title: Do repeated skin barrier measurements influence each other's results? An explorative study.
abstract: BACKGROUND
  Biophysical skin measurement techniques are widely used to quantify the skin barrier function. In clinical research usually several parameters are subsequently measured in the same skin areas. In this study, possible interfering effects of subsequent measurement procedures on transepidermal water loss (TEWL), stratum corneum hydration (SCH) and skin surface pH were investigated.
  
  
  METHODS
  An exploratory study was conducted. Twelve young (mean age 32.9 ± 7.2 years) and 12 elderly (mean age 68.3 ± 2.5 years) subjects without any skin diseases were enrolled. The parameters TEWL, skin surface pH, SCH, sebum content, and surface evaluation of living skin were obtained successively in pairs from 4 contralateral volar forearm skin areas.
  
  
  RESULTS
  SCH and skin surface pH seemed to be unaffected by previous measurement procedures. TEWL was systematically increased after pH and systematically decreased after stratum corneum measurements.
  
  
  CONCLUSIONS
  Measurements per se might interact with the skin, thus changing its characteristics. If several skin barrier function parameters need to be assessed subsequently in the same skin areas, we recommend that TEWL should be measured first followed by all others.
authors.affiliation: Department of Dermatology and Allergy, Clinical Research Center for Hair and Skin Science, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Kottner
authors.forename: Laine
authors.initials: L
authors.lastname: Ludriksone
authors.forename: Natalie
authors.initials: N
authors.lastname: Garcia Bartels
authors.forename: Ulrike
authors.initials: U
authors.lastname: Blume-Peytavi
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology; D019411:Clinical Laboratory Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D012629:Sebum / Q000378:metabolism; D012867:Skin / Q000378:metabolism; D012879:Skin Physiological Phenomena; D013499:Surface Properties; D014867:Water / Q000378:metabolism; D055815:Young Adult
chemical_list: D014867:Water