title: The knowledge of colorectal cancer symptoms and risk factors among 10,078 screening participants: are high risk individuals more knowledgeable?
abstract: OBJECTIVE
  We tested the a priori hypothesis that self-perceived and real presences of risks for colorectal cancer (CRC) are associated with better knowledge of the symptoms and risk factors for CRC, respectively.
  
  
  METHODS
  One territory-wide invitation for free CRC screening between 2008 to 2012 recruited asymptomatic screening participants aged 50-70 years in Hong Kong. They completed survey items on self-perceived and real presences of risks for CRC (advanced age, male gender, positive family history and smoking) as predictors, and knowledge of CRC symptoms and risk factors as outcome measures, respectively. Their associations were evaluated by binary logistic regression analyses.
  
  
  RESULTS
  From 10,078 eligible participants (average age 59 years), the mean knowledge scores for symptoms and risk factors were 3.23 and 4.06, respectively (both score range 0-9). Male gender (adjusted odds ratio [AOR] = 1.34, 95% C.I. 1.20-1.50, p<0.01), self-perception as not having any risks for CRC (AOR = 1.12, 95% C.I. 1.01-1.24, p = 0.033) or uncertainty about having risks (AOR = 1.94, 95% C.I. 1.55-2.43, p<0.001), smoking (AOR 1.38, 95% C.I. 1.11-1.72, p = 0.004), and the absence of family history (AOR 0.61 to 0.78 for those with positive family history, p<0.001) were associated with poorer knowledge scores (≤ 4) of CRC symptoms. These factors remained significant for knowledge of risk factors.
  
  
  CONCLUSIONS
  Male and smokers were more likely to have poorer knowledge but family history of CRC was associated with better knowledge. Since screening of these higher risk individuals could lead to greater yield of colorectal neoplasm, educational interventions targeted to male smokers were recommended.
authors.affiliation: Institute of Digestive Disease, Faculty of Medicine, Chinese University of Hong Kong, Hong Kong SAR, China.
authors.forename: Martin C S
authors.initials: MC
authors.lastname: Wong
authors.forename: Hoyee W
authors.initials: HW
authors.lastname: Hirai
authors.forename: Arthur K C
authors.initials: AK
authors.lastname: Luk
authors.forename: Thomas Y T
authors.initials: TY
authors.lastname: Lam
authors.forename: Jessica Y L
authors.initials: JY
authors.lastname: Ching
authors.forename: Sian M
authors.initials: SM
authors.lastname: Griffiths
authors.forename: Francis K L
authors.initials: FK
authors.lastname: Chan
authors.forename: Joseph J Y
authors.initials: JJ
authors.lastname: Sung
mesh_terms: D000368:Aged; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D055088:Early Detection of Cancer; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D012307:Risk Factors; D011795:Surveys and Questionnaires