title: Development and validation of the Intrinsic Religiousness Inventory (IRI).
abstract: OBJECTIVE
  The role of religious involvement in mental health has been increasingly investigated in psychiatric research; however, there is a shortage of scales on religiousness in Portuguese. The present study aimed to develop and validate a brief instrument to assess intrinsic religiosity (Intrinsic Religiousness Inventory - IRI) in two Brazilian samples.
  
  
  METHODS
  The initial version was based on literature review and experts' suggestions. University students (sample 1; n = 323) and psychiatric patients (sample 2; n = 102) completed the Duke Religiosity Index (DUREL), the IRI, an instrument of spirituality measurement (WHOQOL-SRPB), as well as measurements of anxiety and depressive symptoms.
  
  
  RESULTS
  The IRI showed adequate internal consistence reliability in sample 1 (Cronbach's α = 0.96; 95% CI; 0.95-0.97) and sample 2 (α = 0.96; 95% CI; 0.95-0.97). The IRI main component analyses indicated a single factor, which explained 73.7% and 74.9% of variance in samples 1 and 2, respectively. Strong correlations between IRI and intrinsic subscale of the DUREL were observed (Spearman's r ranging from 0.87 to 0.73 in samples 1 and 2, respectively, p < 0.001). The IRI showed good test-retest reliability (intraclass correlation coefficients > 0.70).
  
  
  CONCLUSIONS
  These data indicate that the IRI is a valid instrument and may contribute to study intrinsic religiosity in Brazilian samples.
authors.affiliation: Postgraduate Program in Health Sciences, Faculty of Medicine, Universidade Federal do Ceará, Fortaleza, Brazil.
authors.forename: Tauily C
authors.initials: TC
authors.lastname: Taunay
authors.forename: Eva D
authors.initials: ED
authors.lastname: Cristino
authors.forename: Myrela O
authors.initials: MO
authors.lastname: Machado
authors.forename: Francisco H
authors.initials: FH
authors.lastname: Rola
authors.forename: José W O
authors.initials: JW
authors.lastname: Lima
authors.forename: Danielle S
authors.initials: DS
authors.lastname: Macêdo
authors.forename: Francisco de Assis A
authors.initials: Fde A
authors.lastname: Gondim
authors.forename: Alexander
authors.initials: A
authors.lastname: Moreira-Almeida
authors.forename: André F
authors.initials: AF
authors.lastname: Carvalho
mesh_terms: D000328:Adult; D001938:Brazil; D005260:Female; D006801:Humans; D008297:Male; D012067:Religion; D012069:Religion and Psychology; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires