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Development and Validation of a Photonumeric Scale for Evaluation of Static Horizontal Forehead Lines
Alastair Carruthers1, Lisa Donofrio, Bhushan Hardas
1*Department of Dermatology and Skin Science, University of British Columbia, Vancouver, British Columbia, Canada; †Department of Dermatology, Yale University School of Medicine, New Haven, Connecticut; ‡Allergan plc, Irvine, California; §Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada; ‖UC Davis Medical Group, Sacramento, California; ¶Division of Dermatology, University of California at Los Angeles, Los Angeles, California; #Peloton Advantage, LLC, Parsippany, New Jersey.
The Allergan Forehead Lines Scale is a validated tool for objectively rating forehead lines. It demonstrates high reliability among physicians for assessing static forehead wrinkles.
Area of Science:
- Dermatology
- Aesthetic Medicine
- Cosmetic Science
Background:
- Objective and reproducible comparison of static forehead lines is crucial for treatment evaluation.
- Existing methods lack standardization for assessing forehead line severity.
- A validated scale is needed for clinical practice and research.
Purpose of the Study:
- To develop and validate the 5-point photonumeric Allergan Forehead Lines Scale.
- To establish a reliable tool for assessing static horizontal forehead lines.
- To provide a standardized method for treatment outcome assessment.
Main Methods:
- Development of the Allergan Forehead Lines Scale incorporating an assessment guide, verbal descriptors, morphed, and real subject images.
- Evaluation of clinical significance for a 1-point score difference using image pair reviews.
- Assessment of interrater and intrarater reliability through a live-subject validation study (N=295) across two sessions.
Main Results:
- A difference of 1 point or more on the scale signifies a clinically significant difference in forehead line severity.
- High intrarater agreement (mean weighted kappa = 0.87) and interrater agreement (0.86) were observed.
- The scale effectively differentiates between varying degrees of static forehead lines.
Conclusions:
- The Allergan Forehead Lines Scale is a validated and reliable instrument.
- It enables objective and reproducible physician ratings of static horizontal forehead lines.
- The scale can be utilized in clinical practice and research for consistent assessment.
