Validation of self-reported endometriosis

Dereje G Gete; Annette J Dobson; Sally Mortlock; Grant W Montgomery; Richard Hockey; Jenny Doust; Gita D Mishra

doi:10.1016/j.maturitas.2025.108642

Validation of self-reported endometriosis

Maturitas. 2025 Jun 18:199:108642. doi: 10.1016/j.maturitas.2025.108642. Online ahead of print.

Authors

Dereje G Gete¹, Annette J Dobson², Sally Mortlock³, Grant W Montgomery⁴, Richard Hockey⁵, Jenny Doust⁶, Gita D Mishra⁷

Affiliations

¹ Australian Women and Girls' Health Research Centre, School of Public Health, The University of Queensland, 11 Wyndham Street, Brisbane, Queensland 4006, Australia. Electronic address: d.gete@uqconnect.edu.au.
² Australian Women and Girls' Health Research Centre, School of Public Health, The University of Queensland, 11 Wyndham Street, Brisbane, Queensland 4006, Australia. Electronic address: a.dobson@sph.uq.edu.au.
³ Australian Women and Girls' Health Research Centre, School of Public Health, The University of Queensland, 11 Wyndham Street, Brisbane, Queensland 4006, Australia. Electronic address: s.mortlock@imb.uq.edu.au.
⁴ Institute for Molecular Bioscience, The University of Queensland, 306 Carmody Road, Brisbane, Queensland 4072, Australia. Electronic address: g.montgomery1@uq.edu.au.
⁵ Australian Women and Girls' Health Research Centre, School of Public Health, The University of Queensland, 11 Wyndham Street, Brisbane, Queensland 4006, Australia. Electronic address: r.hockey@uq.edu.au.
⁶ Australian Women and Girls' Health Research Centre, School of Public Health, The University of Queensland, 11 Wyndham Street, Brisbane, Queensland 4006, Australia. Electronic address: j.doust@uq.edu.au.
⁷ Australian Women and Girls' Health Research Centre, School of Public Health, The University of Queensland, 11 Wyndham Street, Brisbane, Queensland 4006, Australia. Electronic address: g.mishra@uq.edu.au.

PMID: 40540999
DOI: 10.1016/j.maturitas.2025.108642

Abstract

Objectives: To assess the validity and reliability of self-reported diagnoses of endometriosis.

Study design: The study included 8572 women from two Australian birth cohorts (1989-95 and 1973-78), using data from the Genetic variants, Early Life exposures, and Longitudinal Endometriosis Symptoms Study (GELLES), a sub-study of the Australian Longitudinal Study on Women's Health. Validity was assessed using predictive values, and reliability was evaluated with kappa statistics.

Main outcome measures: Self-reported endometriosis diagnoses from the GELLES question "Has a doctor or healthcare provider ever diagnosed you with endometriosis?" were validated using a longitudinal survey and linked administrative records as the gold standard.

Results: The findings from the 1989-95 and 1973-78 cohorts showed good agreement for overall self-reported endometriosis diagnosis, with uncorrected kappa values of 0.67 and 0.70 (or 0.86 and 0.83 after correction for bias and prevalence effects), and positive predictive values of 0.75 and 0.84, respectively. The agreement was notably stronger for self-reported surgical diagnoses, with uncorrected kappa values of 0.87 and 0.79, and positive predictive values of 0.84 and 0.85, respectively. However, the validity of clinically suspected diagnoses was lower due to the higher occurrence of discrepancies in case assignments.

Conclusions: The findings indicate that self-reported endometriosis obtained from two questions about diagnoses made by doctors and specified methods (surgical or clinical) are valid and reliable, particularly for surgical diagnoses. Women's responses to these questions can be reliable for identifying endometriosis cases in epidemiological research. Self-reported data of clinically suspected diagnoses (i.e. without surgical confirmation) should be interpreted cautiously.

Keywords: Administrative health data; Endometriosis; Longitudinal survey; Self-report; Validity.