Mapping of Indonesians' Skin Type Based on Baumann Skin Type Indicator-Indonesia and Development of Artificial Intelligence Modelling

The goal of this observational study is to learn about the skin type of Indonesians based on Baumann Skin Type Indicator Questionnaire in Indonesian language version, and to develop artificial intelligence modelling of BSTI-Ina. The main questions it aims to answer are:

1. What is the measurement of the validity and reliability of BSTI-Ina questionnaire year 2006 version which was adapted from BSTI questionnaire in English language year 2006 version as a specific measurement to identify skin type?
2. What is the measurement of the validity and reliability of BSTI-Ina questionnaire year 2022 version which was adapted from BSTI questionnaire in English language year 2022 version as a specific measurement to identify skin type?
3. What is the comparison of the validity and reliability between BSTI-Ina questionnaire year 2006 and year 2022 to determine Indonesian adult population's skin type?
4. How is the mapping of Indonesians' skin type based on BSTI-Ina?
5. What is the proportion of each skin type based on BSTI-Ina in Indonesian population?
6. What is the proportion of each skin type based on BSTI-Ina in Indonesian population sociodemographically?
7. How can Artificial Intelligence help categorize skin type based on BSTI-Ina automatically?

Participants are males and females between 18-59 year old. Participants will be asked to fill BSTI-Ina questionnaire. Participants then will be photographed in five different positions.

This research is an observational study with a cross-sectional design. The aims of this study is to determine the validity and reliability of BSTI questionnaire translated in Indonesian and to develop artificial intelligence modelling for BSTI-Ina based on photographs. This study will be held in 13 research centers with a total of 1950 subjects consists of males and females age 18-59. It conducts of 2 phases. Phase 1 is to determine which version of BSTI will be used based on which one is more valid and reliable being translated in Indonesian and will be conducted in Jakarta as a pilot. In phase 1, participants will be asked to fill both BSTI-Ina 2006 and 2002 questionnaire. Participants then will be photographed in five different positions. Data will be analyzed to determine which of BSTI-Ina version is more valid and reliable. After deciding which BSTI-Ina version will be used, the study then goes to phase 2. Phase 2 will be conducted in 12 other research centers in Indonesia to map Indonesian population skin type. In both 2 phases, all participants will be asked to fill in BSTI-Ina questionnaire (either 2006 or 2022 version based on the result of Phase 1). Participants then will be photographed in five different positions. After all the data from all research centers are collected, data will be analyzed to map Indonesian population's skin type. Data as participants' skin types and photographs will also be processed by machine to model artificial intelligence. The aim is to automatically categorize skin type based on BSTI-Ina based on photographs.

Eligibility Criteria:
Inclusion Criteria:

* Males and females age 18-59 year old.
* Fitzpatrick's skin type III-V
* Educational degree of minimum high school
* Can speak Indonesian
* Can read
* Willing to participate and sign informed consent

Exclusion Criteria:

* Participant who doesn't fill the questionnaire completely
* Participant with skin disease involving \>25% facial area