Baumann Skin Type Questionnaire (BSTQ): creation and validation of the Polish language version – part one

Introduction:
Baumann Skin Type Questionnaire (BSTQ) is a widely used questionnaire, that was designed to determine baseline skin type in dermatology. The self-reported BSTQ, consisting of four parts: oily vs. dry skin, sensitive vs. resistant skin, pigmented vs. non-pigmented skin and wrinkled vs. tight skin, can provide significant guidance for consumers and professionals to select and recommend the most appropriate skin care products and skin care protocols.

Aim:
Translation and validation of the Polish version of the Baumann Skin Type Questionnaire (BSTQ) – oily vs. dry skin and sensitive vs. resistant skin.

Material and methods:
Both forward and backward translation of the English version of the BSTQ was performed. The study was conducted on 103 individuals. The respondents completed the questionnaire twice, 1 day after the other. Moreover, the subjects participated in practical classes of facial care cosmetology which allowed for conducting interviews and skin examinations by a cosmetology expert.

Results:
The Polish version of the BSTQ demonstrated high test-retest reliability (reproducibility) in the dimension assessing oily or dry skin as well as sensitive or resistant skin (ICC3 = 0.91; ICC3 = 0.96, respectively) and good internal consistency, corroborated by Guttman’s Lambda 6 reliability (oily vs. dry: a_raw = 0.75, a_std = 0.74, G6 = 0.79; retest: a_raw = 0.77, a_std = 0.77, G6 = 0.81; sensitive vs. resistant: a_raw = 0.72, a_std = 0.74, G6 = 0.81; retest: a_raw = 0.78, a_std = 0.79, G6 = 0.85).

Conclusions:
The Polish version of the BSTQ (oily vs. dry skin and sensitive vs. resistant skin) showed high reliability, good internal consistency and high accuracy and consistency. It can be used for assessment of oily or dry skin and sensitive or resistant skin.