title: Relation between demographic factors and type of gastrointestinal cancer using probit and logit regression.
abstract: BACKGROUND
  Approximately 50,000 new cases of cancer occur each year in the Iranian population of 70.4 million. The organ system involved with more than 38% of all cancers is the gastrointestinal (GI) tract. The objective of this study was to investigate the relation between demographic factors and type of gastrointestinal cancer using probit and logit models.
  
  
  METHODS
  This study was designed as a cross-sectional survey including all consecutive GI cancer patients admitted over a one year period in a randomly selected hospital group located in Tehran in 2006.
  
  
  RESULTS
  The largest number of cases were colorectal cancers (40.0%), followed by gastric cancers (34.5%) and esophagus cancers (17.1%). There was a significant gender effect in the colorectal, gastric and esophagus cancer also there was a significant association between age and gastrointestinal cancers in both logit and probit regression. The factor of duration was not significant in gastric cancer.
  
  
  CONCLUSIONS
  Men are more likely have colorectal cancer than women. Older people are more likely to have gastric cancer than younger people. For esophagus cancer all factors were significant. Results from probit and logit models were similar, indicating that probit analysis can be employed as a logit model to analyze relationships between demographic factors and cancer type.
authors.affiliation: Research Center of Gastroenterology and Liver Diseases, Shahid Beheshti University, (MC), Tehran, Iran.
authors.forename: Asma
authors.initials: A
authors.lastname: Pourhoseingholi
authors.forename: Mohamad Amin
authors.initials: MA
authors.lastname: Pourhoseingholi
authors.forename: Mohsen
authors.initials: M
authors.lastname: Vahedi
authors.forename: Azadeh
authors.initials: A
authors.lastname: Safaee
authors.forename: Bijan
authors.initials: B
authors.lastname: Moghimi-Dehkordi
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Ghafarnejad
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Zali
mesh_terms: D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000453:epidemiology; D003430:Cross-Sectional Studies; D004067:Digestive System Neoplasms / Q000175:diagnosis* / Q000453:epidemiology*; D004938:Esophageal Neoplasms / Q000175:diagnosis / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D007492:Iran / Q000453:epidemiology; D008113:Liver Neoplasms / Q000175:diagnosis / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D010190:Pancreatic Neoplasms / Q000175:diagnosis / Q000453:epidemiology; D011336:Probability; D018570:Risk Assessment; D013274:Stomach Neoplasms / Q000175:diagnosis / Q000453:epidemiology; D015996:Survival Rate