Carolyn H. Lund

Validity and Reliability of the Neonatal Skin Condition Score

OBJECTIVE To demonstrate the validity and reliability of the Neonatal Skin Condition Scale (NSCS) used in the Association of Womens Health, Obstetric and Neonatal Nurses (AWHONN) and the National Association of Neonatal Nurses (NANN) neonatal skin care evidence-based practice project. SETTING NICU and well-baby units in 27 hospitals located throughout the United States. PARTICIPANTS Site coordinators (N = 27) and neonates (N = 1,006) observed during both the pre and postimplementation phases of the original neonatal skin care project. METHOD To assess reliability, two consecutive NSCS assessments on a single infant were analyzed. Site coordinators were contacted after the original project was concluded. Sites indicating that a single nurse scored all infant skin observations provided data that were used to evaluate intrarater reliability. Sites using more than one nurse to score skin observations provided data that were used to assess interrater reliability. To assess validity, the following variables were used from the original data set: the Neonatal Skin Condition Scale (NSCS), with three subscales for dryness, erythema, and breakdown; birth weight in grams; number of skin score observations for each infant; and the prevalence of infection, defined as a positive blood culture. RESULTS For intrarater reliability, 16 sites used a single nurse for all NSCS assessments; total NSCS assessments 475. For interrater reliability, 11 sites used multiple raters; total assessments 531. The NSCS demonstrated adequate reliability for each of the three subscales and for the total score, with the percent agreement between scores ranging from 68.7% to 85.4% (intrarater) and 65.9% to 89% (interrater); all Kappas were significant at p < .001 and were in the moderate range for reliability. The validity of the NSCS was demonstrated by the findings that smaller infants were 6 times more likely to have erythema (chi2(6) = 109.55, p < .0001), and approximately twice as likely to have the most severe breakdown (chi2(6) = 108.01, p < .0001). Infants with more observations (longer length of stay) had higher skin scores (odds ratio = 1.21, p < .0001), and an increased probability of infection was noted for infants with higher skin scores (odds ratio = 2.25, p < .0001). CONCLUSIONS The Neonatal Skin Condition Score (NSCS) is reliable when used by single and multiple raters to assess neonatal skin condition, even across weight groups and racial groups. Validity of the NSCS was demonstrated by confirmation of the relationship of the skin condition scores with birth weight, number of observations, and prevalence of infection.

The development of skin barrier function in the neonate

The skin, one of the largest organs of the body, functions as a protective and regulatory barrier between the body and the external environment. At birth, infants must make the transition from a fluid intrauterine environment to dry, extrauterine life. Full-term infants, born at 40 weeks of gestation, make the transition with a competently formed barrier. However, the skin of the premature neonate comprises as much as 13% of the body weight, compared to only 3% of the body weight of an adult (1). In addition, the surface area to body weight ratio of the neonate is four times that of adults (2). Thus, the immaturity of the skin has numerous ramifications for the neonate, including ineffective thermoregulation (3), fluid imbalance (4), percutaneous absorption of toxins (2), tissue injury (5), infection (6), and delayed healing (7). Within the last decade, new technologies have changed the caretaking practices of the premature neonate; advances in respirator design, monitor technology, reduction of blood volume required for specialized tests, and the sophistication of new diagnostic techniques have all contributed to increasing the chances of survival of the premature neonate (8). Nevertheless, much remains to be learned about the complex extrauterine skin development of these neonates.