title: Trying to improve the compliance to colorectal cancer screening: a complex study design for a complex planning question.
abstract: The efficacy of faecal occult blood test as primary screening for colorectal cancer has been demonstrated. Screening programs, to be effective, should guarantee high compliance in the target population. The aim of this paper is to describe the design of three connected studies aimed at obtaining precise indications for planning a colorectal cancer screening program with high compliance. We designed a survey, with a randomised controlled trial nested within it, and a case-control study nested within that and defined by the results of the trial. The complex interconnection of studies reflects the aim to produce indications for an evidence-based planning of a public health program, which is itself, a complex phenomenon. The trial was designed to evaluate two different types of tests, Immunochemical and Guaiac, and two different providers, general practitioner and hospital, with a 2 x 2 factorial design. The randomization was performed at two different levels to minimize the loss of power: at the practice level for test type (cluster randomisation) and individual level for provider type.
authors.affiliation: Agency for Public Health, Latium Region, Via di S. Costanza, 53 Rome 00198, Italy. giorgirossi@asplazio.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Giorgi Rossi
authors.forename: Antonio
authors.initials: A
authors.lastname: Federici
authors.forename: Francesco
authors.initials: F
authors.lastname: Bartolozzi
authors.forename: Sara
authors.initials: S
authors.lastname: Farchi
authors.forename: Piero
authors.initials: P
authors.lastname: Borgia
authors.forename: Gabriella
authors.initials: G
authors.lastname: Guasticchi
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000517:prevention & control; D005260:Female; D006761:Hospitals; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods / Q000706:statistics & numerical data; D008875:Middle Aged; D009780:Occult Blood; D010349:Patient Compliance; D016730:Program Development; D016032:Randomized Controlled Trials as Topic / Q000379:methods*; D012107:Research Design; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires