer and a stool sample collection kit with relevant instructions. Reminders were sent by mail six weeks after the initial mail-out if a completed collection card had not been received. Participants were advised of the results (positive or negative).

In Hol et al studies (2010) same population, and two different studies, all individuals were sent a pre-invitation letter containing information on CRC screening. All information was made available via a dedicated website (www.dikkedarmkankerpreventie.nl; accessed 3 September 2009), mailings and information sites of the municipality offices, regional newspapers and national and regional broadcasting.

In the Israeli study by Levi et al. (2011) those willing to participate were instructed how to prepare the FOBTs and were asked to bring it back to the clinic. The kits were then transported to a central laboratory. The patients with positive tests were referred to a consultant gastroenterologist with a recommendation to perform colonoscopy. Hemoccult SENSATM (HOS) Cards were provided at the primary care clinic. Patients willing to participate in the study received an oral explanation and written instructions about test preparation. Patients were requested to follow the manufacturer’s instructions on diet and use of medications before and during the preparation for G-FOBT. They applied stool on six windows of three cards and brought them back to the clinic where they were provided. Then, the cards were collected and checked at the central laboratory of the CHS. OC-MICRO (FIT) This FIT: 14 Patients willing to participate in the study received an oral explanation and written instructions about the test preparation. They were given the kit for fecal sampling and requested to prepare three consecutive daily samples without any limitation of diet or medication. The patients were instructed to keep the samples in the refrigerator and bring the samples back to the clinic using a cooling bag provided with the kits. Samples were refrigerated at 4 C until developed within 2 weeks of preparation.

Birkenfeld study (2011) verbal explanation and written instructions about the test preparations were given. Individuals received a kit for faecal sampling and were requested to prepare three consecutive daily samples without any limitation of diet or medications. In the FIT arm participants were instructed to keep the samples in their refrigerator and bring the samples back to the clinic using a cooling bag provided with the kits. For FOBT, participants were provided with cards (Hemoccult SENSATM, Beckman Coulter, Fullerton, CA) at the primary care clinic and were requested to follow the manufacturer’s instructions on diet and use of medications before and during preparation of the gFOBT. They applied stool on six windows of three cards and brought the cards back to their clinic. The cards were then collected. Participants in the study received a verbal explanation and written instructions about the test preparations. They received a kit for faecal sampling and were requested to prepare three consecutive daily samples without any limitation of diet or medications.  Participants were instructed to keep the samples in their refrigerator and bring the samples back to the clinic using a cooling bag provided with the kits. The samples were refrigerated at 4oC. All individuals participating to the whole study were informed and asked whether they wanted to participate, but did not have to sign an informed consent.