title: COMPI Fertility Problem Stress Scales is a brief, valid and reliable tool for assessing stress in patients seeking treatment.
abstract: Are the Copenhagen Multi-Centre Psychosocial Infertility research program Fertility Problem Stress Scales (COMPI-FPSS) a reliable and valid measure across gender and culture?
  
  
  
  The COMPI-FPSS is a valid and reliable measure, presenting excellent or good fit in the majority of the analyzed countries, and demonstrating full invariance across genders and partial invariance across cultures.
  
  
  
  Cross-cultural and gender validation is needed to consider a measure as standard care within fertility. The present study is the first attempting to establish comparability of fertility-related stress across genders and countries.
  
  
  
  Cross-sectional study. First, we tested the structure of the COMPI-FPSS. Then, reliability and validity (convergent and discriminant) were examined for the final model. Finally, measurement invariance both across genders and cultures was tested.
  
  
  
  Our final sample had 3923 fertility patients (1691 men and 2232 women) recruited in clinical settings from seven different countries: Denmark, China, Croatia, Germany, Greece, Hungary and Sweden. Participants had a mean age of 34 years and the majority (84%) were childless.
  
  
  
  Findings confirmed the original three-factor structure of the COMPI-FPSS, although suggesting a shortened measurement model using less items that fitted the data better than the full version model. While data from the Chinese and Croatian subsamples did not fit, all other counties presented good fit (χ2/df ≤ 5.4; comparative fit index ≥ 0.94; root-mean-square error of approximation ≤ 0.07; modified expected cross-validation index ≤ 0.77). In general, reliability, convergent validity, and discriminant validity were observed in all subscales from each country (composite reliability ≥ 0.63; average variance extracted ≥ 0.38; squared correlation ≥ 0.13). Full invariance was established across genders, and partial invariance was demonstrated across countries.
  
  
  
  Generalizability regarding the validation of the COMPI-FPSS cannot be made regarding infertile individuals not seeking treatment, or non-European patients. This study did not investigate predictive validity, and hence the capability of this instrument in detecting changes in fertility-specific adjustment over time and predicting the psychological impact needs to be established in future research.
  
  
  
  Besides extending knowledge on the psychometric properties of one of the most used fertility stress questionnaire, this study demonstrates both research and clinical usefulness of the COMPI-FPSS.
  
  
  
  This study was supported by European Union Funds (FEDER/COMPETE-Operational Competitiveness Program, and by national funds (FCT-Portuguese Foundation for Science and Technology) under the projects PTDC/MHC-PSC/4195/2012 and SFRH/BPD/85789/2012). There are no conflicts of interest to declare.
  
  
  
  N/A.
authors.affiliation: Faculty of Psychology and Education Sciences, University of Porto, 4200-135 Porto, Portugal.
authors.forename: Maria P
authors.initials: MP
authors.lastname: Sobral
authors.affiliation: Faculty of Psychology and Education Sciences, University of Porto, 4200-135 Porto, Portugal.|Center for Psychology at University of Porto, 4200-135 Porto, Portugal.
authors.forename: Maria E
authors.initials: ME
authors.lastname: Costa
authors.affiliation: Department of Public Health, University of Copenhagen, Section of Social Medicine, 1014 København K, Denmark.
authors.forename: Lone
authors.initials: L
authors.lastname: Schmidt
authors.affiliation: Faculty of Psychology and Education Sciences, University of Porto, 4200-135 Porto, Portugal mmartins@fpce.up.pt.|Center for Psychology at University of Porto, 4200-135 Porto, Portugal.
authors.forename: Mariana V
authors.initials: MV
authors.lastname: Martins
mesh_terms: D000328:Adult; D002681:China; D017523:Croatia; D003430:Cross-Sectional Studies; D003469:Culture; D016208:Databases, Factual; D003718:Denmark; D005260:Female; D005858:Germany; D006115:Greece; D006801:Humans; D006814:Hungary; D007246:Infertility / Q000523:psychology*; D008297:Male; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D013315:Stress, Psychological / Q000175:diagnosis* / Q000523:psychology; D011795:Surveys and Questionnaires; D013548:Sweden
keywords: cross-cultural comparison; fertility stress; measurement invariance; psychometric properties; reliability and validity