Development of a New Patient-reported Outcome Measure to Evaluate Treatments for Acne and Acne Scarring: The ACNE-Q

A.F. Klassen; S. Lipner; M. O'Malley; N.M. Longmire; S.J. Cano; T. Breitkopf; C. Rae; Y.L. Zhang; A.L. Pusic


The British Journal of Dermatology. 2019;181(6):1207-1215. 

In This Article

Abstract and Introduction


Background: Psychosocial concerns represent important outcomes in studies of treatments for acne and acne scarring. Also important, but largely overlooked, is the concept of appearance.

Objectives: To design an acne-specific patient-reported outcome measure for acne and acne scarring.

Methods: We used a mixed-methods approach. Phase I involved 21 patient interviews that were audio-recorded, transcribed and coded. Concepts were identified and developed into scales that were refined through 10 cognitive interviews and input from 16 clinical experts. Phase II involved data collection at hospital and community-based dermatology clinics in Canada and the U.S.A. Eligible participants were aged 12 years and older with acne and/or acne scars on the face, chest and/or back. Rasch Measurement Theory (RMT) analyses were performed to examine psychometric properties.

Results: Phase I led to the development of seven scales that measure appearance of facial skin, acne (face, chest and back) and acne scars, acne-specific symptoms and appearance-related distress. In phase II, 256 patients completed the ACNE-Q. RMT analysis provided evidence that the items of each scale worked together conceptually and statistically. Most participants scored within the range of measurement for each scale (81·9–93·1%). Reliability was high, with person separation index values and Cronbach alpha values > 0·90 for the appearance scales, ≥ 0·87 for appearance-related distress and ≥ 0·75 for symptoms. Worse scores on appearance scales correlated with worse symptom scores and more appearance-related distress.

Conclusions: The ACNE-Q is a rigorously developed instrument that can be used to measure appearance and other patient-centred concerns.


The use of reliable, valid and responsive patient-reported outcome measures (PROMs) is essential to providing robust evidence about the impact and effectiveness of treatments for acne and acne scars. PROMs are questionnaires that measure how patients function and feel by asking them directly.[1] Both generic and acne-specific PROMs have been used in research to assess patient-reported outcomes such as health-related quality of life (HRQoL), mostly within the context of clinical trials.[2] Authors of a 2018 literature review of PROMs used in acne identified eight acne-specific measures:[3] the 21-item Acne Quality of Life Index;[4] the 19-item Acne-Specific Quality of Life Questionnaire;[5] the four-item Acne-Q4;[6] the 15-item Assessment of the Psychological and Social Effects of Acne;[7] the 10-item Acne Disability Index;[8] the five-item Cardiff Acne Disability Index;[9] the nine-item Acne Quality of Life;[10] and the 17-item Acne Symptom and Impact Scale.[11] Instruments not captured in the review include the 20-item Comprehensive Acne Quality of Life (CompAQ),[12] and two instruments for which only the concept elicitation findings were published: the 10-item facial acne scar quality of life (FasQoL) and the five-item self-assessment of clinical acne-related scars (SCARS).[13] Three of these 11 PROMs are specific to facial acne;[5,6,11] six are designed for acne in specific locations;[4,7–10,12] and two are scar-specific.[13] These PROMS have a total of 135 items of which 77·8% are in scales that measure psychosocial concerns (e.g. feeling embarrassed or self-conscious, or concern about going out and socializing due to acne); 14·1% measure physical symptoms (e.g. oily skin, scabs and pus); 2·9% measure treatment concerns (e.g. side-effects); and 5·2% measure appearance concerns (e.g. amount and visibility of acne or acne scars).

While acne-related psychosocial concepts are a crucially important outcome in acne care and research, and the primary focus of current acne-specific PROMs, an important outcome targeted by treatments – improvement in appearance – is largely overlooked by current PROMs. Few questionnaire items specifically ask patients to appraise how their skin and acne looks (e.g. up close, in photos or under a bright light). In clinical trials of treatments that aim to improve or clear acne, prevent and improve acne scarring, or prevent future outbreaks, a PROM that measures psychosocial issues alone would miss the opportunity to measure the more proximal outcome of skin or acne appearance.

Given the gaps in content in existing acne-specific PROMs, and the lack of PROMS for acne scarring, our team aimed to develop a new PROM – the ACNE-Q – to provide scales that measure appearance of facial skin, acne (face, chest and back) and acne scars, in addition to acne-specific symptoms and appearance-related distress.