Patient-reported outcome measures for acne: a mixed-methods validation study (acne PROMs)

Samantha Hornsey; Beth Stuart; Ingrid Muller; Alison M Layton; Leanne Morrison; Jamie King; Karen Thomas; Paul Little; Miriam Santer

doi:10.1136/bmjopen-2019-034047

Patient-reported outcome measures for acne: a mixed-methods validation study (acne PROMs)

BMJ Open. 2021 Mar 19;11(3):e034047. doi: 10.1136/bmjopen-2019-034047.

Authors

Samantha Hornsey¹, Beth Stuart², Ingrid Muller², Alison M Layton^{3

4}, Leanne Morrison^{2

5}, Jamie King², Karen Thomas⁶, Paul Little², Miriam Santer²

Affiliations

¹ Faculty of Medicine, Primary Care, Population Sciences and Medical Education, University of Southampton, Southampton, Hampshire, UK sh7g13@soton.ac.uk.
² Faculty of Medicine, Primary Care, Population Sciences and Medical Education, University of Southampton, Southampton, Hampshire, UK.
³ Department of Dermatology, Harrogate and District NHS Foundation Trust, Harrogate, North Yorkshire, UK.
⁴ School of Medicine, Hull York Medical School, York, UK.
⁵ Department of Psychology, University of Southampton, Southampton, UK.
⁶ Faculty of Medicine, Primary Care, Population Sciences and Medical Education, PPI Representative, University of Southampton, Southampton, UK.

Abstract

Objectives: To examine the acceptability and validity of two patient-reported outcome measures (PROMs) for adult acne, comparing them to the validated Acne-specific Quality of Life (Acne-QoL) measure.

Design: Mixed-methods validation study.

Setting: Participants were recruited by (1) mail-out through primary care if they had ever consulted for acne and received a prescription for acne treatment within the last 6 months, (2) opportunistically in secondary care and (3) poster advertisement in community venues.

Participants: 221 (204 quantitative and 17 qualitative) participants with acne, aged 18-50 years.

Outcome measures: Quantitative sub-study participants completed Acne-QoL, Skindex-16 and Comprehensive Acne Quality of Life Scale (CompAQ) at baseline, 24 hours and 6 weeks. Qualitative sub-study participants took part in cognitive think-aloud interviews, while completing the same measures. Transcribed audio recordings were analysed using inductive thematic analysis.

Results: Quantitative analyses suggested high internal consistency (Cronbach's alpha 0.74-0.96) and reliability (intraclass correlation coefficient values 0.88-0.97) for both questionnaires. Both scales showed floor effects on some subdomains. Skindex-16 and CompAQ showed good evidence of construct validity when compared with Acne-QoL with Spearman's correlation coefficients 0.54-0.81, and good repeatability over 24 hours.Qualitative data uncovered wide-ranging views regarding usability and acceptability. Interviewees held strong but differing views about layout, question/response wording, redundant/similar questions and guidance notes. Similarly, interviewees differed in perceptions of acceptability of the different scales, particularly on relatability of questions and emotive reactions to scales.

Conclusions: All PROMs performed well in statistical analyses. No PROM showed superior usability and acceptability in the qualitative study. Any PROM should be acceptable for further research in adult acne but researchers should consider the different domains and whether they will measure only facial or facial and trunk acne before making a selection. A new PROM or further evaluation of novel PROMs may be beneficial.

Keywords: acceptability; acne; adult; adult dermatology; patient reported outcome measures; validity.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Acne Vulgaris* / drug therapy
Adolescent
Adult
Humans
Middle Aged
Patient Reported Outcome Measures
Quality of Life*
Reproducibility of Results
Surveys and Questionnaires
Young Adult