title: Demographic and Life Styles Determinants of Somatic Complaints' Structures: A Cross-sectional Study on a Large Sample of Iranian Adults Using Factor Mixture Model.
abstract: BACKGROUND
  To identify somatic complaints dimensions, classify studied population and study the association of demographic and lifestyle factors with somatic complaints dimensions.
  
  
  METHODS
  In a cross-sectional study conducted on 4763 Iranian adults, somatic complaints were assessed using a comprehensive 30-item questionnaire. Self-administered standard questionnaires were used to assess demographic and lifestyle factors. Factor mixture modeling (FMM) was used to identify somatic complaints dimensions and classify studied population.
  
  
  RESULTS
  The mean age of participants was 36.58 ± 0.13 years, 55.8% were females, 81.2% were married, and 57.2% had college education. About 9.4% of individuals were obese, and 34.8% of participants had regular physical activity. Four domains of somatic complaints were extracted, including "psychological," "gastrointestinal," "neuro-skeletal," and "pharyngeal-respiratory." Females, obese and inactive participants, and those in low educations had significantly greater scores in terms of four domains than the others (P< 0.05). A two-class, four-factor structure fitted to the somatic complaints based on FMM. Two classes were labeled "high psychological complaints" (519 individuals (11%) and "low psychological complaints" (4243 individuals (89%). There were no significant differences between two classes in terms of demographic and lifestyle factors, except in educational level.
  
  
  CONCLUSIONS
  This study suggested that somatic complaints had a dimensional-categorical structure within studied population so that it could be useful for dealing with diagnostic and therapeutic approaches. The results did not show any association between somatic complaints dimensions and demographic, lifestyle factors, except in educational level.
authors.affiliation: Department of Biostatistics and Epidemiology, Student Research Center, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Heidari
authors.affiliation: Department of Biostatistics and Epidemiology, School of Health, Psychosomatic Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Awat
authors.initials: A
authors.lastname: Feizi
authors.affiliation: Cardiac Rehabilitation Research Center, Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Hamidreza
authors.initials: H
authors.lastname: Roohafza
authors.affiliation: Department of Medicine, University of Alberta, Edmonton, Alberta, Canada; Integrative Functional Gastroenterology Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Ammar Hassanzadeh
authors.initials: AH
authors.lastname: Keshteli
authors.affiliation: Department of Biostatistics and Epidemiology, Student Research Center, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Fatemeh Zahra
authors.initials: FZ
authors.lastname: Shiravi
authors.affiliation: Department of Internal Medicine, Integrative Functional Gastroenterology Research Center, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Payman
authors.initials: P
authors.lastname: Adibi
keywords: Demographic factors; factor mixture modeling; lifestyles; somatic complaints