Children’s Perception Scale of Head Lice Infestation (CPS-HLI): Design and Psychometrics

Background: Pediculosis is a common ectoparasitic infestation that involves especially the skin of children worldwide. Studying the children’s perception of the disease’s risk factors, the effectiveness of personal preventive measures, and its implications for their health could be a major leap forward in health promotion activities. Objectives: This study aimed to develop and evaluate the psychometric properties of the Children’s Perception Scale of Head Lice Infestation (CPS-HLI) and its initial feasibility assessment for use on Iranian and possibly other elementary school children. Methods: The scale’s items were retained based on an extensive literature search and classified into the underlying constructs of the Extended Health Belief Model (EHBM). An expert panel endorsed the qualitative content and face validity of the preliminary draft, and 47 items remained for quantitative validity testing on a sample of 362 elementary school students in the city of Paveh, West of Iran. Explanatory and confirmatory factor analyses (EFA and CFA) were employed to test the content and structural validity of the constructed instrument. Cronbach's alpha and intra-class correlation coefficients were calculated to assess the internal consistency and reliability of the scale. Results: The values of Lawshe's content validity index (0.90) and content validity ratio (0.77), the subscales’ Cronbach's alpha (0.59), and intra-class correlation (0.72) coefficients confirmed plausible internal consistency of the scale. The values of root mean square error of approximation (RMSEA) (< 0.08 with χ2 < 0.05), Tucker-Lewis Index (TLI), and Comparative Fit Index (CFI) > 0.9 approved the applied statistical model’s goodness of fit. The ranges of Kaiser-Meyer-Olkin (KMO) measure of sampling adequacy for the underlying subscales (0.49 - 0.74) and the statistically significant result of Bartlett’s test of sphericity (P < 0.001) confirmed the patterned relationship among the constructed scale’s items. The principal component analysis that was performed using STATA favored the 11-factor solution. Conclusions: The study findings support the construct validity of CPS-HLI for use in studies on children’s perception of head lice infestation risk factors, the effectiveness of personal preventive measures, and the disease implications for their health and well-being. Further cross-cultural and cross-national validation studies are recommended for using the instrument in a wider range of populations and settings.