This prospective study aims to evaluate the responsiveness of the validated investigator global assessment (IGA) and composite area index score for keratosis pilaris by data collection through treatment and scoring sessions held at a private practice and relevant statistical analysis.

This is a prospective study aiming to evaluate the responsiveness of the IGA score for KP. KPAI is a 5-point IGA score (0-4) of five main body areas: face, upper limbs, lower limbs, trunk, and buttocks, for a maximum of 20 in two main categories, activity (erythema, skin roughness and papulation) and damage (pigmentation and scarring). The final score will be a maximum of 100. KPIGA, on the other hand, is a standard 0-4 IGA score. A Physician's Global Assessment Score and a 15-point Likert Scale would also be used by investigators, data collected act as external anchor for further responsiveness statistical analysis purpose.

4 scoring sessions will take place at Premier Specialists, Kogarah, Sydney with all co-investigators conducting the study in person at this single study site. Each dermatologist and medical professional involved will receive training on using the scores through a slideshow of training photos prior to the live scoring session. Firstly, a baseline score will be determined using the proposed scoring systems on the first scoring session. After that, participants will be offered 3 sessions of Nd: YAG laser 1064nm treatments at 4-week intervals on the affected skin of all body regions (face, upper limbs, lower limbs, trunk, and buttocks). The baseline KPIGA and KPAI scores obtained on the first scoring visit acts as the control for this pilot study and the scores obtained in the 3 progressive visits will be compared to the baseline. According to relevant study, the recommended Nd: YAG laser 1064nm treatment regimen is 3 treatment sessions at 4-week intervals. They will be scored before subsequent treatment sessions to see if there is any improvement in their KP and if the score is responsive to change.

Every participant will also complete the DLQI questionnaire during each visit. This data will be used to provide insight of patient's subjective perceptions of KP and the psychological impact it may have on them.

Inclusion Criteria:

1. All genders are allowed to participate
2. Age range: 18-80 years
3. Participants with Fitzpatrick skin type 1-3
4. Those with KP including subtypes of KP on the scored body regions (face, upper limbs, lower limbs, trunk, and buttocks)
5. Able to attend the scoring sessions
6. Participants having read and understood the PICF and are willing to participate
7. Of mature mind and able to provide informed consent
8. Able to maintain compliance with required study related procedures including completing the QOL questionnaire's

Exclusion Criteria:

1. Participants who are unwilling or unable to attend the scoring sessions
2. Those with other skin conditions overlapping the same area(s) as the KP
3. People younger than 18
4. People with darker skin i.e. Fitzpatrick skin type 4 or above
5. Those who had received any laser or dermabrasion therapy in the previous 6 months or topical treatment (keratolytic agents or corticosteroids) in the previous 1 month before the study treatment session
6. Those with a history of keloid or hypertrophic scars
7. Those being on photosensitive medications, allergic to intervention agents
8. Pregnant or lactating

All data obtained will be stored securely on-site premises and will not be articulated outside of Australia. Data obtained from patients through scoring sheets and QOL questionnaires will be transcribed as de-identifiable data in an Excel spreadsheet into a password-protected computer (only the investigators with the corresponding study codes given to each patient can identify the data for the purpose of study data analysis). The original scoring sheets and QOL questionnaires will be stored securely on-site and may only be accessed by investigators and co-investigators, as detailed in the patient consent form.